Revenue Recognition (Tables)

12 Months Ended

Dec. 31, 2024

Revenue from Contract with Customer [Abstract]

Disaggregation of Revenue

The Company’s revenue by client markets, type, and contract mix are in the following tables. Certain immaterial revenue amounts in the prior years have been reclassified due to minor adjustments and reclassification.

	Year ended December 31,
	2024		2023		2022
Client Markets:
Energy, environment, infrastructure, and disaster recovery	$	929,711	$	805,942	$	714,628
Health and social programs		764,477		814,789		704,465
Security and other civilian & commercial		325,599		342,507		360,871
Total	$	2,019,787	$	1,963,238	$	1,779,964

	Year ended December 31,
	2024		2023		2022
Client Type:
U.S. federal government	$	1,087,349	$	1,084,047	$	980,746
U.S. state and local government		316,083		309,516		259,764
International government		110,798		103,446		103,609
Total Government		1,514,230		1,497,009		1,344,119
Commercial		505,557		466,229		435,845
Total	$	2,019,787	$	1,963,238	$	1,779,964

	Year ended December 31,
	2024		2023		2022
Contract Mix:
Time-and-materials	$	855,538	$	811,911	$	713,693
Fixed-price		932,351		886,200		802,568
Cost-based		231,898		265,127		263,703
Total	$	2,019,787	$	1,963,238	$	1,779,964

Schedule of Contract Assets and Liabilities and Changes in Contract Balances

Contract Assets and Liabilities:

Contract assets consist of unbilled receivables on contracts where revenue recognized exceeds the amount billed. Contract liabilities result from advance payments received on a contract or from billings in excess of revenue recognized on long-term contracts.

The following table summarizes the contract balances as of December 31, 2024 and December 31, 2023:

	December 31, 2024			December 31, 2023			Change
Contract assets	$	188,941		$	201,832		$	(12,891	)
Contract liabilities		(24,580	)		(21,997	)		(2,583	)
Net contract assets (liabilities)	$	164,361		$	179,835		$	(15,474	)

The net contract assets (liabilities) as of December 31, 2024 decreased by $15.5 million as compared to December 31, 2023, primarily due to the timing difference between the performance of services and billings to and payments from customers. There were no material changes to contract balances due to impairments or credit losses during the period. During the years ended December 31, 2024 and 2023, the Company recognized $17.6 million and $17.8 million in revenue related to the contract liabilities balance at December 31, 2023 and 2022, respectively.

Unfulfilled