Contracts with Customers (Tables)

6 Months Ended

Jun. 30, 2021

Revenue From Contract With Customer [Abstract]

Summary of 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				Six Months Ended
	June 30, 2021		June 30, 2020		June 30, 2021		June 30, 2020
Fixed-Price	$	233,231	$	311,368	$	463,173	$	619,676
Time-and-Materials		253,365		259,381		493,030		511,820
Cost-Plus		392,760		408,710		797,850		818,956
Total	$	879,356	$	979,459	$	1,754,053	$	1,950,452

Summary of Contract Assets and Contract Liabilities

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

	June 30, 2021		December 31, 2020		$ change			% change
Contract assets	$	568,239	$	576,568	$	(8,329	)		-1.4	%
Contract liabilities		196,547		201,864		(5,317	)		-2.6	%
Net contract assets (liabilities) (1)	$	371,692	$	374,704	$	(3,012	)		-0.8	%

(1) Total contract retentions included in net contract assets (liabilities) were $94.7 million as of June 30, 2021, of which $50.8 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 June 30, 2021 and December 31, 2020 include $103.4 million and $116.6 million, respectively, related to unapproved change orders, claims, and requests for equitable adjustment. For the three and six months ended June 30, 2021 and June 30, 2020, there were no material losses recognized related to the collectability of claims, unapproved change orders, and requests for equitable adjustment.

Summary of Changes in Contract Assets and Contract Liabilities

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

	June 30, 2021		December 31, 2020
Acquired contract assets	$	-	$	8,350
Acquired contract liabilities		-		300

Summary of Changes in Revenue

 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					Six Months Ended
	June 30, 2021			June 30, 2020		June 30, 2021			June 30, 2020
Revenue impact, net	$	(20,827	)	$	8,983	$	(20,827	)	$	8,983

Summary of Accounts Receivable, Net

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

	2021			2020
Billed	$	458,686		$	512,357
Unbilled		183,293			190,222
Total accounts receivable, gross		641,979			702,579
Allowance for doubtful accounts		(3,999	)		(4,001	)
Total accounts receivable, net	$	637,980		$	698,578

Summary of Remaining Unsatisfied Performance Obligations Expect to Satisfy

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

Period RUPO Will Be Satisfied	Within One Year		Within One to Two Years		Thereafter
Federal Solutions	$	1,071,149	$	461,928	$	355,680
Critical Infrastructure		1,581,878		760,048		861,020
Total	$	2,653,027	$	1,221,976	$	1,216,700