Unaudited Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Income Statement [Abstract]
Revenue	$ 511,800	$ 570,459	$ 1,570,011	$ 1,548,601
Costs and expenses
Cost of revenue	435,594	486,382	1,341,826	1,316,482
Selling, general and administrative expenses	39,337	49,578	129,780	159,493
Total costs and expenses	474,931	535,960	1,471,606	1,475,975
Operating income	36,869	34,499	98,405	72,626
Interest expense, net	50,855	31,261	109,358	80,589
Other income (expenses), net		15	(82)	44
Income (loss) before income taxes	(13,986)	3,253	(11,035)	(7,919)
Provision (benefit) for income taxes	1,348	(1,661)	2,370	(15,662)
Net income (loss)	(15,334)	4,914	(13,405)	7,743
Less: Net income attributable to non-controlling interest	1,423	1,264	4,088	4,364
Net income (loss) attributable to Engility	$ (16,757)	$ 3,650	$ (17,493)	$ 3,379
Earnings (loss) per share attributable to Engility
Basic	$ (0.46)	$ 0.10	$ (0.48)	$ 0.10
Diluted	$ (0.46)	$ 0.10	$ (0.48)	$ 0.10
Weighted average number of shares outstanding
Basic	36,735	36,623	36,726	32,527
Diluted	36,735	37,136	36,726	33,065