Revenue Recognition (Tables)

3 Months Ended

Mar. 31, 2019

Disaggregation Of Revenue [Abstract]

Disaggregation of Revenue

Disaggregation of Revenue

	Three Months Ended
	March 31, 2019					March 31, 2018
	Dollars		Percent			Dollars		Percent
Client Markets:
Energy, environment, and infrastructure	$	153,651		45	%	$	124,250		41	%
Health, education, and social programs		121,337		35	%		122,928		41	%
Safety and security		29,052		9	%		25,475		8	%
Consumer and financial		37,214		11	%		30,127		10	%
Total	$	341,254		100	%	$	302,780		100	%

	Three Months Ended
	March 31, 2019					March 31, 2018
	Dollars		Percent			Dollars		Percent
Client Type:
U.S. federal government	$	131,823		39	%	$	134,185		44	%
U.S. state and local government		65,522		19	%		31,313		10	%
International government		27,158		8	%		28,767		10	%
Total Government		224,503		66	%		194,265		64	%
Commercial		116,751		34	%		108,515		36	%
Total	$	341,254		100	%	$	302,780		100	%

	Three Months Ended
	March 31, 2019					March 31, 2018
	Dollars		Percent			Dollars		Percent
Contract Mix:
Fixed-price	$	133,534		39	%	$	122,328		40	%
Time-and-materials		156,347		46	%		124,342		41	%
Cost-based		51,373		15	%		56,110		19	%
Total	$	341,254		100	%	$	302,780		100	%

Schedule of Contract Balances and Changes in Contract Balances

Contract Balances:

	March 31, 2019			December 31, 2018			$ Change			% Change
Contract assets	$	151,805		$	126,688		$	25,117			19.8	%
Contract liabilities		(35,936	)		(33,494	)		(2,442	)		7.3	%
Net contract assets (liabilities)	$	115,869		$	93,194		$	22,675			24.3	%