0001564590-21-053722 | 10-Q | XBRL Viewer

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Amount

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Document and Entity Information - shares	9 Months Ended
Document and Entity Information - shares	Sep. 30, 2021	Oct. 27, 2021
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2021
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q3
Trading Symbol	PSN
Entity Registrant Name	Parsons Corporation
Entity Central Index Key	0000275880
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Shell Company	false
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Common Stock, Shares Outstanding		102,257,780
Entity File Number	001-07782
Entity Tax Identification Number	95-3232481
Entity Address, Address Line One	5875 Trinity Parkway #300
Entity Address, City or Town	Centreville
Entity Address, State or Province	VA
Entity Address, Postal Zip Code	20120
City Area Code	703
Local Phone Number	988-8500
Title of 12(b) Security	Common Stock, $1 par value
Security Exchange Name	NYSE
Document Quarterly Report	true
Document Transition Report	false
Entity Incorporation, State or Country Code	DE
Entity Interactive Data Current	Yes

Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents (including $51,516 and $75,220 Cash of consolidated joint ventures)	$ 275,506	$ 483,609
Restricted cash and investments	1,197	3,606
Accounts receivable, net (including $152,471 and $190,643 Accounts receivable of consolidated joint ventures, net)	627,445	698,578
Contract assets (including $27,354 and $23,498 Contract assets of consolidated joint ventures)	569,294	576,568
Prepaid expenses and other current assets (including $21,764 and $3,045 Prepaid expenses and other current assets of consolidated joint ventures)	113,129	80,769
Total current assets	1,586,571	1,843,130
Property and equipment, net (including $1,499 and $2,629 Property and equipment of consolidated joint ventures, net)	105,895	121,027
Right of use assets, operating leases	188,519	210,398
Goodwill	1,411,465	1,261,978
Investments in and advances to unconsolidated joint ventures	102,677	68,975
Intangible assets, net	235,927	245,958
Deferred tax assets	147,260	130,200
Other noncurrent assets	45,619	56,038
Total assets	3,823,933	3,937,704
Current liabilities:
Accounts payable (including $93,697 and $97,810 Accounts payable of consolidated joint ventures)	188,761	225,679
Accrued expenses and other current liabilities (including $81,336 and $68,801 Accrued expenses and other current liabilities of consolidated joint ventures)	626,171	650,753
Contract liabilities (including $18,720 and $33,922 Contract liabilities of consolidated joint ventures)	186,789	201,864
Short-term lease liabilities, operating leases	54,466	54,133
Income taxes payable	4,472	4,980
Short-term debt	0	50,000
Total current liabilities	1,060,659	1,187,409
Long-term employee incentives	19,486	21,828
Long-term debt	591,399	539,998
Long-term lease liabilities, operating leases	157,590	182,467
Deferred tax liabilities	23,554	12,285
Other long-term liabilities	117,369	132,300
Total liabilities	1,970,057	2,076,287
Contingencies (Note 12)
Shareholders' equity:
Common stock, $1 par value; authorized 1,000,000,000 shares; 146,506,406 and 146,609,288 shares issued; 32,538,566 and 25,719,350 public shares outstanding; 69,719,214 and 76,641,312 ESOP shares outstanding	146,507	146,609
Treasury stock, 44,248,626 shares at cost	(899,328)	(899,328)
Additional paid-in capital	2,669,692	2,700,925
Accumulated deficit	(82,661)	(120,569)
Accumulated other comprehensive loss	(10,132)	(13,865)
Total Parsons Corporation shareholders' equity	1,824,078	1,813,772
Noncontrolling interests	29,798	47,645
Total shareholders' equity	1,853,876	1,861,417
Total liabilities and shareholders' equity	$ 3,823,933	$ 3,937,704

Consolidated Balance Sheets (Parenthetical) (Unaudited) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Cash and cash equivalents	$ 275,506	$ 483,609
Accounts receivable, net	627,445	698,578
Contract assets	569,294	576,568
Prepaid expenses and other current assets	113,129	80,769
Property and equipment, net	105,895	121,027
Accounts payable	188,761	225,679
Accrued expenses and other current liabilities	626,171	650,753
Contract liabilities	$ 186,789	$ 201,864
Common stock, par value	$ 1	$ 1
Common stock, shares authorized	1,000,000,000	1,000,000,000
Common stock, shares, issued	146,506,406	146,609,288
Common stock, shares, outstanding	32,538,566	25,719,350
Treasury stock, shares	44,248,626	44,248,626
ESOP
Common stock, shares, outstanding	69,719,214	76,641,312
Consolidated Joint Ventures
Cash and cash equivalents	$ 51,516	$ 75,220
Accounts receivable, net	152,471	190,643
Contract assets	27,354	23,498
Prepaid expenses and other current assets	21,764	3,045
Property and equipment, net	1,499	2,629
Accounts payable	93,697	97,810
Accrued expenses and other current liabilities	81,336	68,801
Contract liabilities	$ 18,720	$ 33,922

Consolidated Statements of Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Income Statement [Abstract]
Revenue	$ 956,050	$ 1,004,236	$ 2,710,103	$ 2,954,688
Direct cost of contracts	734,652	788,769	2,084,062	2,307,725
Equity in earnings of unconsolidated joint ventures	9,570	16,741	26,528	26,624
Selling, general and administrative expenses	191,231	165,937	566,991	537,351
Operating income	39,737	66,271	85,578	136,236
Interest income	65	88	315	512
Interest expense	(4,052)	(5,475)	(13,503)	(13,656)
Other income (expense), net	184	1,653	(1,202)	1,916
Total other income (expense)	(3,803)	(3,734)	(14,390)	(11,228)
Income before income tax expense	35,934	62,537	71,188	125,008
Income tax expense	(9,165)	(16,017)	(18,378)	(32,992)
Net income including noncontrolling interests	26,769	46,520	52,810	92,016
Net income attributable to noncontrolling interests	(7,411)	(5,862)	(17,711)	(15,086)
Net income attributable to Parsons Corporation	$ 19,358	$ 40,658	$ 35,099	$ 76,930
Earnings per share:
Basic	$ 0.19	$ 0.40	$ 0.34	$ 0.76
Diluted	$ 0.18	$ 0.40	$ 0.33	$ 0.76

Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Statement Of Income And Comprehensive Income [Abstract]
Net income including noncontrolling interests	$ 26,769	$ 46,520	$ 52,810	$ 92,016
Other comprehensive income (loss), net of tax
Foreign currency translation adjustment, net of tax	(4,205)	1,926	3,721	(3,770)
Pension adjustments, net of tax	(26)	20	12	(18)
Comprehensive income including noncontrolling interests, net of tax	22,538	48,466	56,543	88,228
Comprehensive income attributable to noncontrolling interests, net of tax	(7,407)	(5,866)	(17,711)	(15,086)
Comprehensive income attributable to Parsons Corporation, net of tax	$ 15,131	$ 42,600	$ 38,832	$ 73,142

- Definition

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income (loss) and other comprehensive income (loss), attributable to noncontrolling interests. Excludes changes in equity resulting from investments by owners and distributions to owners.

+ References + Details

- Definition

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income. Excludes changes in equity resulting from investments by owners and distributions to owners.

+ References + Details

- Definition

The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

+ References

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+ Details

Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Cash flows from operating activities:
Net income including noncontrolling interests	$ 52,810	$ 92,016
Adjustments to reconcile net income to net cash provided by operating activities
Depreciation and amortization	106,540	95,442
Amortization of debt issue costs	2,173	760
Amortization of convertible notes discount	0	1,277
Loss (gain) on disposal of property and equipment	357	(22)
Provision for doubtful accounts	8	54
Deferred taxes	(4,369)	(763)
Foreign currency transaction gains and losses	3,107	431
Equity in earnings of unconsolidated joint ventures	(26,528)	(26,624)
Return on investments in unconsolidated joint ventures	20,547	31,189
Stock-based compensation	15,544	11,044
Contributions of treasury stock	41,312	42,006
Changes in assets and liabilities, net of acquisitions and newly consolidated joint ventures:
Accounts receivable	70,355	(106,487)
Contract assets	13,262	(34,931)
Prepaid expenses and other assets	(19,596)	7,649
Accounts payable	(39,341)	(8,074)
Accrued expenses and other current liabilities	(86,402)	48,901
Contract liabilities	(16,294)	(18,094)
Income taxes	(498)	(6,761)
Other long-term liabilities	(17,273)	(15,574)
Net cash provided by operating activities	115,714	113,439
Cash flows from investing activities:
Capital expenditures	(12,803)	(29,178)
Proceeds from sale of property and equipment	1,049	1,053
Payments for acquisitions, net of cash acquired	(197,672)	0
Investments in unconsolidated joint ventures	(36,102)	(7,969)
Return of investments in unconsolidated joint ventures	729	17
Proceeds from sales of investments in unconsolidated joint ventures	14,335	0
Net cash used in investing activities	(230,464)	(36,077)
Cash flows from financing activities:
Proceeds from borrowings under credit agreement	0	212,900
Repayments of borrowings under credit agreement	(50,000)	(212,900)
Payments for debt costs and credit agreement	(1,937)	0
Proceeds from issuance of convertible notes	0	400,000
Payments for purchase of bond hedges	0	(54,968)
Proceeds from issuance of warrants	0	13,808
Transaction costs paid in connection with convertible notes issuance	0	(10,307)
Contributions by noncontrolling interests	1,688	491
Distributions to noncontrolling interests	(37,246)	(4,469)
Repurchases of common stock	(8,701)	0
Taxes paid on vested stock	(2,242)	(1,149)
Proceeds from issuance of common stock	2,773	1,684
Net cash (used in) provided by financing activities	(95,665)	345,090
Effect of exchange rate changes	(97)	(69)
Net decrease in cash, cash equivalents, and restricted cash	(210,512)	422,383
Cash, cash equivalents and restricted cash:
Beginning of year	487,215	195,374
End of period	$ 276,703	$ 617,757

Consolidated Statements of Shareholder's Equity (Unaudited) - USD ($) $ in Thousands	Total	Revision of Prior Period, Accounting Standards Update, Adjustment	Common Stock	Treasury Stock	Additional Paid-in Capital	Additional Paid-in Capital Revision of Prior Period, Accounting Standards Update, Adjustment	Retained Earnings (Accumulated Deficit)	Retained Earnings (Accumulated Deficit) Revision of Prior Period, Accounting Standards Update, Adjustment	Accumulated Other Comprehensive Income (Loss)	Total Parsons Equity	Total Parsons Equity Revision of Prior Period, Accounting Standards Update, Adjustment	Noncontrolling Interest
Beginning balance at Dec. 31, 2019	$ 1,660,756		$ 146,441	$ (934,240)	$ 2,649,975		$ (218,025)		$ (14,261)	$ 1,629,890		$ 30,866
Beginning balance (ASU 2016-13) at Dec. 31, 2019		$ (1,000)						$ (1,000)			$ (1,000)
Comprehensive income
Net income	92,016						76,930			76,930		15,086
Foreign currency translation gain (loss), net	(3,770)								(3,770)	(3,770)
Pension adjustments, net	(18)								(18)	(18)
Contributions	491											491
Distributions	(4,469)											(4,469)
Issuance of equity securities, net of retirements	1,672		57		1,615					1,672
Equity component value of convertible note issuance	53,552				53,552					53,552
Purchase of convertible note hedge	(54,611)				(54,611)					(54,611)
Sale of common stock warrants	13,808				13,808					13,808
Stock-based compensation	11,044				11,044					11,044
Ending Balance at Sep. 30, 2020	1,769,471		146,498	(934,240)	2,675,383		(142,095)		(18,049)	1,727,497		41,974
Beginning balance at Jun. 30, 2020	1,706,252		146,496	(934,240)	2,658,036		(182,753)		(19,991)	1,667,548		38,704
Comprehensive income
Net income	46,520						40,658			40,658		5,862
Foreign currency translation gain (loss), net	1,926								1,922	1,922		4
Pension adjustments, net	20								20	20
Contributions	268											268
Distributions	(2,864)											(2,864)
Issuance of equity securities, net of retirements	(12)		2		(14)					(12)
Equity component value of convertible note issuance	53,552				53,552					53,552
Purchase of convertible note hedge	(54,611)				(54,611)					(54,611)
Sale of common stock warrants	13,808				13,808					13,808
Stock-based compensation	4,612				4,612					4,612
Ending Balance at Sep. 30, 2020	1,769,471		146,498	(934,240)	2,675,383		(142,095)		(18,049)	1,727,497		41,974
Beginning balance at Dec. 31, 2020	1,861,417		146,609	(899,328)	2,700,925		(120,569)		(13,865)	1,813,772		47,645
Beginning balance (ASU 2020-06) at Dec. 31, 2020		$ (37,220)				$ (40,002)		$ 2,782			$ (37,220)
Comprehensive income
Net income	52,810						35,099			35,099		17,711
Foreign currency translation gain (loss), net	3,721								3,721	3,721
Pension adjustments, net	12								12	12
Contributions	1,688											1,688
Distributions	(37,246)											(37,246)
Issuance of equity securities, net of retirements	1,851		143		1,681		27			1,851
Repurchases of common stock	(8,701)		(245)		(8,456)					(8,701)
Stock-based compensation	15,544				15,544					15,544
Ending Balance at Sep. 30, 2021	1,853,876		146,507	(899,328)	2,669,692		(82,661)		(10,132)	1,824,078		29,798
Beginning balance at Jun. 30, 2021	1,850,450		146,752	(899,328)	2,673,965		(102,019)		(5,905)	1,813,465		36,985
Comprehensive income
Net income	26,769						19,358			19,358		7,411
Foreign currency translation gain (loss), net	(4,205)								(4,201)	(4,201)		(4)
Pension adjustments, net	(26)								(26)	(26)
Contributions	816											816
Distributions	(15,410)											(15,410)
Repurchases of common stock	(8,701)		(245)		(8,456)					(8,701)
Stock-based compensation	4,183				4,183					4,183
Ending Balance at Sep. 30, 2021	$ 1,853,876		$ 146,507	$ (899,328)	$ 2,669,692		$ (82,661)		$ (10,132)	$ 1,824,078		$ 29,798

Description of Operations

9 Months Ended

Sep. 30, 2021

Description Of Operations Disclosure [Abstract]

Description of Operations

1.	Description of Operations

Organization

Parsons Corporation, a Delaware corporation, and its subsidiaries (collectively, the “Company”) is a leading provider of technology-driven solutions in the defense, intelligence and critical infrastructure markets. We provide software and hardware products, technical services and integrated solutions to support our customers’ missions. We have developed significant expertise and differentiated capabilities in key areas of cybersecurity, intelligence, missile defense, C5ISR, space, geospatial, and connected communities. By combining our talented team of professionals and advanced technology, we help solve complex technical challenges to enable a safer, smarter and more interconnected world.

Basis of Presentation and Principles of Consolidation

9 Months Ended

Sep. 30, 2021

Organization Consolidation And Presentation Of Financial Statements [Abstract]

Basis of Presentation and Principles of Consolidation

2.	Basis of Presentation and Principles of Consolidation

The accompanying unaudited consolidated financial statements and related notes of the Company have been prepared in accordance with generally accepted accounting principles in the United States of America ("GAAP") and pursuant to the interim period reporting requirements of Form 10-Q. They do not include all of the information and footnotes required by GAAP for complete financial statements and, therefore, should be read in conjunction with our consolidated financial statements and the notes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2020.

In the opinion of management, the consolidated financial statements reflect all normal recurring adjustments necessary for a fair statement of the financial position, results of operations and cash flows for the interim periods presented. The results of operations and cash flows for any interim period are not necessarily indicative of results for the full year or for future years.

This Quarterly Report on Form 10-Q includes the accounts of Parsons Corporation and its subsidiaries and affiliates which it controls. Interests in joint ventures that are controlled by the Company, or for which the Company is otherwise deemed to be the primary beneficiary, are consolidated. For joint ventures in which the Company does not have a controlling interest, but exerts a significant influence, the Company applies the equity method of accounting (see “Note 14 – Investments in and Advances to Joint Ventures" for further discussion). Intercompany accounts and transactions are eliminated in consolidation.

Use of Estimates

The preparation of the consolidated financial statements in accordance with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual amounts could differ from those estimates. The Company’s most significant estimates and judgments involve revenue recognition with respect to the determination of the costs to complete contracts and transaction price; determination of self-insurance reserves; useful lives of property and equipment and intangible assets; calculation of allowance for doubtful accounts; valuation of deferred income tax assets and uncertain tax positions, among others. Please see “Management’s Discussion and Analysis of Financial Condition and Results of Operations—Critical Accounting Policies and Estimates” and “Note 2—Summary of Significant Accounting Polices” in the notes to our consolidated financial statements included in the Company’s Form 10-K for the year ended December 31, 2020, for a discussion of the significant estimates and assumptions affecting our consolidated financial statements. Estimates of costs to complete contracts are continually evaluated as work progresses and are revised when necessary. When a change in estimate is determined to have an impact on contract profit, the Company records a positive or negative adjustment to the consolidated statement of income.

Employee Stock Purchase Plan

During the second quarter of fiscal 2020, initial purchases of the Company’s common Stock were made under the Parsons Employee Stock Purchase Program (“ESPP”). Under the ESPP, eligible employees who elect to participate are granted the right to purchase shares of the common stock of Parsons at a discount that is limited to 5% of the per-share market value on the day shares are sold to employees. Purchases of common stock under the ESPP are included in

“proceeds from issuance of common stock” in cash flows from financing activities in the Consolidated Statements of Cash Flows.

Stock Repurchase Plan

During the third quarter of 2021, the Company’s Board of Directors authorized the Company to acquire a number of shares of Common Stock having an aggregate market value of not greater than $100,000,000 from time to time. Repurchased shares of common stock are retired and included in “Repurchases of common stock” in cash flows from financing activities in the Consolidated Statements of Cash Flows.

New Accounting Pronouncements

9 Months Ended

Sep. 30, 2021

Accounting Policies [Abstract]

New Accounting Pronouncements

3.	New Accounting Pronouncements

In the first quarter of 2021, the Company early adopted Accounting Standards Update (“ASU”) ASU 2020-06, Debt – Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging – Contracts in Entity’s Own Equity (Subtopic 815-40) (“ASU 2020-06)”. The update simplifies the accounting for convertible debt instruments and convertible preferred stock by reducing the number of accounting models and limiting the number of embedded conversion features separately recognized from the primary contract. The guidance also includes targeted improvements to the disclosures for convertible instruments and earnings per share. ASU 2020-06 is effective for fiscal years beginning after December 15, 2021, including interim periods within those fiscal years. Early adoption is permitted, but no earlier than fiscal years beginning after December 15, 2020. The Company adopted ASU 2020-06 in the first quarter of 2021 using the modified retrospective method which resulted in a reduction in non-cash interest expense and reclassification of the equity portion of the Convertible Senior Notes to “Long-term debt” on the consolidated balance sheet.

In the first quarter of 2021, the Company adopted ASU No. 2019-12, “Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes (“ASU 2019-12”)”. ASU 2019-12 was issued as a means to reduce the complexity of accounting for income taxes. The guidance is to be applied using a prospective method, excluding amendments related to franchise taxes, which should be applied on either a retrospective basis for all periods presented or a modified retrospective basis through a cumulative-effect adjustment to retained earnings as of the beginning of the fiscal year of adoption. The adoption of ASU 2019-12 did not have a material impact on the consolidated financial statements.

In the first quarter of 2020, the Company adopted ASU 2016-13, “Measurement of Credit Losses on Financial Instruments.” The amendments in ASU 2016-13 replaced the incurred loss impairment methodology in current practice with a methodology that reflects expected credit losses and requires consideration of a broader range of reasonable and supportable information to estimate credit losses. The adoption of ASU 2016-13 did not have a material impact on the consolidated financial statements.

- Definition

The entire disclosure for change in accounting principle. Includes, but is not limited to, nature, reason, and method of adopting amendment to accounting standards or other change in accounting principle.

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+ Details

Acquisitions

9 Months Ended

Sep. 30, 2021

Business Combinations [Abstract]

Acquisitions

4.	Acquisitions

BlackHorse Solutions, Inc.

On July 6, 2021, the Company acquired a 100% ownership interest in BlackHorse Solutions, Inc (“BlackHorse”), a privately-owned company, for $205.0 million in cash. BlackHorse expands Parsons’ capabilities and products in next-generation military, intelligence, and space operations, specifically in cyber electronic warfare and information dominance. The acquisition was entirely funded by cash on-hand. In connection with this acquisition, the Company recognized $3.0 million of acquisition related “Selling, general and administrative expense” in the consolidated statements of income for the three months ended September 30, 2021, including legal fees, consulting fees, and other miscellaneous direct expenses associated with the acquisition.

The following table summarizes the estimated fair values of the assets acquired and liabilities assumed based on the purchase price allocation as of the date of acquisition (in thousands):

	Amount
Cash and cash equivalents	$	15,428
Accounts receivable		3,351
Contract assets		5,979
Prepaid expenses and other current assets		977
Property and equipment		2,278
Right of use assets, operating leases		6,157
Goodwill		142,948
Intangible assets		65,000
Accounts payable		(2,326	)
Accrued expenses and other current liabilities		(17,197	)
Contract liabilities		(320	)
Short-term lease liabilities, operating leases		(1,011	)
Long-term lease liabilities, operating leases		(5,146	)
Deferred tax liabilities		(11,091	)
Net assets acquired	$	205,027

Of the total purchase price, the following values were assigned to intangible assets (in thousands, except for years):

	Gross Carrying Amount		Amortization Period
			(in years)
Customer relationships	$	40,000	16
Backlog		22,000	3
Trade name		1,000	2
Developed technologies		1,000	3
Non-compete agreements		1,000	3

Amortization expense of $2.6 million related to these intangible assets was recorded for the three months ended September 30, 2021. The entire value of goodwill was assigned to the Federal Solutions reporting unit and represents synergies expected to be realized from this business combination. Goodwill of $10.6 million is deductible for tax purposes.

The amount of revenue generated by BlackHorse and included within consolidated revenues is $16.7 million for the three months ended September 30, 2021. The Company has determined that the presentation of net income from the date of acquisition is impracticable due to the integration of general corporate functions upon acquisition.

The Company is still in the process of finalizing its valuation of the net assets acquired.

Supplemental Pro Forma Information (Unaudited)

Supplemental information of unaudited pro forma operating results assuming the BlackHorse acquisition had been consummated as of the beginning of fiscal year 2020 (in thousands) is as follows:

	Three Months Ended				Nine Months Ended
	September 30, 2021		September 30, 2020		September 30, 2021		September 30, 2020
Pro forma Revenue	$	957,498	$	1,017,325	$	2,748,559	$	2,988,153
Pro forma Net Income including noncontrolling interests		31,070		45,195	$	56,694	$	82,921

Echo Ridge LLC

On July 30, 2021, the Company acquired a 100% ownership interest in Echo Ridge LLC (“Echo Ridge”), a privately-owned company, for $9.0 million in cash. Echo Ridge adds position, navigation, and timing devices; modeling, simulation, test, and measurement tools; and deployable software defined radio products and signal processing services to Parsons’ space portfolio. The acquisition was entirely funded by cash on-hand. In connection with this acquisition, the Company recognized $0.3 million of acquisition related “Selling, general and administrative expense” in the consolidated statements of income for the three months ended September 30, 2021, including legal fees, consulting fees, and other miscellaneous direct expenses associated with the acquisition. The Company allocated the purchase price to the appropriate classes of tangible assets and liabilities and assigned the excess of $7.2 million to goodwill. The entire value of goodwill was assigned to the Federal Solutions reporting unit and represents synergies expected to be realized from this business combination. Goodwill in its entirety is deductible for tax purposes.

Braxton Science & Technology Group

On November 19, 2020, the Company acquired a 100% ownership interest in Braxton Science & Technology Group (“Braxton”), a privately-owned company, for $309.5 million in cash. Braxton operates at the forefront of satellite operations, ground system automation, flight dynamics, and spacecraft and antenna simulation for the U.S. Department of Defense and Intelligence Community. The acquisition was entirely funded by cash on hand. In connection with this acquisition, the Company recognized $0.6 million of acquisition related “Selling, general and administrative expense” in the consolidated statements of income for the nine months ended September 30, 2021, including legal fees, consulting fees, and other miscellaneous direct expenses associated with the acquisition. Braxton allows Parsons to capitalize on the quickly evolving space missions of its national security space customers and address rapid market growth driven by proliferated low earth orbit constellations, small satellite expansion, and space cyber resiliency.

The following table summarizes the estimated fair values of the assets acquired and liabilities assumed based on the purchase price allocation as of the date of acquisition (in thousands):

	Amount
Cash and cash equivalents	$	7,006
Accounts receivable		18,163
Contract assets		8,350
Prepaid expenses and other current assets		3,036
Property and equipment		5,114
Right of use assets, operating leases		10,788
Goodwill		212,185
Intangible assets		74,950
Accounts payable		(7,464	)
Accrued expenses and other current liabilities		(9,845	)
Contract liabilities		(300	)
Short-term lease liabilities, operating leases		(1,915	)
Long-term lease liabilities, operating leases		(8,873	)
Deferred tax liabilities		(1,694	)
Net assets acquired	$	309,501

Of the total purchase price, the following values were assigned to intangible assets (in thousands, except for years):

Amortization expense of $4.0 million and $12.1 million related to these intangible assets was recorded for the three and nine months ended September 30, 2021, respectively. The entire value of goodwill was assigned to the Federal Solutions reporting unit and represents synergies expected to be realized from this business combination. Goodwill of $196.3 million is deductible for tax purposes.

The amount of revenue generated by Braxton and included within consolidated revenues is $34.0 million and $94.3 million for the three and nine months ended September 30, 2021, respectively. The Company has determined that the presentation of net income from the date of acquisition is impracticable due to the integration of general corporate functions upon acquisition.

Supplemental Pro Forma Information (Unaudited)

Supplemental information of unaudited pro forma operating results assuming the Braxton acquisition had been consummated as of the beginning of fiscal year 2019 (in thousands) is as follows:

	Three Months Ended				Nine Months Ended
	September 30, 2021		September 30, 2020		September 30, 2021		September 30, 2020
Pro forma Revenue	$	956,050	$	1,046,002	$	2,710,103	$	3,050,708
Pro forma Net Income including noncontrolling interests		27,463		48,072	$	55,391	$	93,672

Contracts with Customers

9 Months Ended

Sep. 30, 2021

Revenue From Contract With Customer [Abstract]

Contracts with Customers

5.	Contracts with Customers

Disaggregation of Revenue

The Company’s contracts contain both fixed-price and cost reimbursable components. Contract types are based on the component that represents the majority of the contract. The following table presents revenue disaggregated by contract type (in thousands):

	Three Months Ended				Nine Months Ended
	September 30, 2021		September 30, 2020		September 30, 2021		September 30, 2020
Fixed-Price	$	246,894	$	324,901	$	710,067	$	944,577
Time-and-Materials		261,566		265,987		754,596		777,807
Cost-Plus		447,590		413,348		1,245,440		1,232,304
Total	$	956,050	$	1,004,236	$	2,710,103	$	2,954,688

See “Note 18 – Segments Information” for the Company’s revenues by business lines.

Contract Assets and Contract Liabilities

Contract assets and contract liabilities balances at September 30, 2021 and December 31, 2020 were as follows (in thousands):

	September 30, 2021		December 31, 2020		$ change			% change
Contract assets	$	569,294	$	576,568	$	(7,274	)		-1.3	%
Contract liabilities		186,789		201,864		(15,075	)		-7.5	%
Net contract assets (liabilities) (1)	$	382,505	$	374,704	$	7,801			2.1	%

(1)

Total contract retentions included in net contract assets (liabilities) were $94.3 million as of September 30, 2021, of which $52.3 million are not expected to be paid in the next 12 months. Total contract retentions included in net contract assets (liabilities) were $93.8 million as of December 31, 2020. Contract assets at September 30, 2021 and December 31, 2020 include $106.0 million and $116.6 million, respectively, related to unapproved change orders, claims, and requests for equitable adjustment. For the three and nine months ended September 30, 2021 and September 30, 2020, there were no material losses recognized related to the collectability of claims, unapproved change orders, and requests for equitable adjustment.

During the three months ended September 30, 2021 and September 30, 2020, the Company recognized revenue of $3.0 million and $9.5 million, respectively, and $95.5 million and $132.2 million during the nine months ended September 30, 2021 and September 30, 2020, respectively, that was included in the corresponding contract liability balances at December 31, 2020 and December 31, 2019, respectively. Certain changes in contract assets and contract liabilities consisted of the following:

	September 30, 2021		December 31, 2020
Acquired contract assets	$	5,979	$	8,350
Acquired contract liabilities		320		300

There was no significant impairment of contract assets recognized during the three and nine months ended September 30, 2021 and September 30, 2020.

Revisions in estimates, such as changes in estimated claims or incentives, related to performance obligations partially satisfied in previous periods that individually had an impact of $5 million or more on revenue resulted in the following changes in revenue:

	Three Months Ended						Nine Months Ended
	September 30, 2021			September 30, 2020			September 30, 2021			September 30, 2020
Revenue impact, net	$	(6,300	)	$	(134	)	$	(27,553	)	$	8,848

Accounts Receivable, net

Accounts receivable, net consisted of the following as of September 30, 2021 and December 31, 2020 (in thousands):

	2021			2020
Billed	$	443,024		$	512,357
Unbilled		188,428			190,222
Total accounts receivable, gross		631,452			702,579
Allowance for doubtful accounts		(4,007	)		(4,001	)
Total accounts receivable, net	$	627,445		$	698,578

Billed accounts receivable represents amounts billed to clients that have not been collected. Unbilled accounts receivable represents amounts where the Company has a present contractual right to bill but an invoice has not been issued to the customer at the period-end date.

The allowance for doubtful accounts was determined based on consideration of trends in actual and forecasted credit quality of clients, including delinquency and payment history, type of client, such as a government agency or commercial sector client, and general economic conditions and particular industry conditions that may affect a client’s ability to pay. We have not seen and do not expect there to be a risk of non-payment from either our government agency or commercial customers related to COVID-19 impacts; however, we have experienced payment delays due to administrative limitations from both types of customers.

Transaction Price Allocated to the Remaining Unsatisfied Performance Obligations

The Company’s remaining unsatisfied performance obligations (“RUPO”) as of September 30, 2021 represent a measure of the total dollar value of work to be performed on contracts awarded and in-progress. The Company had $6.0 billion in RUPO as of September 30, 2021.

RUPO will increase with awards of new contracts and decrease as the Company performs work and recognizes revenue on existing contracts. Projects are included within RUPO at such time the project is awarded and agreement on contract terms has been reached. The difference between RUPO and backlog relates to unexercised option years that are included within backlog and the value of Indefinite Delivery/Indefinite Quantity (“IDIQ”) contracts included in backlog for which delivery orders have not been issued.

RUPO is comprised of: (a) original transaction price, (b) change orders for which written confirmations from our customers have been received, (c) pending change orders for which the Company expects to receive confirmations in the ordinary course of business, and (d) claim amounts that the Company has made against customers for which it has determined that it has a legal basis under existing contractual arrangements and a significant reversal of revenue is not probable, less revenue recognized to-date.

The Company expects to satisfy its RUPO as of September 30, 2021 over the following periods (in thousands):

Period RUPO Will Be Satisfied	Within One Year		Within One to Two Years		Thereafter
Federal Solutions	$	1,418,783	$	787,273	$	491,797
Critical Infrastructure		1,452,760		781,669		1,021,928
Total	$	2,871,543	$	1,568,942	$	1,513,725

- Definition

The entire disclosure of revenue from contract with customer to transfer good or service and to transfer nonfinancial asset. Includes, but is not limited to, disaggregation of revenue, credit loss recognized from contract with customer, judgment and change in judgment related to contract with customer, and asset recognized from cost incurred to obtain or fulfill contract with customer. Excludes insurance and lease contracts.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-URI http://asc.fasb.org/topic&trid=49130388

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=123351226&loc=SL49130551-203045

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=123351226&loc=SL49130556-203045

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123351226&loc=SL49130554-203045

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
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-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=123351226&loc=SL49130554-203045

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123351226&loc=SL49130554-203045

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
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-URI http://asc.fasb.org/extlink&oid=123351226&loc=SL49130554-203045

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
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-Section 50
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=123351226&loc=SL49130558-203045

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=123351226&loc=SL49130554-203045

+ Details

Leases

9 Months Ended

Sep. 30, 2021

Leases [Abstract]

Leases

The Company has operating and finance leases for corporate and project office spaces, vehicles, heavy machinery and office equipment. Our leases have remaining lease terms of one year to 9 years, some of which may include options to extend the leases for up to five years, and some of which may include options to terminate the leases after the third year.

The components of lease costs for the three and nine months ended September 30, 2021 and September 30, 2020 are as follows (in thousands):

	Three Months Ended						Nine Months Ended
	September 30, 2021			September 30, 2020			September 30, 2021			September 30, 2020
Operating lease cost	$	16,900		$	15,919		$	49,500		$	48,945
Short-term lease cost		3,661			4,301			7,859			12,254
Amortization of right-of-use assets		540			531			1,557			1,036
Interest on lease liabilities		24			64			81			109
Sublease income		(960	)		(959	)		(2,529	)		(2,771	)
Total lease cost	$	20,165		$	19,856		$	56,468		$	59,573

Supplemental cash flow information related to leases for the nine months ended September 30, 2021 and September 30, 2020 is as follows (in thousands):

	Nine Months Ended
	September 30, 2021		September 30, 2020
Operating cash flows for operating leases	$	50,029	$	45,343
Operating cash flows for finance leases		82		111
Financing cash flows from finance leases		1,539		1,080
Right-of-use assets obtained in exchange for new operating lease liabilities		7,456		19,587
Right-of-use assets obtained in exchange for new finance lease liabilities	$	619	$	-

Supplemental balance sheet and other information related to leases as of September 30, 2021 and December 31, 2020 are as follows (in thousands):

	September 30, 2021			December 31, 2020
Operating Leases:
Right-of-use assets	$	188,519		$	210,398
Lease liabilities:
Current	$	54,466		$	54,133
Long-term		157,590			182,467
Total operating lease liabilities	$	212,056		$	236,600
Finance Leases:
Other noncurrent assets	$	3,482		$	3,363
Accrued expenses and other current liabilities	$	1,599		$	1,461
Other long-term liabilities	$	1,708		$	1,733

Weighted Average Remaining Lease Term:
Operating leases	4.5 Years			5 years
Finance leases	2.6 years			3 years
Weighted Average Discount Rate:
Operating leases		3.5	%		3.7	%
Finance leases		2.6	%		3.8	%

As of September 30, 2021, the Company has no operating leases that have not yet commenced.

A maturity analysis of the future undiscounted cash flows associated with the Company’s operating and finance lease liabilities as of September 30, 2021 is as follows (in thousands):

	Operating Leases			Finance Leases
2021 (remaining)	$	15,043		$	449
2022		60,318			1,511
2023		51,645			837
2024		40,809			429
2025		29,941			172
Thereafter		30,812			3
Total lease payments		228,568			3,401
Less: imputed interest		(16,512	)		(94	)
Total present value of lease liabilities	$	212,056		$	3,307

Goodwill

9 Months Ended

Sep. 30, 2021

Goodwill And Intangible Assets Disclosure [Abstract]

Goodwill

The following table summarizes the changes in the carrying value of goodwill by reporting segment from December 31, 2020 to September 30, 2021 (in thousands):

	December 31, 2020		Acquisitions		Foreign Exchange		September 30, 2021
Federal Solutions	$	1,188,882	$	148,770	$	-	$	1,337,652
Critical Infrastructure		73,096		-		717		73,813
Total	$	1,261,978	$	148,770	$	717	$	1,411,465

The ultimate impact from the COVID-19 pandemic is difficult to predict. While many uncertainties exist, we currently anticipate no material change in our financial condition or results of operations. Although the Company does not anticipate a material change to our financial condition or results of operations, the Company performed a qualitative triggering analysis and determined there was no triggering event indicating a potential impairment to the carrying value of its goodwill at September 30, 2021 and concluded there has not been an impairment.

Intangible Assets

9 Months Ended

Sep. 30, 2021

Goodwill And Intangible Assets Disclosure [Abstract]

Intangible Assets

8.	Intangible Assets

The gross amount and accumulated amortization of intangible assets with finite useful lives included in “Intangible assets, net” on the consolidated balance sheets are as follows (in thousands except for years):

	September 30, 2021							December 31, 2020							Weighted Average
	Gross Carrying Amount		Accumulated Amortization			Net Carrying Amount		Gross Carrying Amount		Accumulated Amortization			Net Carrying Amount		Amortization Period (in years)
Backlog	$	169,455	$	(119,308	)	$	50,147	$	145,855	$	(101,038	)	$	44,817		3
Customer relationships		302,829		(146,160	)		156,669		264,129		(110,450	)		153,679		8
Leases		670		(613	)		57		670		(599	)		71		5
Developed technology		113,939		(89,777	)		24,162		112,039		(68,968	)		43,071		4
Trade name		9,200		(8,319	)		881		8,200		(7,967	)		233		1
Non-compete agreements		5,250		(3,111	)		2,139		4,250		(2,043	)		2,207		3
In process research and development		1,800		-			1,800		1,800		-			1,800	n/a
Other intangibles		275		(203	)		72		275		(195	)		80		10
Total intangible assets	$	603,418	$	(367,491	)	$	235,927	$	537,218	$	(291,260	)	$	245,958

The aggregate amortization expense of intangible assets for the three months ended September 30, 2021 and September 30, 2020 was $27.0 million and $20.9 million, respectively, and $76.1 million and $65.7 million for the nine months ended September 30, 2021 and September 30, 2020, respectively.

Estimated amortization expense for the remainder of the current fiscal year and in each of the next four years and beyond is as follows (in thousands):

	September 30, 2021
2021	$	27,130
2022		63,227
2023		49,351
2024		18,862
2025		12,213
Thereafter		63,344
Total	$	234,127

Property and Equipment, Net

9 Months Ended

Sep. 30, 2021

Property Plant And Equipment [Abstract]

Property and Equipment, Net

9.	Property and Equipment, Net

Property and equipment consisted of the following at September 30, 2021 and December 31, 2020 (in thousands):

	September 30, 2021			December 31, 2020			Useful life (years)
Buildings and leasehold improvements	$	99,134		$	98,151		1-15
Furniture and equipment		89,489			91,036		3-10
Computer systems and equipment		162,245			160,305		3-10
Construction equipment		6,842			8,920		5-7
Construction in progress		10,242			9,202
		367,952			367,614
Accumulated depreciation		(262,057	)		(246,587	)
Property and equipment, net	$	105,895		$	121,027

Depreciation expense for the three months ended September 30, 2021 and September 30, 2020 was $9.6 million and $9.5 million, respectively, and $28.8 million and $28.9 million, respectively, for the nine months ended September 30, 2021 and September 30, 2020.

Debt and Credit Facilities

9 Months Ended

Sep. 30, 2021

Debt Disclosure [Abstract]

Debt and Credit Facilities

10.	Debt and Credit Facilities

Debt consisted of the following (in thousands):

	September 30, 2021			December 31, 2020
Short-Term:
Senior notes	$	-		$	50,000
Total Short-Term		-			50,000
Long-Term:
Senior notes		200,000			200,000
Convertible senior notes		400,000			400,000
Debt discount		-			(51,138	)
Debt issuance costs		(8,601	)		(8,864	)
Total long-term		591,399			539,998
Total Debt	$	591,399		$	589,998

Revolving Credit Facility

In June 2021, the Company entered into a $650 million unsecured revolving credit facility (the “Credit Agreement”). The Company incurred $1.9 million of costs in connection with this Credit Agreement. The 2021 Credit Agreement replaced an existing Fifth Amended and Restated Credit Agreement dated as of November 15, 2017. Under the new agreement, the Company’s revolving credit facility was increased from $550 million to $650 million. The credit facility has a five-year maturity, which may be extended up to two times for periods determined by the Company and the applicable extending lenders, and permits the Company to borrow in U.S. dollars, certain specified foreign currencies, and each

other currency that may be approved in accordance with the 2021 Facility. The borrowings under the Credit Agreement bear interest at either a eurocurrency rate plus a margin between 1.0% and 1.625% or a base rate (as defined in the Credit Agreement) plus a margin of between 0% and 0.625%. The rates on September 30, 2021 and December 31, 2020 were 1.34% and 1.87%, respectively. Borrowings under this Credit Agreement are guaranteed by certain Company operating subsidiaries. Letters of credit commitments outstanding under this agreement aggregated to $45.0 million and $44.9 million at September 30, 2021 and December 31, 2020, respectively, which reduced borrowing limits available to the Company. Interest expense related to the Credit Agreement was $0.1 million and $0.2 million for the three months ended September 30, 2021 and September 30, 2020, respectively, and was $0.6 million and $0.9 million for nine months ended September 30, 2021 and September 30, 2020, respectively. There were no loan amounts outstanding under the Credit Agreement on September 30, 2021.

Private Placement

On July 1, 2014, the Company finalized a private placement whereby the Company raised an aggregate amount of $250.0 million in debt as follows (in thousands):

Tranche	Debt Amount		Maturity Date	Interest Rates
Senior Note, Series A	$	50,000	July 15, 2021		4.44	%
Senior Note, Series B		100,000	July 15, 2024		4.98	%
Senior Note, Series C		60,000	July 15, 2026		5.13	%
Senior Note, Series D		40,000	July 15, 2029		5.38	%

The Company incurred $1.1 million of debt issuance costs in connection with the private placement. On August 10, 2018, the Company finalized an amended and restated intercreditor agreement related to this private placement to more closely align certain covenants and definitions with the terms under the 2017 amended and restated Credit Agreement and incurred $0.5 million of additional issuance costs. These costs are presented as a direct deduction from the debt on the face of the consolidated balance sheets. Interest expense related to the Senior Notes for the three months ended September 30, 2021 and September 30, 2020 was $2.7 million and $3.1 million, respectively. Interest expense related to the Senior Notes for the nine months ended September 30, 2021 and September 30, 2020, was $8.9 million and $9.3 million , respectively. The amortization of debt issuance costs and interest expense is recorded in “Interest expense” on the consolidated statements of income. The Company paid the $50 million Series A tranche of the Senior Note as scheduled in July 2021. The Company made interest payments of $6.2 million for both the three months ended September 30, 2021 and September 30, 2020. The Company made interest payments related to the Senior Notes for both the nine months ended September 30, 2021 and September 30, 2020 of $12.4 million. Interest payable of $2.0 million and $5.5 million is recorded in “Accrued expenses and other current liabilities” on the consolidated balance sheets at September 30, 2021 and December 31, 2020, respectively, related to the Senior Notes.

The Credit Agreement and private placement includes various covenants, including restrictions on indebtedness, liens, acquisitions, investments or dispositions, payment of dividends and maintenance of certain financial ratios and conditions. The Company was in compliance with these covenants at September 30, 2021 and December 31, 2020.

The Company also has in place several secondary bank credit lines for issuing letters of credit, principally for foreign contracts, to support performance and completion guarantees. Letters of credit commitments outstanding under these bank lines aggregated $221.2 million and $193.1 million at September 30, 2021 and December 31, 2020, respectively.

Using a discounted cash flow technique that incorporates a market interest yield curve with adjustments for duration, optionality, and risk profile, the Company estimated the fair value (Level 2) of its Senior Notes at September 30, 2021 approximates $223.1 million. See “Note 16 – Fair Value of Financial Instruments” for the definition of Level 2 of the fair value hierarchy.

Convertible Senior Notes

In August 2020, the Company issued an aggregate $400.0 million of 0.25% Convertible Senior Notes due 2025, including the exercise of a $50.0 million initial purchasers’ option. The Company received proceeds from the issuance and sale of the Convertible Senior Notes of $389.7 million, net of $10.3 million of transaction fees and other third-party offering expenses. The Convertible Senior Notes accrue interest at a rate of 0.25% per annum, payable semi-annually on February 15 and August 15 of each year beginning on February 15, 2021, and will mature on August 15, 2025, unless earlier repurchased, redeemed or converted.

The Convertible Senior Notes are the Company’s senior unsecured obligations and will rank senior in right of payment to any of the Company’s indebtedness that is expressly subordinated in right of payment to the Notes; equal in right of payment to any of the Company’s unsecured indebtedness that is not so subordinated; effectively junior in right of payment to any of the Company’s secured indebtedness, to the extent of the value of the assets securing such indebtedness; and structurally junior to all indebtedness and other liabilities (including trade payables) of the Company’s subsidiaries

Each $1,000 of principal of the Notes will initially be convertible into 22.2913 shares of our common stock, which is equivalent to an initial conversion price of $44.86 per share, subject to adjustment upon the occurrence of specified events. On or after March 15, 2025 until the close of business on the second scheduled trading day immediately preceding the maturity date of the Convertible Senior Notes, holders may convert all or a portion of their Convertible Senior Notes, regardless of the conditions below.

Prior to the close of business on the business day immediately preceding March 15, 2025, the Notes will be convertible at the option of the holders thereof only under the following circumstances:

•

during any calendar quarter commencing after the calendar quarter ending on December 31, 2020, if the last reported sale price of the Company’s common stock for at least 20 trading days, whether or not consecutive, during a period of 30 consecutive trading days ending on, and including the last trading day of the immediately preceding calendar quarter, is greater than or equal to 130% of the conversion price on each applicable trading day;

•

during the five business day period after any five consecutive trading day period in which, for each trading day of that period, the trading price per $1,000 principal amount of Convertible Senior Notes for such trading day was less than 98% of the product of the last reported sale price of the Company’s common stock and the conversion rate on each such trading day;

•

if the Company calls such Convertible Senior Notes for redemption; or

•

upon the occurrence of specified corporate events described in the Indenture.

The Company may redeem all or any portion of the Convertible Senior Notes for cash, at its option, on or after August 21, 2023 and before the 51^st scheduled trading day immediately before the maturity date at a redemption price equal to 100% of the principal amount of the Notes to be redeemed, plus accrued and unpaid interest, but only if the last reported sale price per share of the Company’s common stock exceeds 130% of the conversion price for a specified period of time. In addition, calling any Convertible Senior Note for redemption will constitute a Make-Whole Fundamental Change with respect to that Convertible Senior Note, in which case the conversion rate applicable to the conversion of that Convertible Senior Note will be increased in certain circumstances if it is converted after it is called for redemption.

Upon the occurrence of a fundamental change prior to the maturity date of the Convertible Senior Notes, holders of the Convertible Senior Notes may require the Company to repurchase all or a portion of the Convertible Senior Notes for cash at a price equal to 100% of the principal amount of the Convertible Senior Notes to be repurchased, plus any accrued and unpaid interest to, but excluding, the fundamental change repurchase date.

Upon conversion, the Company may settle the Convertible Senior Notes for cash, shares of the Company’s common stock, or a combination thereof, at the Company’s option. If the Company satisfies its conversion obligation solely in cash or through payment and delivery of a combination of cash and shares of the Company’s common stock, the amount of cash and shares of common stock due upon conversion will be based on a daily conversion value calculated on a proportionate basis for each trading day in a 50-trading day observation period.

Under existing GAAP at the time of issuance during 2020, convertible debt instruments that may be settled in cash on conversion were required to be separated into liability and equity components in a manner that reflects the issuer’s non-convertible debt borrowing rate. The carrying amount of the liability component is based on the fair value of a similar instrument that does not contain an equity conversion option. The carrying amount allocated to the equity component, which is recognized as a debt discount, represents the difference between the proceeds from the issuance of the notes

and the fair value of the liability component of the notes. Based on this debt to equity ratio, debt issuance costs are then allocated to the liability and equity components in a similar manner. Accordingly, at issuance the Company allocated $336.1 million to the debt liability and $53.6 million to additional paid-in capital. The difference between the principal amount of the Convertible Senior Notes and the liability component, inclusive of issuance costs, represents the debt discount, which the Company amortized to interest expense over the term of the Convertible Senior Notes using an effective interest rate of 3.25%. During the year ended December 31, 2020, the Company recognized interest expense of $4.4 million. As of December 31, 2020, the net carrying value of the Notes was $340.6 million.

In the first quarter of 2021, the Company early adopted ASU 2020-06, “Debt – Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging – Contracts in Equity’s Own Equity (Subtopic 815-40)”. The Company used the modified retrospective method which resulted in a reduction in non-cash interest expense and reclassification of equity component of the convertible senior notes of $55.0 million and equity component of the debt issuance costs of $1.4 million to liabilities on the consolidated balance sheet. The Company also adjusted the carrying amount of the convertible senior notes to what it would have been if the Company had applied ASU 2020-06 from the inception of the Notes and recorded the offset of the carrying amount adjustment of $3.7 million in retained earnings on January 1, 2021. The Company recognized interest expense of $0.7 million and $1.6 million for the three months ended September 30, 2021 and September 30, 2020, respectively, and $2.2 million and $1.6 million for the nine months ended September 30, 2021 and September 30, 2020, respectively. As of September 30, 2021, the carrying value of the Notes was $400.0 million.

Convertible Note Hedge and Warrant Transactions

In connection with the sale of the Convertible Senior Notes, the Company purchased a bond hedge designed to mitigate the potential dilution from the conversion of the Convertible Senior Notes. Under the five-year term of the bond hedge, upon a conversion of the bonds, the Company will receive the number of shares of common stock equal to the remaining common stock deliverable upon conversion of the Convertible Senior Notes if the conversion value exceeds the principal amount of the Notes. The aggregate number of shares that the Company could be obligated to issue upon conversion of the Convertible Senior Notes is approximately 8.9 million shares. The cost of the convertible note hedge transactions was $55.0 million.

The cost of the convertible note hedge was partially offset by the Company’s sale of warrants to acquire approximately 8.9 million shares of the Company’s common stock. The warrants were initially exercisable at a price of at least $66.46 per share and are subject to customary adjustments upon the occurrence of certain events, such as the payment of dividends. The Company received $13.8 million in cash proceeds from the sales of these warrants.

The bond hedge and warrant transactions effectively increased the conversion price associated with the Convertible Senior Notes during the term of these transactions from 35%, or $44.86, to 100%, or $66.46, at their issuance, thereby reducing the dilutive economic effect to shareholders upon actual conversion.

The bond hedges and warrants are indexed to, and potentially settled in, shares of the Company’s common stock. The net cost of $41.2 million for the purchase of the bond hedges and sale of the warrants was recorded as a reduction to additional paid-in capital in the consolidated balance sheets.

At issuance, the Company recorded a deferred tax liability of $16.2 million related to the Convertible Senior Notes debt discount and the capitalized debt issuance costs. The Company also recorded a deferred tax asset of $16.5 million related to the convertible note hedge transactions and the tax basis of the capitalized debt issuance costs through additional paid-in capital. The deferred tax liability and deferred tax asset were included net in “Deferred tax assets” on the consolidated balance sheets. Upon adoption of ASU2020-06, the Company reversed the deferred tax liability of $13.9 million that the Company had recorded at issuance related to the Convertible Senior Note debt discount and recorded an additional deferred tax liability of $0.4 million related to the capitalized debt issuance costs. In addition, the Company recorded a $0.9 million adjustment to the deferred tax asset through retained earnings related to the tax effect of book accretion recorded in 2020 and reversed upon adoption.

- Definition

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-URI http://asc.fasb.org/topic&trid=2208564

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1B
-Subparagraph (h)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1C
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495334-112611

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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-Subparagraph (a)
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-Paragraph 1I
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-Paragraph 1
-Subparagraph (SX 210.4-08(c))
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+ Details

Income Taxes

9 Months Ended

Sep. 30, 2021

Income Tax Disclosure [Abstract]

Income Taxes

11.	Income Taxes

The Company’s effective tax rate was 25.5% and 25.6% for the three months ended September 30, 2021 and 2020, respectively. The decrease in the effective tax rate was due primarily to an increase in untaxed income attributable to noncontrolling interests, release of a valuation allowance on foreign tax credits utilized on the 2020 federal return, and a change in jurisdictional earnings, partially offset by a write down of a foreign tax receivable. The Company’s effective tax rate for the nine months ended September 30, 2021 and September 30, 2020 was 25.8% and 26.4%. The decrease in effective tax rate was due primarily to an increase in untaxed income attributed to noncontrolling interests, release of a valuation allowance on foreign tax credits utilized on the 2020 federal return, and a change in jurisdictional earnings, partially offset by a write down of a foreign tax receivable. The difference between the effective tax rate and the statutory U.S. Federal income tax rate of 21.0% for the three and nine months ended September 30, 2021 primarily relates to state income taxes, a valuation allowance recorded against foreign tax credit carryovers, and a write down of the foreign tax receivable, partially offset by tax benefits related to untaxed income attributable to noncontrolling interests and federal research tax credits.

As of September 30, 2021, the Company’s deferred tax assets were subject to a valuation allowance of $32.0 million primarily related to foreign net operating loss carryforwards, foreign tax credit carryforwards, and capital losses that the Company has determined are not more-likely-than-not to be realized. The factors used to assess the likelihood of realization include: the past performance of the entities, forecasts of future taxable income, future reversals of existing taxable temporary differences, and available tax planning strategies that could be implemented to realize the deferred tax assets. The ability or failure to achieve the forecasted taxable income in these entities could affect the ultimate realization of deferred tax assets.

As of September 30, 2021 and December 31, 2020, the liability for income taxes associated with uncertain tax positions was $17.6 million and $16.4 million, respectively. It is reasonably possible that the Company may realize a decrease in our uncertain tax positions of approximately $0.2 million during the next 12 months as a result of various tax audits and closing tax years.

Although the Company believes its reserves for its tax positions are reasonable, the final outcome of tax audits could be materially different, both favorably and unfavorably. It is reasonably possible that certain audits may conclude in the next 12 months and that the unrecognized tax benefits the Company has recorded in relation to these tax years may change compared to the liabilities recorded for these periods. However, it is not currently possible to estimate the amount, if any, of such change.

- Definition

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.

+ References

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+ Details

Contingencies

9 Months Ended

Sep. 30, 2021

Commitments And Contingencies Disclosure [Abstract]

Contingencies

12.	Contingencies

The Company is subject to certain lawsuits, claims and assessments that arise in the ordinary course of business. Additionally, the Company has been named as a defendant in lawsuits alleging personal injuries as a result of contact with asbestos products at various project sites. Management believes that any significant costs relating to these claims will be reimbursed by applicable insurance and, although there can be no assurance that these matters will be resolved favorably, management believes that the ultimate resolution of any of these claims will not have a material adverse effect on our consolidated financial position, results of operations, or cash flows. A liability is recorded when it is both probable that a loss has been incurred and the amount of loss or range of loss can be reasonably estimated. When using a range of loss estimate, the Company records the liability using the low end of the range. The Company records a corresponding receivable for costs covered under its insurance policies. Management judgment is required to determine the outcome and the estimated amount of a loss related to such matters. Management believes that there are no claims or assessments outstanding which would materially affect the consolidated results of operations or the Company’s financial position.

On or about March 1, 2017, the Peninsula Corridor Joint Powers Board, or the JPB, filed a lawsuit against Parsons Transportation Group, Inc., or PTG, in the Superior Court of California, County of San Mateo, in connection with a positive train control project on which PTG was engaged prior to termination of its contract by the JPB. PTG had previously filed a lawsuit against the JPB for breach of contract and wrongful termination. The JPB sought damages in excess of $100.0 million, which the Company disputed. In addition to filing a complaint for breach of contract and wrongful termination, the Company denied the allegations raised by the JPB and, accordingly, filed affirmative defenses. During the third quarter of 2021, the Company and JPB entered into a settlement agreement resolving their disputes against each other. The Company intends to pursue further recovery against one of its subcontractors. At this time, the Company is unable to determine the probability of the outcome of the litigation or determine a potential range of loss, if any.

In September 2015, a former Parsons employee filed an action in the United States District Court for the Northern District of Alabama against us as a qui tam relator on behalf of the United States (the “Relator”) alleging violation of the False Claims Act. The United States government did not intervene in this matter as it is allowed to do so under the statute. The Company filed a motion to dismiss the lawsuit on the grounds that the Relator did not meet the applicable statute of limitations. The District Court granted the motion to dismiss. The Relator’s attorney appealed the decision to the United States Court of Appeals of the Eleventh Circuit, which ultimately ruled in favor of the Relator, and the Company petitioned the United States Supreme Court to review the decision. The Supreme Court reviewed the decision and accepted the position of the Relator. The case was thus remanded to the United States District Court for the Northern District of Alabama. The defendants, including Parsons, will file appropriate pleadings opposing the allegations. At this time, the Company is unable to determine the probability of the outcome of the litigation or determine a potential range of loss, if any.

Federal government contracts are subject to audits, which are performed for the most part by the Defense Contract Audit Agency (“DCAA”). Audits by the DCAA and other agencies consist of reviews of our overhead rates, operating systems and cost proposals to ensure that we account for such costs in accordance with the Cost Accounting Standards (“CAS”). If the DCAA determines we have not accounted for such costs in accordance with the CAS, the DCAA may disallow these costs. The disallowance of such costs may result in a reduction of revenue and additional liability for the Company. Historically, the Company has not experienced any material disallowed costs as a result of government audits. However, the Company can provide no assurance that the DCAA or other government audits will not result in material disallowances for incurred costs in the future. All audits of costs incurred on work performed through 2013 have been closed, and years thereafter remain open.

Although there can be no assurance that these matters will be resolved favorably, management believes that their ultimate resolution will not have a material adverse impact on the Company’s consolidated financial position, results of operations, or cash flows.

Retirement Benefit Plan

9 Months Ended

Sep. 30, 2021

Compensation And Retirement Disclosure [Abstract]

Retirement Benefit Plan

13.	Retirement Benefit Plan

The Company’s principal retirement benefit plan is the Parsons Employee Stock Ownership Plan (“ESOP”), a stock bonus plan, established in 1975 to cover eligible employees of the Company and certain affiliated companies. Contributions of treasury stock to the ESOP are made annually in amounts determined by the Company’s board of directors and are held in trust for the sole benefit of the participants. Shares allocated to a participant’s account are fully vested after three years of credited service, or in the event(s) of reaching age 65, death or disability while an active employee of the Company. As of September 30, 2021 and December 31, 2020, total shares of the Company’s common stock outstanding were 102,257,780 and 102,360,662, respectively, of which 69,719,214 and 76,641,312, respectively, were held by the ESOP.

A participant’s interest in their ESOP account is redeemable upon certain events, including retirement, death, termination due to permanent disability, a severe financial hardship following termination of employment, certain conflicts of interest following termination of employment, or the exercise of diversification rights. Distributions from the ESOP of participants’ interests are made in the Company’s common stock based on quoted prices of a share of the Company’s common stock on the NYSE. A participant will be able to sell such shares of common stock in the market, subject to any requirements of the federal securities laws.

Total ESOP contribution expense was $14.8 million and $12.5 million for the three months ended September 30, 2021 and September 30, 2020, respectively, and $41.3 million and $42.0 million for the nine months ended September 30, 2021 and September 30, 2020, respectively. The expense is recorded in “Direct costs of contracts” and “Selling, general and administrative expense” in the consolidated statements of income. The fiscal 2021 ESOP contribution has not yet been made. The amount is currently included in accrued liabilities.

Investments in and Advances to Joint Ventures

9 Months Ended

Sep. 30, 2021

Equity Method Investments And Joint Ventures [Abstract]

Investments in and Advances to Joint Ventures

14.	Investments in and Advances to Joint Ventures

The Company participates in joint ventures to bid, negotiate and complete specific projects. The Company is required to consolidate these joint ventures if it holds the majority voting interest or if the Company meets the criteria under the consolidation model, as described below.

The Company performs an analysis to determine whether its variable interests give the Company a controlling financial interest in a Variable Interest Entity (“VIE”) for which the Company is the primary beneficiary and should,

therefore, be consolidated. Such analysis requires the Company to assess whether it has the power to direct the activities of the VIE and the obligation to absorb losses or the right to receive benefits that could potentially be significant to the VIE.

The Company analyzed all of its joint ventures and classified them into two groups: (1) joint ventures that must be consolidated because they are either not VIEs and the Company holds the majority voting interest, or because they are VIEs and the Company is the primary beneficiary; and (2) joint ventures that do not need to be consolidated because they are either not VIEs and the Company holds a minority voting interest, or because they are VIEs and the Company is not the primary beneficiary.

Many of the Company’s joint venture agreements provide for capital calls to fund operations, as necessary; however, such funding is infrequent and is not anticipated to be material.

Letters of credit outstanding described in “Note 10 – Debt and Credit Facilities” that relate to project ventures are $75.0 million and $59.3 million at September 30, 2021 and December 31, 2020, respectively.

In the table below, aggregated financial information relating to the Company’s joint ventures is provided because their nature, risk and reward characteristics are similar. None of the Company’s current joint ventures that meet the characteristics of a VIE are individually significant to the consolidated financial statements.

Consolidated Joint Ventures

The following represents financial information for consolidated joint ventures included in the consolidated financial statements (in thousands):

	September 30, 2021		December 31, 2020
Current assets	$	253,105	$	292,407
Noncurrent assets		1,856		2,990
Total assets		254,961		295,397
Current liabilities		194,543		201,270
Total liabilities		194,543		201,270
Total joint venture equity	$	60,418	$	94,127

	Three Months Ended				Nine Months Ended
	September 30, 2021		September 30, 2020		September 30, 2021		September 30, 2020
Revenue	$	101,816	$	117,344	$	296,685	$	335,511
Costs		86,726		105,223		260,129		304,308
Net income	$	15,090	$	12,121	$	36,556	$	31,203
Net income attributable to noncontrolling interests	$	7,411	$	5,862	$	17,711	$	15,086

The assets of the consolidated joint ventures are restricted for use only by the particular joint venture and are not available for the Company’s general operations.

Unconsolidated Joint Ventures

The Company accounts for its unconsolidated joint ventures using the equity method of accounting. Under this method, the Company recognizes its proportionate share of the net earnings of these joint ventures as “Equity in earnings (loss) of unconsolidated joint ventures” in the consolidated statements of income. The Company’s maximum exposure to loss as a result of its investments in unconsolidated joint ventures is typically limited to the aggregate of the carrying value of the investment and future funding commitments.

The following represents the financial information of the Company’s unconsolidated joint ventures as presented in their unaudited financial statements (in thousands):

	September 30, 2021		December 31, 2020
Current assets	$	1,103,345	$	774,646
Noncurrent assets		554,366		585,802
Total assets		1,657,711		1,360,448
Current liabilities		789,072		703,287
Noncurrent liabilities		562,523		517,697
Total liabilities		1,351,595		1,220,984
Total joint venture equity	$	306,116	$	139,464
Investments in and advances to unconsolidated joint ventures	$	102,677	$	68,975

	Three Months Ended				Nine Months Ended
	September 30, 2021		September 30, 2020		September 30, 2021		September 30, 2020
Revenue	$	728,461	$	594,640	$	1,701,262	$	1,286,087
Costs		697,493		551,624		1,604,538		1,202,315
Net income	$	30,968	$	43,016	$	96,724	$	83,772
Equity in earnings of unconsolidated joint ventures	$	9,570	$	16,741	$	26,528	$	26,624

The Company had net contributions to its unconsolidated joint ventures for the three months ended September 30, 2021, of $7.3 million and received net distributions from its unconsolidated joint ventures for the three months ended September 30, 2020, of $11.2 million. The Company had net contributions to its unconsolidated joint ventures for the nine months ended September 30, 2021 of $0.5 million and received net distributions from its unconsolidated joint ventures for the nine months ended September 30, 2020 of $23.2 million.

For the three and nine months ended September 30, 2021, the Company recorded write-downs of $5.5 million and $10.6 million, respectively, on an unconsolidated joint venture in the Critical Infrastructure segment as a result of changes in estimates made by the managing partner. The write-downs decreased operating and net income by $5.5 million and $4.1 million, respectively for the three months ended September 2021. Operating and net income were decreased by $10.6 million and $7.9 million, respectively, for the nine months ended September 30, 2021. The write-downs decreased diluted earnings per share by $0.04 and $0.07 for the three and nine months ended September 30, 2021.

Related Party Transactions

9 Months Ended

Sep. 30, 2021

Related Party Transactions

15.	Related Party Transactions

The Company often provides services to unconsolidated joint ventures and revenues include amounts related to recovering costs for these services. Revenues related to services the Company provided to unconsolidated joint ventures for the three months ended September 30, 2021 and September 30, 2020 were $37.1 million and $42.0 million, respectively, and for the nine months ended September 30, 2021 and September 30, 2020 were $119.5 million and $124.7 million, respectively. For the three months ended September 30, 2021 and September 30, 2020, the Company incurred $29.0 million and $32.3 million, respectively, and for the nine months ended September 30, 2021 and September 30, 2020, $90.9 million and $98.3 million, respectively, of reimbursable costs. Amounts included in the consolidated balance sheets related to services the Company provided to unconsolidated joint ventures are as follows (in thousands):

	September 30, 2021		December 31, 2020
Accounts receivable	$	28,799	$	37,544
Contract assets		7,835		8,889
Contract liabilities		9,188		5,720

Fair Value of Financial Instruments

9 Months Ended

Sep. 30, 2021

Fair Value Disclosures [Abstract]

Fair Value of Financial Instruments

16.	Fair Value of Financial Instruments

The authoritative guidance on fair value measurement defines fair value as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date (referred to as an “exit price”). At September 30, 2021 and December 31, 2020, the Company’s financial instruments include cash, cash equivalents, accounts receivable, accounts payable, and other liabilities. The fair values of these financial instruments approximate their carrying values due to their short-term maturities.

Investments measured at fair value are based on one or more of the following three valuation techniques:

•

Market approach—Prices and other relevant information generated by market transactions involving identical or comparable assets or liabilities;

•

Cost approach—Amount that would be required to replace the service capacity of an asset (i.e., replacement cost); and

•

Income approach—Techniques to convert future amounts to a single present amount based on market expectations (including present value techniques, option-pricing models and lattice models).

In addition, the guidance establishes a fair value hierarchy that prioritizes the inputs to valuation techniques used to measure fair value. The hierarchy gives the highest priority to unadjusted quoted market prices in active markets for identical assets and liabilities (Level 1 measurements) and the lowest priority to unobservable inputs (Level 3 measurements). The three levels of the fair value hierarchy are:

Level 1

Unadjusted quoted prices in active markets that are accessible at the measurement date for identical assets and liabilities;

Level 2

Pricing inputs that include quoted prices for similar assets and liabilities in active markets and inputs that are observable for the asset or liability, either directly or indirectly, for substantially the full term of the instrument; and

Level 3

Prices or valuations that require inputs that are both significant to the fair value measurements and unobservable.

The methods described above may produce a fair value calculation that may not be indicative of net realizable value or reflective of future fair values. Furthermore, while the Company believes its valuation methods are appropriate and consistent with other market participants, the use of different methodologies or assumptions to determine the fair value of certain financial instruments could result in a different fair value measurement at the reporting date.

Refer to Notes to Consolidated Financial Statements included in the Company’s Form 10-K for the year ended December 31, 2020 for a more complete discussion of the various items within the consolidated financial statements measured at fair value and the methods used to determine fair value.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Earnings Per Share

9 Months Ended

Sep. 30, 2021

Earnings Per Share [Abstract]

Earnings Per Share

17.	Earnings Per Share

The following tables reconcile the denominator and numerator used to compute basic earnings per share (“EPS”) to the denominator and numerator used to compute diluted EPS for the three and nine months ended September 30, 2021 and September 30, 2020. Basic EPS is computed using the weighted average number of shares outstanding during the period and income available to shareholders. Diluted EPS is computed similar to basic EPS, except the income available to shareholders is adjusted to add back interest expense, after tax, related to the Convertible Senior Note, and the weighted average number of shares outstanding is adjusted to reflect the dilutive effects of stock-based awards and shares underlying the Convertible Senior Note.

Convertible Senior Note dilution impact is calculated using the if-converted method which was required upon adoption of ASU 2020-06. As a result, the Company elected to adopt the if-converted method when the Convertible Senior Notes were issued during the third quarter of 2020. In connection with the offerings of the Notes, the Company entered into a convertible note hedge and warrants (see Note 10 Debt and Credit Facilities); however, the convertible note hedge is not considered when calculating dilutive shares given its impact is anti-dilutive. The impact of the bond hedge would offset the dilutive impact of the shares underlying the Convertible Senior Note. The warrants have a strike price above our average share price during the period and are out of the money and not included in the tables below.

Dilutive potential common shares include shares the Company could be obligated to issue from its Convertible Senior Notes and warrants (see Note 10 for further discussion) and stock-based awards. Shares to be provided to the Company from its bond hedge purchased concurrently with the issuance of Convertible Senior Notes are anti-dilutive and are not included in its diluted shares. Anti-dilutive stock-based awards excluded from the calculation of earnings per share for the three months ended September 30, 2021 and September 30, 2020 were 4,656 and 205, respectively, and for the nine months ended September 30, 2021 and September 30, 2020 were 6,838 and 3,318, respectively. In addition, the convertible senior notes were anti-dilutive and excluded for the nine months ended September 30, 2020.

The weighted average number of shares used to compute basic and diluted EPS were:

	Three Months Ended				Nine Months Ended
	September 30, 2021		September 30, 2020		September 30, 2021		September 30, 2020
Basic weighted average number of shares outstanding		102,478,095		100,736,862		102,463,511		100,700,498
Stock-based awards		751,807		378,486		637,686		321,070
Convertible senior notes		8,916,530		4,458,265		8,916,530		-
Diluted weighted average number of shares outstanding		112,146,432		105,573,613		112,017,727		101,021,568

The net income available to shareholders to compute basic and diluted EPS were (in thousands):

	Three Months Ended				Nine Months Ended
	September 30, 2021		September 30, 2020		September 30, 2021		September 30, 2020
Net income attributable to Parsons Corporation		19,358		40,658		35,099		76,930
Convertible senior notes if-converted method interest adjustment		534		1,164		1,593		-
Diluted net income attributable to Parsons Corporation		19,892		41,822		36,692		76,930

Share Repurchases

In August 2021, the Company’s Board of Directors authorized a stock repurchase program to repurchase up to $100.0 million of shares of Commons stock. Repurchases under this stock repurchase program commenced on August 12, 2021. Any and all shares of Common Stock purchased by the Company pursuant to the program shall be retired upon their acquisition and shall not become treasury shares but instead shall resume the status of authorized but unissued shares of Common Stock. The table below presents information on this repurchase program:

	Nine Months Ended
	September 30, 2021
Total shares repurchased		245,000
Total shares retired		245,000
Average price paid per share	$	35.51

As of September 30, 2021, the Company has $91.3 million remaining under the stock repurchase program.

Segment Information

9 Months Ended

Sep. 30, 2021

Segment Reporting [Abstract]

Segment Information

18.	Segment Information

The Company operates in two reportable segments: Federal Solutions and Critical Infrastructure.

The Federal Solutions segment provides advanced technical solutions to the U.S. government, delivering timely, cost-effective hardware, software and services for mission-critical projects. The segment provides advanced technologies, supporting national security missions in cybersecurity, missile defense, and military facility modernization, logistics support, hazardous material remediation and engineering services.

The Critical Infrastructure segment provides integrated engineering and management services for complex physical and digital infrastructure around the globe. The Critical Infrastructure segment is a technology innovator focused on next generation digital systems and complex structures. Industry leading capabilities in engineering and project

management allow the Company to deliver significant value to customers by employing cutting-edge technologies, improving timelines and reducing costs.

The Company defines its reportable segments based on the way the chief operating decision maker (“CODM”), its Chairman and Chief Executive Officer, evaluates the performance of each segment and manages the operations of the Company for purposes of allocating resources among the segments. The CODM evaluates segment operating performance using segment Revenue and segment Adjusted EBITDA attributable to Parsons Corporation.

The following table summarizes business segment revenue for the periods presented (in thousands):

	Three Months Ended				Nine Months Ended
	September 30, 2021		September 30, 2020		September 30, 2021		September 30, 2020
Federal Solutions revenue	$	499,291	$	498,156	$	1,394,035	$	1,457,937
Critical Infrastructure revenue		456,759		506,080		1,316,068		1,496,751
Total revenue	$	956,050	$	1,004,236	$	2,710,103	$	2,954,688

The Company defines Adjusted EBITDA attributable to Parsons Corporation as Adjusted EBITDA excluding Adjusted EBITDA attributable to noncontrolling interests. The Company defines Adjusted EBITDA as net income (loss) attributable to Parsons Corporation, adjusted to include net income (loss) attributable to noncontrolling interests and to exclude interest expense (net of interest income), provision for income taxes, depreciation and amortization and certain other items that are not considered in the evaluation of ongoing operating performance. These other items include net income (loss) attributable to noncontrolling interests, asset impairment charges, equity-based compensation, income and expense recognized on litigation matters, expenses incurred in connection with acquisitions and other non-recurring transaction costs and expenses related to our prior restructuring. The following table reconciles business segment Adjusted EBITDA attributable to Parsons Corporation to Net Income attributable to Parsons Corporation for the periods presented (in thousands):

	Three Months Ended						Nine Months Ended
Adjusted EBITDA attributable to Parsons Corporation	September 30, 2021			September 30, 2020			September 30, 2021			September 30, 2020
Federal Solutions	$	46,481		$	45,874		$	110,963		$	125,191
Critical Infrastructure		30,371			48,856			89,845			111,732
Adjusted EBITDA attributable to Parsons Corporation		76,852			94,730			200,808			236,923
Adjusted EBITDA attributable to noncontrolling interests		7,540			6,071			18,010			15,535
Depreciation and amortization		(37,232	)		(30,952	)		(106,540	)		(95,442	)
Interest expense, net		(3,987	)		(5,387	)		(13,188	)		(13,144	)
Income tax expense		(9,165	)		(16,017	)		(18,378	)		(32,992	)
Equity-based compensation expense		(3,224	)		991			(15,125	)		(4,142	)
Transaction-related costs (a)		(2,537	)		(2,411	)		(9,269	)		(11,937	)
Restructuring expense (b)		(357	)		(365	)		(507	)		(1,475	)
Other (c)		(1,121	)		(140	)		(3,001	)		(1,310	)
Net income including noncontrolling interests		26,769			46,520			52,810			92,016
Net income attributable to noncontrolling interests		7,411			5,862			17,711			15,086
Net income attributable to Parsons Corporation	$	19,358		$	40,658		$	35,099		$	76,930

(a)	Reflects costs incurred in connection with acquisitions and other non-recurring transaction costs, primarily fees paid for professional services and employee retention.

(b)	Reflects costs associated with corporate restructuring initiatives.

(c)	Includes a combination of gain/loss related to sale of fixed assets, software implementation costs, and other individually insignificant items that are non-recurring in nature.

Asset information by segment is not a key measure of performance used by the CODM.

The following tables present revenues and property and equipment, net by geographic area (in thousands):

	Three Months Ended				Nine Months Ended
	September 30, 2021		September 30, 2020		September 30, 2021		September 30, 2020
Revenue
North America	$	804,122	$	831,367	$	2,245,515	$	2,429,357
Middle East		147,207		168,043		448,525		511,591
Rest of World		4,721		4,826		16,063		13,740
Total Revenue	$	956,050	$	1,004,236	$	2,710,103	$	2,954,688

The geographic location of revenue is determined by the location of the customer.

	September 30, 2021		December 31, 2020
Property and Equipment, Net
North America	$	102,352	$	116,460
Middle East		3,543		4,567
Total Property and Equipment, Net	$	105,895	$	121,027

North America includes revenue in the United States for the three months ended September 30, 2021 and September 30, 2020 of $730.7 million and $774.0 million, respectively, and for the nine months ended September 30, 2021 and September 30, 2020 of $2.0 billion and $2.2 billion, respectively. North America property and equipment, net includes $96.7 million and $109.6 million of property and equipment, net in the United States at September 30, 2021 and December 31, 2020, respectively.

The following table presents revenues by business units (in thousands):

	Three Months Ended				Nine Months Ended
	September 30, 2021		September 30, 2020		September 30, 2021		September 30, 2020
Revenue
Defense and Intelligence	$	343,151	$	333,289	$	962,642	$	953,755
Engineered Systems		156,140		164,867		431,393		504,182
Federal Solutions revenues		499,291		498,156		1,394,035		1,457,937
Connected Communities		91,902		116,366		263,106		316,626
Mobility Solutions		364,857		389,714		1,052,962		1,180,125
Critical Infrastructure revenues		456,759		506,080		1,316,068		1,496,751
Total Revenue	$	956,050	$	1,004,236	$	2,710,103	$	2,954,688

Effective July 1, 2021, the Company made changes to its Federal Solutions business units by consolidating Space & Geospatial Solutions, Cyber & Intelligence, and Missile Defense & C5ISR into a new Defense and Intelligence business unit. The prior year information in the table above has been reclassified to conform to the business line changes.

- Definition

The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 31
-URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e8924-108599

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 21
-Subparagraph (a)
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Subparagraph (e)
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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-Publisher FASB
-Name Accounting Standards Codification
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-Name Accounting Standards Codification
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Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e8657-108599

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
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-URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e8721-108599

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/topic&trid=2134510

+ Details

Subsequent Events

9 Months Ended

Sep. 30, 2021

Subsequent Events [Abstract]

Subsequent Events

19.	Subsequent Events

None.

Basis of Presentation and Principles of Consolidation (Policies)	9 Months Ended
	Sep. 30, 2021
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Basis of Presentation and Principles of Consolidation	The accompanying unaudited consolidated financial statements and related notes of the Company have been prepared in accordance with generally accepted accounting principles in the United States of America ("GAAP") and pursuant to the interim period reporting requirements of Form 10-Q. They do not include all of the information and footnotes required by GAAP for complete financial statements and, therefore, should be read in conjunction with our consolidated financial statements and the notes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2020. In the opinion of management, the consolidated financial statements reflect all normal recurring adjustments necessary for a fair statement of the financial position, results of operations and cash flows for the interim periods presented. The results of operations and cash flows for any interim period are not necessarily indicative of results for the full year or for future years. This Quarterly Report on Form 10-Q includes the accounts of Parsons Corporation and its subsidiaries and affiliates which it controls. Interests in joint ventures that are controlled by the Company, or for which the Company is otherwise deemed to be the primary beneficiary, are consolidated. For joint ventures in which the Company does not have a controlling interest, but exerts a significant influence, the Company applies the equity method of accounting (see “Note 14 – Investments in and Advances to Joint Ventures" for further discussion). Intercompany accounts and transactions are eliminated in consolidation.
Use of Estimates	Use of Estimates The preparation of the consolidated financial statements in accordance with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual amounts could differ from those estimates. The Company’s most significant estimates and judgments involve revenue recognition with respect to the determination of the costs to complete contracts and transaction price; determination of self-insurance reserves; useful lives of property and equipment and intangible assets; calculation of allowance for doubtful accounts; valuation of deferred income tax assets and uncertain tax positions, among others. Please see “Management’s Discussion and Analysis of Financial Condition and Results of Operations—Critical Accounting Policies and Estimates” and “Note 2—Summary of Significant Accounting Polices” in the notes to our consolidated financial statements included in the Company’s Form 10-K for the year ended December 31, 2020, for a discussion of the significant estimates and assumptions affecting our consolidated financial statements. Estimates of costs to complete contracts are continually evaluated as work progresses and are revised when necessary. When a change in estimate is determined to have an impact on contract profit, the Company records a positive or negative adjustment to the consolidated statement of income.
Employee Stock Purchase Plan	Employee Stock Purchase Plan During the second quarter of fiscal 2020, initial purchases of the Company’s common Stock were made under the Parsons Employee Stock Purchase Program (“ESPP”). Under the ESPP, eligible employees who elect to participate are granted the right to purchase shares of the common stock of Parsons at a discount that is limited to 5% of the per-share market value on the day shares are sold to employees. Purchases of common stock under the ESPP are included in “proceeds from issuance of common stock” in cash flows from financing activities in the Consolidated Statements of Cash Flows.
Stock Repurchase Plan	Stock Repurchase Plan During the third quarter of 2021, the Company’s Board of Directors authorized the Company to acquire a number of shares of Common Stock having an aggregate market value of not greater than $100,000,000 from time to time. Repurchased shares of common stock are retired and included in “Repurchases of common stock” in cash flows from financing activities in the Consolidated Statements of Cash Flows.
New Accounting Pronouncements	In the first quarter of 2021, the Company early adopted Accounting Standards Update (“ASU”) ASU 2020-06, Debt – Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging – Contracts in Entity’s Own Equity (Subtopic 815-40) (“ASU 2020-06)”. The update simplifies the accounting for convertible debt instruments and convertible preferred stock by reducing the number of accounting models and limiting the number of embedded conversion features separately recognized from the primary contract. The guidance also includes targeted improvements to the disclosures for convertible instruments and earnings per share. ASU 2020-06 is effective for fiscal years beginning after December 15, 2021, including interim periods within those fiscal years. Early adoption is permitted, but no earlier than fiscal years beginning after December 15, 2020. The Company adopted ASU 2020-06 in the first quarter of 2021 using the modified retrospective method which resulted in a reduction in non-cash interest expense and reclassification of the equity portion of the Convertible Senior Notes to “Long-term debt” on the consolidated balance sheet. In the first quarter of 2021, the Company adopted ASU No. 2019-12, “Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes (“ASU 2019-12”)”. ASU 2019-12 was issued as a means to reduce the complexity of accounting for income taxes. The guidance is to be applied using a prospective method, excluding amendments related to franchise taxes, which should be applied on either a retrospective basis for all periods presented or a modified retrospective basis through a cumulative-effect adjustment to retained earnings as of the beginning of the fiscal year of adoption. The adoption of ASU 2019-12 did not have a material impact on the consolidated financial statements. In the first quarter of 2020, the Company adopted ASU 2016-13, “Measurement of Credit Losses on Financial Instruments.” The amendments in ASU 2016-13 replaced the incurred loss impairment methodology in current practice with a methodology that reflects expected credit losses and requires consideration of a broader range of reasonable and supportable information to estimate credit losses. The adoption of ASU 2016-13 did not have a material impact on the consolidated financial statements.
Leases	Leases The Company has operating and finance leases for corporate and project office spaces, vehicles, heavy machinery and office equipment. Our leases have remaining lease terms of one year to 9 years, some of which may include options to extend the leases for up to five years, and some of which may include options to terminate the leases after the third year.

Acquisitions (Tables)

9 Months Ended

Sep. 30, 2021

BlackHorse Solutions, Inc.

Summary of Estimated Fair Values of Assets Acquired and Liabilities Assumed on Preliminary Purchase Price Allocation

The following table summarizes the estimated fair values of the assets acquired and liabilities assumed based on the purchase price allocation as of the date of acquisition (in thousands):

	Amount
Cash and cash equivalents	$	15,428
Accounts receivable		3,351
Contract assets		5,979
Prepaid expenses and other current assets		977
Property and equipment		2,278
Right of use assets, operating leases		6,157
Goodwill		142,948
Intangible assets		65,000
Accounts payable		(2,326	)
Accrued expenses and other current liabilities		(17,197	)
Contract liabilities		(320	)
Short-term lease liabilities, operating leases		(1,011	)
Long-term lease liabilities, operating leases		(5,146	)
Deferred tax liabilities		(11,091	)
Net assets acquired	$	205,027

Schedule of Intangible Assets Value on Purchase Price

Of the total purchase price, the following values were assigned to intangible assets (in thousands, except for years):

	Gross Carrying Amount		Amortization Period
			(in years)
Customer relationships	$	40,000	16
Backlog		22,000	3
Trade name		1,000	2
Developed technologies		1,000	3
Non-compete agreements		1,000	3

Schedule of Supplemental Pro Forma Information

Supplemental information of unaudited pro forma operating results assuming the BlackHorse acquisition had been consummated as of the beginning of fiscal year 2020 (in thousands) is as follows:

	Three Months Ended				Nine Months Ended
	September 30, 2021		September 30, 2020		September 30, 2021		September 30, 2020
Pro forma Revenue	$	957,498	$	1,017,325	$	2,748,559	$	2,988,153
Pro forma Net Income including noncontrolling interests		31,070		45,195	$	56,694	$	82,921

Braxton Science & Technology Group

Summary of Estimated Fair Values of Assets Acquired and Liabilities Assumed on Preliminary Purchase Price Allocation

The following table summarizes the estimated fair values of the assets acquired and liabilities assumed based on the purchase price allocation as of the date of acquisition (in thousands):

	Amount
Cash and cash equivalents	$	7,006
Accounts receivable		18,163
Contract assets		8,350
Prepaid expenses and other current assets		3,036
Property and equipment		5,114
Right of use assets, operating leases		10,788
Goodwill		212,185
Intangible assets		74,950
Accounts payable		(7,464	)
Accrued expenses and other current liabilities		(9,845	)
Contract liabilities		(300	)
Short-term lease liabilities, operating leases		(1,915	)
Long-term lease liabilities, operating leases		(8,873	)
Deferred tax liabilities		(1,694	)
Net assets acquired	$	309,501

Schedule of Intangible Assets Value on Purchase Price

Of the total purchase price, the following values were assigned to intangible assets (in thousands, except for years):

Schedule of Supplemental Pro Forma Information

Supplemental information of unaudited pro forma operating results assuming the Braxton acquisition had been consummated as of the beginning of fiscal year 2019 (in thousands) is as follows:

	Three Months Ended				Nine Months Ended
	September 30, 2021		September 30, 2020		September 30, 2021		September 30, 2020
Pro forma Revenue	$	956,050	$	1,046,002	$	2,710,103	$	3,050,708
Pro forma Net Income including noncontrolling interests		27,463		48,072	$	55,391	$	93,672

Contracts with Customers (Tables)

9 Months Ended

Sep. 30, 2021

Revenue From Contract With Customer [Abstract]

Summary of Disaggregation of Revenue

	Three Months Ended				Nine Months Ended
	September 30, 2021		September 30, 2020		September 30, 2021		September 30, 2020
Fixed-Price	$	246,894	$	324,901	$	710,067	$	944,577
Time-and-Materials		261,566		265,987		754,596		777,807
Cost-Plus		447,590		413,348		1,245,440		1,232,304
Total	$	956,050	$	1,004,236	$	2,710,103	$	2,954,688

Summary of Contract Assets and Contract Liabilities

Contract assets and contract liabilities balances at September 30, 2021 and December 31, 2020 were as follows (in thousands):

	September 30, 2021		December 31, 2020		$ change			% change
Contract assets	$	569,294	$	576,568	$	(7,274	)		-1.3	%
Contract liabilities		186,789		201,864		(15,075	)		-7.5	%
Net contract assets (liabilities) (1)	$	382,505	$	374,704	$	7,801			2.1	%

(1)

Summary of Changes in Contract Assets and Contract Liabilities

Certain changes in contract assets and contract liabilities consisted of the following:

	September 30, 2021		December 31, 2020
Acquired contract assets	$	5,979	$	8,350
Acquired contract liabilities		320		300

Summary of Changes in Revenue

	Three Months Ended						Nine Months Ended
	September 30, 2021			September 30, 2020			September 30, 2021			September 30, 2020
Revenue impact, net	$	(6,300	)	$	(134	)	$	(27,553	)	$	8,848

Summary of Accounts Receivable, Net

Accounts receivable, net consisted of the following as of September 30, 2021 and December 31, 2020 (in thousands):

	2021			2020
Billed	$	443,024		$	512,357
Unbilled		188,428			190,222
Total accounts receivable, gross		631,452			702,579
Allowance for doubtful accounts		(4,007	)		(4,001	)
Total accounts receivable, net	$	627,445		$	698,578

Summary of Remaining Unsatisfied Performance Obligations Expect to Satisfy

The Company expects to satisfy its RUPO as of September 30, 2021 over the following periods (in thousands):

Period RUPO Will Be Satisfied	Within One Year		Within One to Two Years		Thereafter
Federal Solutions	$	1,418,783	$	787,273	$	491,797
Critical Infrastructure		1,452,760		781,669		1,021,928
Total	$	2,871,543	$	1,568,942	$	1,513,725

Leases (Tables)

9 Months Ended

Sep. 30, 2021

Leases [Abstract]

Summary of Lease Costs

The components of lease costs for the three and nine months ended September 30, 2021 and September 30, 2020 are as follows (in thousands):

	Three Months Ended						Nine Months Ended
	September 30, 2021			September 30, 2020			September 30, 2021			September 30, 2020
Operating lease cost	$	16,900		$	15,919		$	49,500		$	48,945
Short-term lease cost		3,661			4,301			7,859			12,254
Amortization of right-of-use assets		540			531			1,557			1,036
Interest on lease liabilities		24			64			81			109
Sublease income		(960	)		(959	)		(2,529	)		(2,771	)
Total lease cost	$	20,165		$	19,856		$	56,468		$	59,573

Schedule of Supplemental Cash Flow Information Related to Leases

Supplemental cash flow information related to leases for the nine months ended September 30, 2021 and September 30, 2020 is as follows (in thousands):

	Nine Months Ended
	September 30, 2021		September 30, 2020
Operating cash flows for operating leases	$	50,029	$	45,343
Operating cash flows for finance leases		82		111
Financing cash flows from finance leases		1,539		1,080
Right-of-use assets obtained in exchange for new operating lease liabilities		7,456		19,587
Right-of-use assets obtained in exchange for new finance lease liabilities	$	619	$	-

Schedule of Supplemental Balance Sheet and Other Information Related to Leases

Supplemental balance sheet and other information related to leases as of September 30, 2021 and December 31, 2020 are as follows (in thousands):

	September 30, 2021			December 31, 2020
Operating Leases:
Right-of-use assets	$	188,519		$	210,398
Lease liabilities:
Current	$	54,466		$	54,133
Long-term		157,590			182,467
Total operating lease liabilities	$	212,056		$	236,600
Finance Leases:
Other noncurrent assets	$	3,482		$	3,363
Accrued expenses and other current liabilities	$	1,599		$	1,461
Other long-term liabilities	$	1,708		$	1,733

Weighted Average Remaining Lease Term:
Operating leases	4.5 Years			5 years
Finance leases	2.6 years			3 years
Weighted Average Discount Rate:
Operating leases		3.5	%		3.7	%
Finance leases		2.6	%		3.8	%

Schedule of Maturity Analysis of Future Undiscounted Cash Flows

A maturity analysis of the future undiscounted cash flows associated with the Company’s operating and finance lease liabilities as of September 30, 2021 is as follows (in thousands):

	Operating Leases			Finance Leases
2021 (remaining)	$	15,043		$	449
2022		60,318			1,511
2023		51,645			837
2024		40,809			429
2025		29,941			172
Thereafter		30,812			3
Total lease payments		228,568			3,401
Less: imputed interest		(16,512	)		(94	)
Total present value of lease liabilities	$	212,056		$	3,307

Goodwill (Tables)

9 Months Ended

Sep. 30, 2021

Goodwill And Intangible Assets Disclosure [Abstract]

Summary of Changes in Carrying Value of Goodwill by Reporting Segment

The following table summarizes the changes in the carrying value of goodwill by reporting segment from December 31, 2020 to September 30, 2021 (in thousands):

	December 31, 2020		Acquisitions		Foreign Exchange		September 30, 2021
Federal Solutions	$	1,188,882	$	148,770	$	-	$	1,337,652
Critical Infrastructure		73,096		-		717		73,813
Total	$	1,261,978	$	148,770	$	717	$	1,411,465

Intangible Assets (Tables)

9 Months Ended

Sep. 30, 2021

Goodwill And Intangible Assets Disclosure [Abstract]

Schedule of Gross Amount and Accumulated Amortization of Intangible Assets

	September 30, 2021							December 31, 2020							Weighted Average
	Gross Carrying Amount		Accumulated Amortization			Net Carrying Amount		Gross Carrying Amount		Accumulated Amortization			Net Carrying Amount		Amortization Period (in years)
Backlog	$	169,455	$	(119,308	)	$	50,147	$	145,855	$	(101,038	)	$	44,817		3
Customer relationships		302,829		(146,160	)		156,669		264,129		(110,450	)		153,679		8
Leases		670		(613	)		57		670		(599	)		71		5
Developed technology		113,939		(89,777	)		24,162		112,039		(68,968	)		43,071		4
Trade name		9,200		(8,319	)		881		8,200		(7,967	)		233		1
Non-compete agreements		5,250		(3,111	)		2,139		4,250		(2,043	)		2,207		3
In process research and development		1,800		-			1,800		1,800		-			1,800	n/a
Other intangibles		275		(203	)		72		275		(195	)		80		10
Total intangible assets	$	603,418	$	(367,491	)	$	235,927	$	537,218	$	(291,260	)	$	245,958

Schedule of Estimated Amortization Expense

Estimated amortization expense for the remainder of the current fiscal year and in each of the next four years and beyond is as follows (in thousands):

	September 30, 2021
2021	$	27,130
2022		63,227
2023		49,351
2024		18,862
2025		12,213
Thereafter		63,344
Total	$	234,127

Property and Equipment, Net (Tables)

9 Months Ended

Sep. 30, 2021

Property Plant And Equipment [Abstract]

Schedule of Property and Equipment, Net

Property and equipment consisted of the following at September 30, 2021 and December 31, 2020 (in thousands):

	September 30, 2021			December 31, 2020			Useful life (years)
Buildings and leasehold improvements	$	99,134		$	98,151		1-15
Furniture and equipment		89,489			91,036		3-10
Computer systems and equipment		162,245			160,305		3-10
Construction equipment		6,842			8,920		5-7
Construction in progress		10,242			9,202
		367,952			367,614
Accumulated depreciation		(262,057	)		(246,587	)
Property and equipment, net	$	105,895		$	121,027

Debt and Credit Facilities (Tables)

9 Months Ended

Sep. 30, 2021

Debt Disclosure [Abstract]

Schedule of Debt

Debt consisted of the following (in thousands):

	September 30, 2021			December 31, 2020
Short-Term:
Senior notes	$	-		$	50,000
Total Short-Term		-			50,000
Long-Term:
Senior notes		200,000			200,000
Convertible senior notes		400,000			400,000
Debt discount		-			(51,138	)
Debt issuance costs		(8,601	)		(8,864	)
Total long-term		591,399			539,998
Total Debt	$	591,399		$	589,998

Schedule of Aggregate Amount of Debt

On July 1, 2014, the Company finalized a private placement whereby the Company raised an aggregate amount of $250.0 million in debt as follows (in thousands):

Tranche	Debt Amount		Maturity Date	Interest Rates
Senior Note, Series A	$	50,000	July 15, 2021		4.44	%
Senior Note, Series B		100,000	July 15, 2024		4.98	%
Senior Note, Series C		60,000	July 15, 2026		5.13	%
Senior Note, Series D		40,000	July 15, 2029		5.38	%

Investments in and Advances to Joint Ventures (Tables)

9 Months Ended

Sep. 30, 2021

Equity Method Investments And Joint Ventures [Abstract]

Schedule of Financial Information of Consolidated Joint Ventures

The following represents financial information for consolidated joint ventures included in the consolidated financial statements (in thousands):

	September 30, 2021		December 31, 2020
Current assets	$	253,105	$	292,407
Noncurrent assets		1,856		2,990
Total assets		254,961		295,397
Current liabilities		194,543		201,270
Total liabilities		194,543		201,270
Total joint venture equity	$	60,418	$	94,127

	Three Months Ended				Nine Months Ended
	September 30, 2021		September 30, 2020		September 30, 2021		September 30, 2020
Revenue	$	101,816	$	117,344	$	296,685	$	335,511
Costs		86,726		105,223		260,129		304,308
Net income	$	15,090	$	12,121	$	36,556	$	31,203
Net income attributable to noncontrolling interests	$	7,411	$	5,862	$	17,711	$	15,086

Summary of Financial Information for Unconsolidated Joint Ventures

The following represents the financial information of the Company’s unconsolidated joint ventures as presented in their unaudited financial statements (in thousands):

	September 30, 2021		December 31, 2020
Current assets	$	1,103,345	$	774,646
Noncurrent assets		554,366		585,802
Total assets		1,657,711		1,360,448
Current liabilities		789,072		703,287
Noncurrent liabilities		562,523		517,697
Total liabilities		1,351,595		1,220,984
Total joint venture equity	$	306,116	$	139,464
Investments in and advances to unconsolidated joint ventures	$	102,677	$	68,975

	Three Months Ended				Nine Months Ended
	September 30, 2021		September 30, 2020		September 30, 2021		September 30, 2020
Revenue	$	728,461	$	594,640	$	1,701,262	$	1,286,087
Costs		697,493		551,624		1,604,538		1,202,315
Net income	$	30,968	$	43,016	$	96,724	$	83,772
Equity in earnings of unconsolidated joint ventures	$	9,570	$	16,741	$	26,528	$	26,624

Related Party Transactions (Tables)

9 Months Ended

Sep. 30, 2021

Schedule of Consolidated Balance Sheet Related to Services Provided to Unconsolidated Joint Ventures

Amounts included in the consolidated balance sheets related to services the Company provided to unconsolidated joint ventures are as follows (in thousands):

	September 30, 2021		December 31, 2020
Accounts receivable	$	28,799	$	37,544
Contract assets		7,835		8,889
Contract liabilities		9,188		5,720

Earnings Per Share (Tables)

9 Months Ended

Sep. 30, 2021

Earnings Per Share [Abstract]

Schedule of Weighted Average Number of Shares Used To Compute Basic and Diluted EPS

The weighted average number of shares used to compute basic and diluted EPS were:

	Three Months Ended				Nine Months Ended
	September 30, 2021		September 30, 2020		September 30, 2021		September 30, 2020
Basic weighted average number of shares outstanding		102,478,095		100,736,862		102,463,511		100,700,498
Stock-based awards		751,807		378,486		637,686		321,070
Convertible senior notes		8,916,530		4,458,265		8,916,530		-
Diluted weighted average number of shares outstanding		112,146,432		105,573,613		112,017,727		101,021,568

Net Income Available to Shareholders to Compute Basic and Diluted EPS

The net income available to shareholders to compute basic and diluted EPS were (in thousands):

	Three Months Ended				Nine Months Ended
	September 30, 2021		September 30, 2020		September 30, 2021		September 30, 2020
Net income attributable to Parsons Corporation		19,358		40,658		35,099		76,930
Convertible senior notes if-converted method interest adjustment		534		1,164		1,593		-
Diluted net income attributable to Parsons Corporation		19,892		41,822		36,692		76,930

Schedule of Repurchase Program

The table below presents information on this repurchase program:

	Nine Months Ended
	September 30, 2021
Total shares repurchased		245,000
Total shares retired		245,000
Average price paid per share	$	35.51

Segment Information (Tables)

9 Months Ended

Sep. 30, 2021

Segment Reporting [Abstract]

Summary of Business Segment Information

The following table summarizes business segment revenue for the periods presented (in thousands):

	Three Months Ended				Nine Months Ended
	September 30, 2021		September 30, 2020		September 30, 2021		September 30, 2020
Federal Solutions revenue	$	499,291	$	498,156	$	1,394,035	$	1,457,937
Critical Infrastructure revenue		456,759		506,080		1,316,068		1,496,751
Total revenue	$	956,050	$	1,004,236	$	2,710,103	$	2,954,688

Summary of Adjusted EBITDA Business Segment Information

The following table reconciles business segment Adjusted EBITDA attributable to Parsons Corporation to Net Income attributable to Parsons Corporation for the periods presented (in thousands):

	Three Months Ended						Nine Months Ended
Adjusted EBITDA attributable to Parsons Corporation	September 30, 2021			September 30, 2020			September 30, 2021			September 30, 2020
Federal Solutions	$	46,481		$	45,874		$	110,963		$	125,191
Critical Infrastructure		30,371			48,856			89,845			111,732
Adjusted EBITDA attributable to Parsons Corporation		76,852			94,730			200,808			236,923
Adjusted EBITDA attributable to noncontrolling interests		7,540			6,071			18,010			15,535
Depreciation and amortization		(37,232	)		(30,952	)		(106,540	)		(95,442	)
Interest expense, net		(3,987	)		(5,387	)		(13,188	)		(13,144	)
Income tax expense		(9,165	)		(16,017	)		(18,378	)		(32,992	)
Equity-based compensation expense		(3,224	)		991			(15,125	)		(4,142	)
Transaction-related costs (a)		(2,537	)		(2,411	)		(9,269	)		(11,937	)
Restructuring expense (b)		(357	)		(365	)		(507	)		(1,475	)
Other (c)		(1,121	)		(140	)		(3,001	)		(1,310	)
Net income including noncontrolling interests		26,769			46,520			52,810			92,016
Net income attributable to noncontrolling interests		7,411			5,862			17,711			15,086
Net income attributable to Parsons Corporation	$	19,358		$	40,658		$	35,099		$	76,930

(a)	Reflects costs incurred in connection with acquisitions and other non-recurring transaction costs, primarily fees paid for professional services and employee retention.

(b)	Reflects costs associated with corporate restructuring initiatives.

(c)	Includes a combination of gain/loss related to sale of fixed assets, software implementation costs, and other individually insignificant items that are non-recurring in nature.

Summary of Revenues and Property and Equipment, Net by Geographic Area

The following tables present revenues and property and equipment, net by geographic area (in thousands):

	Three Months Ended				Nine Months Ended
	September 30, 2021		September 30, 2020		September 30, 2021		September 30, 2020
Revenue
North America	$	804,122	$	831,367	$	2,245,515	$	2,429,357
Middle East		147,207		168,043		448,525		511,591
Rest of World		4,721		4,826		16,063		13,740
Total Revenue	$	956,050	$	1,004,236	$	2,710,103	$	2,954,688

The geographic location of revenue is determined by the location of the customer.

	September 30, 2021		December 31, 2020
Property and Equipment, Net
North America	$	102,352	$	116,460
Middle East		3,543		4,567
Total Property and Equipment, Net	$	105,895	$	121,027

Summary of Revenues by Business Lines

The following table presents revenues by business units (in thousands):

	Three Months Ended				Nine Months Ended
	September 30, 2021		September 30, 2020		September 30, 2021		September 30, 2020
Revenue
Defense and Intelligence	$	343,151	$	333,289	$	962,642	$	953,755
Engineered Systems		156,140		164,867		431,393		504,182
Federal Solutions revenues		499,291		498,156		1,394,035		1,457,937
Connected Communities		91,902		116,366		263,106		316,626
Mobility Solutions		364,857		389,714		1,052,962		1,180,125
Critical Infrastructure revenues		456,759		506,080		1,316,068		1,496,751
Total Revenue	$	956,050	$	1,004,236	$	2,710,103	$	2,954,688

Basis of Presentation and Principles of Consolidation - Additional Information (Details) - Maximum - USD ($)	3 Months Ended
	Jun. 30, 2020	Sep. 30, 2021
Basis Of Presentation And Principles Of Consolidation Disclosure [Line Items]
Number of authorized shares of common stock value		$ 100,000,000
Employee Stock Purchase Plan
Basis Of Presentation And Principles Of Consolidation Disclosure [Line Items]
Percentage of per-share market value limit for share purchases	5.00%

New Accounting Pronouncements - Additional Information (Details)	Sep. 30, 2021
ASU 2020-06
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Change in accounting principle, accounting standards update, adoption date	Jan. 01, 2021
Change in accounting principle, accounting standards update, early adoption	true
Change in accounting principle, accounting standards update, immaterial effect	false
ASU 2019-12
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Change in accounting principle, accounting standards update, adoption date	Jan. 01, 2021
Change in accounting principle, accounting standards update, immaterial effect	true
Change in accounting principle, accounting standards update, adopted	true
ASU 2016-13
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Change in accounting principle, accounting standards update, adoption date	Jan. 01, 2020
Change in accounting principle, accounting standards update, immaterial effect	true
Change in accounting principle, accounting standards update, adopted	true

- Definition

Indicates (true false) whether accounting standards update was adopted.

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- Definition

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+ Details

Acquisitions - Additional Information (Details) - USD ($) $ in Thousands				3 Months Ended		9 Months Ended
	Jul. 30, 2021	Jul. 06, 2021	Nov. 19, 2020	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Business Acquisition [Line Items]
Amortization of intangible assets				$ 27,000	$ 20,900	$ 76,100	$ 65,700
Revenues				956,050	$ 1,004,236	2,710,103	$ 2,954,688
Goodwill				1,411,465		1,411,465		$ 1,261,978
BlackHorse Solutions, Inc.
Business Acquisition [Line Items]
Percentage of ownership interest acquired		100.00%
Cash paid to acquire		$ 205,000
Amortization of intangible assets				2,600
Goodwill deductible for tax purposes		10,600
Revenues				16,700
Goodwill		$ 142,948
Echo Ridge LLC
Business Acquisition [Line Items]
Percentage of ownership interest acquired	100.00%
Cash paid to acquire	$ 9,000
Goodwill	$ 7,200
Braxton Science & Technology Group
Business Acquisition [Line Items]
Percentage of ownership interest acquired			100.00%
Cash paid to acquire			$ 309,500
Amortization of intangible assets				4,000		12,100
Goodwill deductible for tax purposes			196,300
Revenues				34,000		94,300
Goodwill			$ 212,185
Selling, General and Administrative Expense \| BlackHorse Solutions, Inc.
Business Acquisition [Line Items]
Acquisition related expenses				3,000
Selling, General and Administrative Expense \| Echo Ridge LLC
Business Acquisition [Line Items]
Acquisition related expenses				$ 300
Selling, General and Administrative Expense \| Braxton Science & Technology Group
Business Acquisition [Line Items]
Acquisition related expenses						$ 600

Acquisitions - Summary of Estimated Fair Values of Assets Acquired and Liabilities Assumed on Preliminary Purchase Price Allocation (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Jul. 06, 2021	Dec. 31, 2020	Nov. 19, 2020
Business Acquisition [Line Items]
Contract assets	$ 569,294		$ 576,568
Goodwill	1,411,465		1,261,978
Contract liabilities	$ (186,789)		$ (201,864)
BlackHorse Solutions, Inc.
Business Acquisition [Line Items]
Cash and cash equivalents		$ 15,428
Accounts receivable		3,351
Contract assets		5,979
Prepaid expenses and other current assets		977
Property and equipment		2,278
Right of use assets, operating leases		6,157
Goodwill		142,948
Intangible assets		65,000
Accounts payable		(2,326)
Accrued expenses and other current liabilities		(17,197)
Contract liabilities		(320)
Short-term lease liabilities, operating leases		(1,011)
Long-term lease liabilities, operating leases		(5,146)
Deferred tax liabilities		(11,091)
Net assets acquired		$ 205,027
Braxton Science & Technology Group
Business Acquisition [Line Items]
Cash and cash equivalents				$ 7,006
Accounts receivable				18,163
Contract assets				8,350
Prepaid expenses and other current assets				3,036
Property and equipment				5,114
Right of use assets, operating leases				10,788
Goodwill				212,185
Intangible assets				74,950
Accounts payable				(7,464)
Accrued expenses and other current liabilities				(9,845)
Contract liabilities				(300)
Short-term lease liabilities, operating leases				(1,915)
Long-term lease liabilities, operating leases				(8,873)
Deferred tax liabilities				(1,694)
Net assets acquired				$ 309,501

Acquisitions - Schedule of Intangible Assets Value on Purchase Price (Details) - USD ($) $ in Thousands			9 Months Ended
	Jul. 06, 2021	Nov. 19, 2020	Sep. 30, 2021
Customer Relationships
Acquired Finite Lived Intangible Assets [Line Items]
Amortization Period (in years)			8 years
Customer Relationships \| BlackHorse Solutions, Inc.
Acquired Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 40,000
Amortization Period (in years)	16 years
Customer Relationships \| Braxton Science & Technology Group
Acquired Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount		$ 34,100
Amortization Period (in years)		12 years
Backlog
Acquired Finite Lived Intangible Assets [Line Items]
Amortization Period (in years)			3 years
Backlog \| BlackHorse Solutions, Inc.
Acquired Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 22,000
Amortization Period (in years)	3 years
Backlog \| Braxton Science & Technology Group
Acquired Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount		$ 38,200
Amortization Period (in years)		3 years
Trade Names
Acquired Finite Lived Intangible Assets [Line Items]
Amortization Period (in years)			1 year
Trade Names \| BlackHorse Solutions, Inc.
Acquired Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 1,000
Amortization Period (in years)	2 years
Non compete Agreements
Acquired Finite Lived Intangible Assets [Line Items]
Amortization Period (in years)			3 years
Non compete Agreements \| BlackHorse Solutions, Inc.
Acquired Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 1,000
Amortization Period (in years)	3 years
Non compete Agreements \| Braxton Science & Technology Group
Acquired Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount		$ 650
Amortization Period (in years)		3 years
Developed Technologies
Acquired Finite Lived Intangible Assets [Line Items]
Amortization Period (in years)			4 years
Developed Technologies \| BlackHorse Solutions, Inc.
Acquired Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 1,000
Amortization Period (in years)	3 years
Developed Technologies \| Braxton Science & Technology Group
Acquired Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount		$ 2,000
Amortization Period (in years)		6 years

Acquisitions - Schedule of Supplemental Pro Forma Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
BlackHorse Solutions, Inc.
Business Acquisition [Line Items]
Pro forma Revenue	$ 957,498	$ 1,017,325	$ 2,748,559	$ 2,988,153
Pro forma Net Income including noncontrolling interests	31,070	45,195	56,694	82,921
Braxton Science & Technology Group
Business Acquisition [Line Items]
Pro forma Revenue	956,050	1,046,002	2,710,103	3,050,708
Pro forma Net Income including noncontrolling interests	$ 27,463	$ 48,072	$ 55,391	$ 93,672

Contracts with Customers - Summary of Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Disaggregation Of Revenue [Line Items]
Revenues	$ 956,050	$ 1,004,236	$ 2,710,103	$ 2,954,688
Fixed-Price
Disaggregation Of Revenue [Line Items]
Revenues	246,894	324,901	710,067	944,577
Time-and-Materials
Disaggregation Of Revenue [Line Items]
Revenues	261,566	265,987	754,596	777,807
Cost-Plus
Disaggregation Of Revenue [Line Items]
Revenues	$ 447,590	$ 413,348	$ 1,245,440	$ 1,232,304

- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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-URI http://asc.fasb.org/extlink&oid=6472922&loc=d3e499488-122856

+ Details

Contracts with Customers - Summary of Contract Assets and Contract Liabilities (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Dec. 31, 2020
Revenue From Contract With Customer [Abstract]
Contract assets	$ 569,294	$ 576,568
Contract liabilities	186,789	201,864
Net contract assets (liabilities)	382,505	$ 374,704
Change in contract assets	(7,274)
Change in contract liabilities	(15,075)
Change in contract assets and liabilities	$ 7,801
Percentage change in contract assets	(1.30%)
Percentage change in contract liabilities	(7.50%)
Percentage change in contract assets and liabilities	2.10%

Contracts with Customers - Summary of Contract Assets and Contract Liabilities (Parenthetical) (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Revenue From Contract With Customer [Abstract]
Contract retentions	$ 94.3	$ 93.8
Contract retentions, not expected to be paid in next 12 months	52.3
Contract assets, unapproved change orders, claims, and requests	$ 106.0	$ 116.6

Contracts with Customers - Additional Information (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Revenue From Contract With Customer [Abstract]
Revenue recognized included contract liability	$ 3,000,000.0	$ 9,500,000	$ 95,500,000	$ 132,200,000
Impairment of contract assets	0	$ 0	0	$ 0
Impact of changes in estimated claims or incentives on revenue			5,000,000
Remaining unsatisfied performance obligations	$ 6,000,000,000.0		$ 6,000,000,000.0

Contracts with Customers - Summary of Changes in Contract Assets and Contract Liabilities (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2021	Dec. 31, 2020
Revenue From Contract With Customer [Abstract]
Acquired contract assets	$ 5,979	$ 8,350
Acquired contract liabilities	$ 320	$ 300

Contracts with Customers - Summary of Changes in Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Revenue From Contract With Customer [Abstract]
Revenue impact, net	$ (6,300)	$ (134)	$ (27,553)	$ 8,848

Contracts with Customers - Summary of Accounts Receivable, Net (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Revenue From Contract With Customer [Abstract]
Billed	$ 443,024	$ 512,357
Unbilled	188,428	190,222
Total accounts receivable, gross	631,452	702,579
Allowance for doubtful accounts	(4,007)	(4,001)
Total accounts receivable, net	$ 627,445	$ 698,578

Leases - Additional Information (Details)	9 Months Ended
Leases - Additional Information (Details)	Sep. 30, 2021 USD ($)
Lessee Lease Description [Line Items]
Lease option to extend	five years
Lease existence of option to extend	true
Lease option to terminate	third year
Lease existence of option to terminate	true
Operating lease not yet commenced expense	$ 0
Minimum
Lessee Lease Description [Line Items]
Lease term of contract	1 year
Maximum
Lessee Lease Description [Line Items]
Lease term of contract	9 years

Leases - Summary of Lease Costs (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Leases [Abstract]
Operating lease cost	$ 16,900	$ 15,919	$ 49,500	$ 48,945
Short-term lease cost	3,661	4,301	7,859	12,254
Amortization of right-of-use assets	540	531	1,557	1,036
Interest on lease liabilities	24	64	81	109
Sublease income	(960)	(959)	(2,529)	(2,771)
Total lease cost	$ 20,165	$ 19,856	$ 56,468	$ 59,573

Leases - Schedule of Supplemental Cash Flow Information Related to Leases (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Leases [Abstract]
Operating cash flows for operating leases	$ 50,029	$ 45,343
Operating cash flows for finance leases	82	111
Financing cash flows from finance leases	1,539	1,080
Right-of-use assets obtained in exchange for new operating lease liabilities	7,456	19,587
Right-of-use assets obtained in exchange for new finance lease liabilities	$ 619	$ 0

Leases - Schedule of Supplemental Balance Sheet and Other Information Related to Leases (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Operating Leases:
Right-of-use assets	$ 188,519	$ 210,398
Lease liabilities:
Current	54,466	54,133
Long-term	157,590	182,467
Total operating lease liabilities	212,056	236,600
Finance Leases:
Other noncurrent assets	3,482	3,363
Accrued expenses and other current liabilities	$ 1,599	$ 1,461
Finance Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	us-gaap:OtherLiabilitiesCurrent	us-gaap:OtherLiabilitiesCurrent
Other long-term liabilities	$ 1,708	$ 1,733
Finance Lease, Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration]	Other long-term liabilities	Other long-term liabilities
Weighted Average Remaining Lease Term:
Operating leases	4 years 6 months	5 years
Finance leases	2 years 7 months 6 days	3 years
Weighted Average Discount Rate:
Operating leases	3.50%	3.70%
Finance leases	2.60%	3.80%

Leases - Schedule of Maturity Analysis of Future Undiscounted Cash Flows (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Operating Leases
2021 (remaining)	$ 15,043
2022	60,318
2023	51,645
2024	40,809
2025	29,941
Thereafter	30,812
Total lease payments	228,568
Less: imputed interest	(16,512)
Total present value of lease liabilities	212,056	$ 236,600
Finance Leases
2021 (remaining)	449
2022	1,511
2023	837
2024	429
2025	172
Thereafter	3
Total lease payments	3,401
Less: imputed interest	(94)
Total present value of lease liabilities	$ 3,307

Goodwill - Summary of Changes in Carrying Value of Goodwill by Reporting Segment (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2021 USD ($)
Goodwill [Line Items]
Beginning Balance	$ 1,261,978
Acquisitions	148,770
Foreign Exchange	717
Ending Balance	1,411,465
Federal Solutions
Goodwill [Line Items]
Beginning Balance	1,188,882
Acquisitions	148,770
Ending Balance	1,337,652
Critical Infrastructure
Goodwill [Line Items]
Beginning Balance	73,096
Foreign Exchange	717
Ending Balance	$ 73,813

Goodwill - Additional Information (Details)	9 Months Ended
Goodwill - Additional Information (Details)	Sep. 30, 2021 USD ($)
Goodwill And Intangible Assets Disclosure [Abstract]
Impairment of goodwill	$ 0

Intangible Assets - Schedule of Gross Amount and Accumulated Amortization of Intangible Assets (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Dec. 31, 2020
Acquired Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 603,418	$ 537,218
Accumulated Amortization	(367,491)	(291,260)
Net Carrying Amount	235,927	245,958
Backlog
Acquired Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	169,455	145,855
Accumulated Amortization	(119,308)	(101,038)
Net Carrying Amount	$ 50,147	44,817
Amortization Period (in years)	3 years
Customer Relationships
Acquired Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 302,829	264,129
Accumulated Amortization	(146,160)	(110,450)
Net Carrying Amount	$ 156,669	153,679
Amortization Period (in years)	8 years
Leases
Acquired Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 670	670
Accumulated Amortization	(613)	(599)
Net Carrying Amount	$ 57	71
Amortization Period (in years)	5 years
Developed Technology
Acquired Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 113,939	112,039
Accumulated Amortization	(89,777)	(68,968)
Net Carrying Amount	$ 24,162	43,071
Amortization Period (in years)	4 years
Trade Name
Acquired Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 9,200	8,200
Accumulated Amortization	(8,319)	(7,967)
Net Carrying Amount	$ 881	233
Amortization Period (in years)	1 year
Non compete Agreements
Acquired Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 5,250	4,250
Accumulated Amortization	(3,111)	(2,043)
Net Carrying Amount	$ 2,139	2,207
Amortization Period (in years)	3 years
In Process Research and Development
Acquired Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 1,800	1,800
Accumulated Amortization		0
Net Carrying Amount	1,800	1,800
Other Intangibles
Acquired Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	275	275
Accumulated Amortization	(203)	(195)
Net Carrying Amount	$ 72	$ 80
Amortization Period (in years)	10 years

Intangible Assets - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Goodwill And Intangible Assets Disclosure [Abstract]
Amortization expense of intangible assets	$ 27.0	$ 20.9	$ 76.1	$ 65.7

Intangible Assets - Schedule of Estimated Amortization Expense (Details) $ in Thousands	Sep. 30, 2021 USD ($)
Goodwill And Intangible Assets Disclosure [Abstract]
2021	$ 27,130
2022	63,227
2023	49,351
2024	18,862
2025	12,213
Thereafter	63,344
Finite-Lived Intangible Assets, Net	$ 234,127

Property and Equipment, Net - Schedule of Property and Equipment, Net (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Dec. 31, 2020
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 367,952	$ 367,614
Accumulated depreciation	(262,057)	(246,587)
Property and equipment, net	105,895	121,027
Buildings and Leasehold Improvements
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 99,134	98,151
Buildings and Leasehold Improvements \| Minimum
Property Plant And Equipment [Line Items]
Useful life (years)	1 year
Buildings and Leasehold Improvements \| Maximum
Property Plant And Equipment [Line Items]
Useful life (years)	15 years
Furniture and Equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 89,489	91,036
Furniture and Equipment \| Minimum
Property Plant And Equipment [Line Items]
Useful life (years)	3 years
Furniture and Equipment \| Maximum
Property Plant And Equipment [Line Items]
Useful life (years)	10 years
Computer Systems and Equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 162,245	160,305
Computer Systems and Equipment \| Minimum
Property Plant And Equipment [Line Items]
Useful life (years)	3 years
Computer Systems and Equipment \| Maximum
Property Plant And Equipment [Line Items]
Useful life (years)	10 years
Construction Equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 6,842	8,920
Construction Equipment \| Minimum
Property Plant And Equipment [Line Items]
Useful life (years)	5 years
Construction Equipment \| Maximum
Property Plant And Equipment [Line Items]
Useful life (years)	7 years
Construction in Progress
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 10,242	$ 9,202

Property and Equipment, Net - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Property Plant And Equipment [Abstract]
Depreciation expense	$ 9.6	$ 9.5	$ 28.8	$ 28.9

Debt and Credit Facilities - Schedule of Debt (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Short-term debt	$ 0	$ 50,000
Convertible senior notes	400,000	400,000
Debt discount		(51,138)
Long-term debt issuance costs	(8,601)	(8,864)
Total long-term	591,399	539,998
Total Debt	591,399	589,998
Senior Notes
Debt Instrument [Line Items]
Short-term debt		50,000
Long-term debt	$ 200,000	$ 200,000

- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References + Details

Debt and Credit Facilities - Additional Information (Details)		1 Months Ended			3 Months Ended		6 Months Ended	9 Months Ended		12 Months Ended
	Jul. 01, 2014 USD ($)	Jul. 31, 2021 USD ($)	Jun. 30, 2021 USD ($) Extension	Aug. 31, 2020 USD ($) d $ / shares shares	Sep. 30, 2021 USD ($) $ / shares	Sep. 30, 2020 USD ($)	Jun. 30, 2021 USD ($)	Sep. 30, 2021 USD ($) d $ / shares shares	Sep. 30, 2020 USD ($)	Dec. 31, 2020 USD ($)	Mar. 31, 2021 USD ($)	Jan. 01, 2021 USD ($)	Aug. 10, 2020 USD ($)
Debt Instrument [Line Items]
Letters of credit outstanding amount					$ 221,200,000			$ 221,200,000		$ 193,100,000
Proceeds from issuance of warrants								0	$ 13,808,000
Deferred tax liabilities					23,554,000			23,554,000		12,285,000
Deferred tax assets					147,260,000			147,260,000		130,200,000
Level 2
Debt Instrument [Line Items]
Senior notes, fair value					223,100,000			223,100,000
Senior Notes
Debt Instrument [Line Items]
Debt instrument, outstanding amount					200,000,000			200,000,000		200,000,000
Senior Note, Series A
Debt Instrument [Line Items]
Senior note, amount paid		$ 50,000,000
Convertible Senior Notes
Debt Instrument [Line Items]
Interest rate				0.25%
Interest expense					700,000	$ 1,600,000		$ 2,200,000	1,600,000	4,400,000
Debt amount				$ 400,000,000.0
Exercise of option by initial purchasers aggregate principal amount				50,000,000.0
Proceeds from issuance and sale of debt				389,700,000
Transaction fees and other third-party offering expenses				$ 10,300,000
Debt instrument, payment terms								The Convertible Senior Notes accrue interest at a rate of 0.25% per annum, payable semi-annually on February 15 and August 15 of each year beginning on February 15, 2021
Debt instrument, frequency of periodic payment								semi-annually
Maturity Date				Aug. 15, 2025
Convertible note converted each amount					$ 1,000			$ 1,000
Convertible notes converted each into shares of common stock \| shares								22.2913
Debt Instrument, conversion price \| $ / shares					$ 44.86			$ 44.86
Threshold trading days \| d				20				51
Threshold consecutive trading days \| d				30
Conversion percentage of stock price trigger				130.00%
Number of business day period				5 days
Consecutive trading day period				5 days
Convertible principal amount				$ 1,000
Measurement period, percentage				98.00%
Percentage of principal amount to redeem convertible senior notes				100.00%
Percentage of convertible senior notes repurchased at cash				100.00%
Debt liability				$ 336,100,000
Debt instrument convertible notes additional paid in capital				$ 53,600,000
Convertible senior notes effective interest rate				3.25%
Net carrying value of notes					$ 400,000,000.0			$ 400,000,000.0		340,600,000
Bond hedge term								5 years
Number of shares issuable upon conversion \| shares				8,900,000
Cost of convertible note hedge transaction				$ 55,000,000.0
Number of common stock acquired by offsetting sale warrants. \| shares								8,900,000
Exercise price of warrants \| $ / shares					$ 66.46			$ 66.46
Proceeds from issuance of warrants								$ 13,800,000
Convertible Senior Notes \| ASU 2020-06
Debt Instrument [Line Items]
Reclassification of equity component of convertible senior notes to liabilities											$ 55,000,000.0
Reclassification of equity component of debt issuance costs to liabilities											$ 1,400,000
Carrying amount of convertible senior notes adjusted in retained earnings												$ 3,700,000
Convertible Note Hedge And Warrant Transaction
Debt Instrument [Line Items]
Purchase of bond hedges and sale of warrants				$ 41,200,000
Deferred tax liabilities					$ 16,200,000			16,200,000
Deferred tax assets					16,500,000			16,500,000
Convertible Note Hedge And Warrant Transaction \| ASU 2020-06
Debt Instrument [Line Items]
Deferred tax liability reversed					13,900,000			13,900,000
Additional deferred tax liability related to capitalized debt issuance costs					400,000			400,000
Adjustment to deferred tax asset through retained earnings					900,000			900,000
Private Placement
Debt Instrument [Line Items]
Debt issuance costs incurred	$ 1,100,000												$ 500,000
Debt amount	250,000,000.0
Private Placement \| Accrued Expenses and Other Current Liabilities
Debt Instrument [Line Items]
Interest payable					2,000,000.0			2,000,000.0		$ 5,500,000
Private Placement \| Senior Notes
Debt Instrument [Line Items]
Interest expense					2,700,000	3,100,000		8,900,000	9,300,000
Interest payments					$ 6,200,000	6,200,000		$ 12,400,000	12,400,000
Private Placement \| Senior Note, Series A
Debt Instrument [Line Items]
Debt amount	$ 50,000,000
Maturity Date	Jul. 15, 2021
Minimum \| Convertible Senior Notes
Debt Instrument [Line Items]
Debt Instrument, conversion price \| $ / shares				$ 44.86
Percentage of bond hedge and warrant transactions increased conversion price				35.00%
Maximum \| Convertible Senior Notes
Debt Instrument [Line Items]
Debt Instrument, conversion price \| $ / shares				$ 66.46
Percentage of bond hedge and warrant transactions increased conversion price				100.00%
Unsecured Revolving Credit Facility
Debt Instrument [Line Items]
Credit agreement date			Jun. 30, 2021
Revolving credit facility			$ 650,000,000				$ 650,000,000
Debt issuance costs incurred			1,900,000				1,900,000
Revolving credit facility			$ 550,000,000				$ 550,000,000
Credit agreement maturity period			5 years
Credit agreement number of extensions \| Extension			2
Interest rate					1.34%			1.34%		1.87%
Letters of credit outstanding amount					$ 45,000,000.0			$ 45,000,000.0		$ 44,900,000
Interest expense					100,000	$ 200,000		600,000	$ 900,000
Debt instrument, outstanding amount					$ 0			$ 0
Unsecured Revolving Credit Facility \| Base Rate \| Minimum
Debt Instrument [Line Items]
Margin interest rate							0.00%
Unsecured Revolving Credit Facility \| Base Rate \| Maximum
Debt Instrument [Line Items]
Margin interest rate							0.625%
Unsecured Revolving Credit Facility \| Euro Currency Rate \| Minimum
Debt Instrument [Line Items]
Margin interest rate							1.00%
Unsecured Revolving Credit Facility \| Euro Currency Rate \| Maximum
Debt Instrument [Line Items]
Margin interest rate							1.625%

Debt and Credit Facilities - Schedule of Aggregate Amount of Debt (Details) - Private Placement $ in Thousands	Jul. 01, 2014 USD ($)
Debt Instrument [Line Items]
Debt Amount	$ 250,000
Senior Note, Series A
Debt Instrument [Line Items]
Debt Amount	$ 50,000
Maturity Date	Jul. 15, 2021
Interest Rates	4.44%
Senior Note, Series B
Debt Instrument [Line Items]
Debt Amount	$ 100,000
Maturity Date	Jul. 15, 2024
Interest Rates	4.98%
Senior Note, Series C
Debt Instrument [Line Items]
Debt Amount	$ 60,000
Maturity Date	Jul. 15, 2026
Interest Rates	5.13%
Senior Note, Series D
Debt Instrument [Line Items]
Debt Amount	$ 40,000
Maturity Date	Jul. 15, 2029
Interest Rates	5.38%

Income Taxes - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Effective income tax rate	25.50%	25.60%	25.80%	26.40%
U.S. corporate tax rate	21.00%		21.00%
Deferred tax assets, valuation allowance	$ 32.0		$ 32.0
Liability for income taxes associated with uncertain tax positions	17.6		17.6		$ 16.4
Decrease in uncertain tax positions during the next twelve months	$ 0.2		$ 0.2

Contingencies - Additional Information (Details)		9 Months Ended
Contingencies - Additional Information (Details)	Mar. 01, 2017 USD ($)	Sep. 30, 2021 Claim
Legal Proceedings [Line Items]
Number of claims outstanding \| Claim		0
Minimum
Legal Proceedings [Line Items]
Loss contingency damages value \| $	$ 100,000,000.0

Retirement Benefit Plan - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Shares fully vested, Description			Shares allocated to a participant’s account are fully vested after three years of credited service, or in the event(s) of reaching age 65, death or disability while an active employee of the Company.
Shares fully vested after credited service			3 years
Common stock shares outstanding including ESOP	102,257,780		102,257,780		102,360,662
Company's stock held by ESOP	69,719,214		69,719,214		76,641,312
Direct Costs of Contracts and Selling, General and Administrative Expense
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
ESOP contribution expense	$ 14.8	$ 12.5	$ 41.3	$ 42.0

Investments in and Advances to Joint Ventures - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Schedule Of Equity Method Investments [Line Items]
Letters of credit outstanding amount	$ 221.2		$ 221.2		$ 193.1
Write-down on unconsolidated joint venture	5.5		10.6
Decrease in operating income	5.5		10.6
Decrease in net income net of tax	$ 4.1		$ 7.9
Decrease in earnings per share diluted	$ 0.04		$ 0.07
Unconsolidated Joint Ventures
Schedule Of Equity Method Investments [Line Items]
Net distributions from (contributions to) unconsolidated joint ventures	$ (7.3)	$ 11.2	$ (0.5)	$ 23.2
Consolidated Joint Ventures
Schedule Of Equity Method Investments [Line Items]
Letters of credit outstanding amount	$ 75.0		$ 75.0		$ 59.3

Investments in and Advances to Joint Ventures - Summary of Financial Information for Consolidated Joint Ventures (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Schedule Of Equity Method Investments [Line Items]
Current assets	$ 1,586,571		$ 1,586,571		$ 1,843,130
Total assets	3,823,933		3,823,933		3,937,704
Current liabilities	1,060,659		1,060,659		1,187,409
Total liabilities	1,970,057		1,970,057		2,076,287
Total joint venture equity	1,824,078		1,824,078		1,813,772
Revenue	956,050	$ 1,004,236	2,710,103	$ 2,954,688
Costs	734,652	788,769	2,084,062	2,307,725
Net income attributable to Parsons Corporation	19,358	40,658	35,099	76,930
Net income attributable to noncontrolling interests	7,411	5,862	17,711	15,086
Consolidated Joint Ventures
Schedule Of Equity Method Investments [Line Items]
Current assets	253,105		253,105		292,407
Noncurrent assets	1,856		1,856		2,990
Total assets	254,961		254,961		295,397
Current liabilities	194,543		194,543		201,270
Total liabilities	194,543		194,543		201,270
Total joint venture equity	60,418		60,418		$ 94,127
Revenue	101,816	117,344	296,685	335,511
Costs	86,726	105,223	260,129	304,308
Net income attributable to Parsons Corporation	15,090	12,121	36,556	31,203
Net income attributable to noncontrolling interests	$ 7,411	$ 5,862	$ 17,711	$ 15,086

Investments in and Advances to Joint Ventures - Summary of Financial Information for Unconsolidated Joint Ventures (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Schedule Of Equity Method Investments [Line Items]
Current assets	$ 1,586,571		$ 1,586,571		$ 1,843,130
Total assets	3,823,933		3,823,933		3,937,704
Current liabilities	1,060,659		1,060,659		1,187,409
Total liabilities	1,970,057		1,970,057		2,076,287
Total joint venture equity	1,824,078		1,824,078		1,813,772
Investments in and advances to unconsolidated joint ventures	102,677		102,677		68,975
Revenue	956,050	$ 1,004,236	2,710,103	$ 2,954,688
Costs	734,652	788,769	2,084,062	2,307,725
Net income attributable to Parsons Corporation	19,358	40,658	35,099	76,930
Equity in earnings of unconsolidated joint ventures	9,570	16,741	26,528	26,624
Unconsolidated Joint Ventures
Schedule Of Equity Method Investments [Line Items]
Current assets	1,103,345		1,103,345		774,646
Noncurrent assets	554,366		554,366		585,802
Total assets	1,657,711		1,657,711		1,360,448
Current liabilities	789,072		789,072		703,287
Noncurrent liabilities	562,523		562,523		517,697
Total liabilities	1,351,595		1,351,595		1,220,984
Total joint venture equity	306,116		306,116		139,464
Investments in and advances to unconsolidated joint ventures	102,677		102,677		$ 68,975
Revenue	728,461	594,640	1,701,262	1,286,087
Costs	697,493	551,624	1,604,538	1,202,315
Net income attributable to Parsons Corporation	30,968	43,016	96,724	83,772
Equity in earnings of unconsolidated joint ventures	$ 9,570	$ 16,741	$ 26,528	$ 26,624

Related Party Transactions - Additional Information (Details) - Unconsolidated joint ventures - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Related Party Transaction [Line Items]
Revenues	$ 37.1	$ 42.0	$ 119.5	$ 124.7
Reimbursable cost incurred	$ 29.0	$ 32.3	$ 90.9	$ 98.3

Related Party Transactions - Schedule of Consolidated Balance Sheet Related to Services Provided to Unconsolidated Joint Ventures (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Related Party Transaction [Line Items]
Contract assets	$ 569,294	$ 576,568
Contract liabilities	186,789	201,864
Unconsolidated Joint Ventures
Related Party Transaction [Line Items]
Accounts receivable	28,799	37,544
Contract assets	7,835	8,889
Contract liabilities	$ 9,188	$ 5,720

Earnings Per Share - Additional Information (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Aug. 31, 2021
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Shares of common stock repurchased					100,000,000.0
Stock repurchase program commencement date			Aug. 12, 2021
Stock repurchase program, remaining authorized repurchase amount	$ 91,300,000		$ 91,300,000
Stock-based Awards
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share	4,656	205	6,838	3,318

Earnings Per Share - Schedule of Weighted Average Number of Shares Used To Compute Basic and Diluted EPS (Details) - shares	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Earnings Per Share [Abstract]
Basic weighted average number of shares outstanding	102,478,095	100,736,862	102,463,511	100,700,498
Stock-based awards	751,807	378,486	637,686	321,070
Convertible senior notes	8,916,530	4,458,265	8,916,530	0
Diluted weighted average number of shares outstanding	112,146,432	105,573,613	112,017,727	101,021,568

Earnings Per Share - Net Income Available to Shareholders to Compute Basic and Diluted EPS (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Earnings Per Share [Abstract]
Net income attributable to Parsons Corporation	$ 19,358	$ 40,658	$ 35,099	$ 76,930
Convertible senior notes if-converted method interest adjustment	534	1,164	1,593
Diluted net income attributable to Parsons Corporation	$ 19,892	$ 41,822	$ 36,692	$ 76,930

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

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+ Details

Earnings Per Share - Schedule of Repurchase Program (Details)	9 Months Ended
	Sep. 30, 2021 $ / shares shares
Earnings Per Share [Abstract]
Total shares repurchased	245,000
Total shares retired	245,000
Average price paid per share \| $ / shares	$ 35.51

Segment Information - Additional Information (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2021 USD ($) segment	Sep. 30, 2020 USD ($)	Dec. 31, 2020 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments \| segment			2
Revenues	$ 956,050	$ 1,004,236	$ 2,710,103	$ 2,954,688
Property and equipment, net	105,895		105,895		$ 121,027
United States
Segment Reporting Information [Line Items]
Revenues	730,700	$ 774,000	2,000,000	$ 2,200,000
Property and equipment, net	$ 96,700		$ 96,700		$ 109,600

- Definition

+ References

+ Details

Segment Information - Summary of Business Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Segment Reporting Information [Line Items]
Total revenue	$ 956,050	$ 1,004,236	$ 2,710,103	$ 2,954,688
Federal Solution Segment
Segment Reporting Information [Line Items]
Total revenue	499,291	498,156	1,394,035	1,457,937
Critical Infrastructure
Segment Reporting Information [Line Items]
Total revenue	$ 456,759	$ 506,080	$ 1,316,068	$ 1,496,751

- Definition

+ References

+ Details

Segment Information - Summary of Adjusted EBITDA Business Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Adjusted EBITDA attributable to Parsons Corporation
Adjusted EBITDA attributable to Parsons Corporation	$ 76,852	$ 94,730	$ 200,808	$ 236,923
Adjusted EBITDA attributable to noncontrolling interests	7,540	6,071	18,010	15,535
Depreciation and amortization	(37,232)	(30,952)	(106,540)	(95,442)
Interest expense, net	(3,987)	(5,387)	(13,188)	(13,144)
Income tax expense	(9,165)	(16,017)	(18,378)	(32,992)
Equity-based compensation expense	(3,224)	991	(15,125)	(4,142)
Transaction-related costs	(2,537)	(2,411)	(9,269)	(11,937)
Restructuring expense	(357)	(365)	(507)	(1,475)
Other	(1,121)	(140)	(3,001)	(1,310)
Net income including noncontrolling interests	26,769	46,520	52,810	92,016
Net income attributable to noncontrolling interests	7,411	5,862	17,711	15,086
Net income attributable to Parsons Corporation	19,358	40,658	35,099	76,930
Federal Solution Segment
Adjusted EBITDA attributable to Parsons Corporation
Adjusted EBITDA attributable to Parsons Corporation	46,481	45,874	110,963	125,191
Critical Infrastructure
Adjusted EBITDA attributable to Parsons Corporation
Adjusted EBITDA attributable to Parsons Corporation	$ 30,371	$ 48,856	$ 89,845	$ 111,732

Segment Information - Summary of Revenues and Property and Equipment, Net by Geographic Area (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Segment Reporting Information [Line Items]
Revenues	$ 956,050	$ 1,004,236	$ 2,710,103	$ 2,954,688
Property and Equipment, Net	105,895		105,895		$ 121,027
North America
Segment Reporting Information [Line Items]
Revenues	804,122	831,367	2,245,515	2,429,357
Property and Equipment, Net	102,352		102,352		116,460
Middle East
Segment Reporting Information [Line Items]
Revenues	147,207	168,043	448,525	511,591
Property and Equipment, Net	3,543		3,543		$ 4,567
Rest of World
Segment Reporting Information [Line Items]
Revenues	$ 4,721	$ 4,826	$ 16,063	$ 13,740

- Definition

+ References

+ Details

Segment Information - Summary of Revenues by Business Lines (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Segment Reporting Information [Line Items]
Revenues	$ 956,050	$ 1,004,236	$ 2,710,103	$ 2,954,688
Federal Solution Segment
Segment Reporting Information [Line Items]
Revenues	499,291	498,156	1,394,035	1,457,937
Federal Solution Segment \| Defense And Intelligence
Segment Reporting Information [Line Items]
Revenues	343,151	333,289	962,642	953,755
Federal Solution Segment \| Engineered Systems
Segment Reporting Information [Line Items]
Revenues	156,140	164,867	431,393	504,182
Critical Infrastructure
Segment Reporting Information [Line Items]
Revenues	456,759	506,080	1,316,068	1,496,751
Critical Infrastructure \| Connected Communities
Segment Reporting Information [Line Items]
Revenues	91,902	116,366	263,106	316,626
Critical Infrastructure \| Mobility Solutions
Segment Reporting Information [Line Items]
Revenues	$ 364,857	$ 389,714	$ 1,052,962	$ 1,180,125

- Definition

+ References

+ Details

Contracts with Customers - Summary of Remaining Unsatisfied Performance Obligations Expect to Satisfy (Details) $ in Thousands	Sep. 30, 2021 USD ($)
Revenue Remaining Performance Obligation Expected Timing Of Satisfaction [Line Items]
Remaining unsatisfied performance obligations	$ 6,000,000
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2021-10-01
Revenue Remaining Performance Obligation Expected Timing Of Satisfaction [Line Items]
Remaining unsatisfied performance obligations	$ 2,871,543
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2022-01-01
Revenue Remaining Performance Obligation Expected Timing Of Satisfaction [Line Items]
Remaining unsatisfied performance obligations	$ 1,568,942
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2023-01-01
Revenue Remaining Performance Obligation Expected Timing Of Satisfaction [Line Items]
Remaining unsatisfied performance obligations	$ 1,513,725
Revenue, remaining performance obligation, expected timing of satisfaction, period
Federal Solution Segment \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2021-10-01
Revenue Remaining Performance Obligation Expected Timing Of Satisfaction [Line Items]
Remaining unsatisfied performance obligations	$ 1,418,783
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Federal Solution Segment \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2022-01-01
Revenue Remaining Performance Obligation Expected Timing Of Satisfaction [Line Items]
Remaining unsatisfied performance obligations	$ 787,273
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Federal Solution Segment \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2023-01-01
Revenue Remaining Performance Obligation Expected Timing Of Satisfaction [Line Items]
Remaining unsatisfied performance obligations	$ 491,797
Revenue, remaining performance obligation, expected timing of satisfaction, period
Critical Infrastructure \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2021-10-01
Revenue Remaining Performance Obligation Expected Timing Of Satisfaction [Line Items]
Remaining unsatisfied performance obligations	$ 1,452,760
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Critical Infrastructure \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2022-01-01
Revenue Remaining Performance Obligation Expected Timing Of Satisfaction [Line Items]
Remaining unsatisfied performance obligations	$ 781,669
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Critical Infrastructure \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2023-01-01
Revenue Remaining Performance Obligation Expected Timing Of Satisfaction [Line Items]
Remaining unsatisfied performance obligations	$ 1,021,928
Revenue, remaining performance obligation, expected timing of satisfaction, period