Revenue Recognition (Tables)

3 Months Ended

Mar. 31, 2022

Revenue From Contract With Customer [Abstract]

Disaggregation of Revenue

Disaggregation of Revenue

Changes in the three months ended March 31, 2022 compared to the three months ended March 31, 2021 were driven primarily by an increase of $39.4 million and $6.2 million from U.S. federal government’s health, education, and social programs and energy, environment, and infrastructure client markets, respectively, $7.4 million and $0.5 million from U.S. state and local government’s health, education, and social programs and energy, environment, and infrastructure client markets, respectively, and $1.7 million from international government’s health, education, and social programs client market, offset by decreases of $11.1 million and $0.6 million from international government’s energy, environment, and infrastructure and safety and security client markets, respectively, $3.5 million, $2.6 million, and $1.2 million from commercial consumer and financial, energy, environment, and infrastructure, and health, education, and social programs client markets, respectively, and $1.2 million from U.S. federal government safety and security client market.

	Three Months Ended March 31,
	2022					2021
	Dollars		Percent			Dollars		Percent
Client Markets:
Energy, environment, and infrastructure	$	156,644		38	%	$	163,582		43	%
Health, education, and social programs		205,532		50	%		158,268		42	%
Safety and security		29,400		7	%		31,198		8	%
Consumer and financial		21,892		5	%		25,430		7	%
Total	$	413,468		100	%	$	378,478		100	%

	Three Months Ended March 31,
	2022					2021
	Dollars		Percent			Dollars		Percent
Client Type:
U.S. federal government	$	220,343		53	%	$	175,985		46	%
U.S. state and local government		64,833		16	%		56,878		15	%
International government		26,720		6	%		36,746		10	%
Total Government		311,896		75	%		269,609		71	%
Commercial		101,572		25	%		108,869		29	%
Total	$	413,468		100	%	$	378,478		100	%

	Three Months Ended March 31,
	2022					2021
	Dollars		Percent			Dollars		Percent
Contract Mix:
Time-and-materials	$	165,084		40	%	$	159,836		42	%
Fixed price		183,896		44	%		147,469		39	%
Cost-based		64,488		16	%		71,173		19	%
Total	$	413,468		100	%	$	378,478		100	%

Schedule of Contract Balances and Changes in Contract Balances

Contract Balances:

Contract assets consist primarily of unbilled amounts resulting from long-term contracts when revenue recognized exceeds the amount billed often due to billing schedule timing. Contract liabilities result from advance payments received on a contract or from billings in excess of revenue recognized on long-term contracts due to billing schedule timing.

The following table summarizes the contract balances as of March 31, 2022 and December 31, 2021:

	March 31, 2022			December 31, 2021			$ Change		% Change
Contract assets	$	189,147		$	137,867		$	51,280		37.2	%
Contract liabilities		(31,491	)		(39,665	)		8,174		(20.6	%)
Net contract assets (liabilities)	$	157,656		$	98,202		$	59,454		60.5	%