Revenue Recognition (Tables)

6 Months Ended

Jun. 30, 2018

Disaggregation Of Revenue [Abstract]

Disaggregation of Revenue

Disaggregation of Revenue

	June 30, 2018
	Three Months Ended		Six Months Ended
Client Markets:
Energy, environment, and infrastructure	$	132,563	$	256,318
Health, education, and social programs		131,624		255,189
Safety and security		27,491		52,927
Consumer and financial		32,637		62,661
Total	$	324,315	$	627,095

	June 30, 2018
	Three Months Ended		Six Months Ended
Client Type:
U.S. federal government	$	138,875	$	272,597
U.S. state and local government		35,267		67,172
International government		34,508		63,245
Total Government		208,650		403,014
Commercial		115,665		224,081
Total	$	324,315	$	627,095

	June 30, 2018
	Three Months Ended		Six Months Ended
Contract Mix:
Fixed-price	$	136,178	$	258,825
Time-and-materials		128,243		252,268
Cost-based		59,894		116,002
Total	$	324,315	$	627,095

Schedule of Contract Balances and Changes in Contract Balances

Contract Balances:

	June 30, 2018			At date of adoption			Change
Contract asset	$	130,241		$	123,197		$	7,044
Contract liabilities		(25,886	)		(38,571	)		12,685
Net contract assets (liabilities)	$	104,355		$	84,626		$	19,729