Revenue Recognition (Tables)

9 Months Ended

Sep. 30, 2018

Disaggregation Of Revenue [Abstract]

Disaggregation of Revenue

Disaggregation of Revenue

	September 30, 2018
	Three Months Ended		Nine Months Ended
Client Markets:
Energy, environment, and infrastructure	$	147,840	$	404,476
Health, education, and social programs		126,347		381,287
Safety and security		29,446		82,412
Consumer and financial		29,335		91,888
Total	$	332,968	$	960,063

	September 30, 2018
	Three Months Ended		Nine Months Ended
Client Type:
U.S. federal government	$	139,875	$	412,403
U.S. state and local government		55,828		122,958
International government		26,559		89,968
Total Government		222,262		625,329
Commercial		110,706		334,734
Total	$	332,968	$	960,063

	September 30, 2018
	Three Months Ended		Nine Months Ended
Contract Mix:
Fixed-price	$	126,332	$	384,870
Time-and-materials		146,472		399,023
Cost-based		60,164		176,170
Total	$	332,968	$	960,063

Schedule of Contract Balances and Changes in Contract Balances

Contract Balances:

	September 30, 2018			At date of adoption			Change
Contract assets	$	143,161		$	123,197		$	19,964
Contract liabilities		(26,489	)		(38,571	)		12,082
Net contract assets (liabilities)	$	116,672		$	84,626		$	32,046