Summary of Selected Quarterly Financial Data (Unaudited) (Details) - USD ($) $ in Thousands	3 Months Ended																12 Months Ended
	Dec. 31, 2017		Sep. 30, 2017		Jun. 30, 2017		Mar. 31, 2017		Dec. 31, 2016		Sep. 30, 2016		Jun. 30, 2016		Mar. 31, 2016		Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Summary of Selected Quarterly Financial Data (Unaudited) [Abstract]
Revenue	$ 35,278		$ 28,243		$ 21,096		$ 23,110		$ 26,052		$ 54,940		$ 26,798		$ 27,078		$ 107,727	$ 134,868	$ 120,634
Gross profit	15,470		9,262		7,391		8,443		8,874		14,538		9,452		10,582
Loss before income taxes and non-controlling interest	1,308		(1,755)		(3,011)		(2,807)		(3,366)		1,503		(1,323)		(149)		(6,265)	(3,335)	(9,237)
Net loss attributable to Telos Corporation	$ 3,699	[1],[2]	$ (3,044)	[1],[2]	$ (3,389)	[1],[2]	$ (3,099)	[1],[2]	$ (4,305)	[2]	$ (91)	[2]	$ (1,912)	[2]	$ (867)	[2]	$ (5,833)	$ (7,175)	$ (15,940)

[1] A tax benefit was recorded due primarily to the remeasurement of our deferred tax assets and liabilities, and the adjustment of valuation allowance related to our hanging credit deferred tax liability in the fourth quarter of 2017, as a result of the Tax Act enacted in December 2017.

[2] Changes in net income are the result of several factors, including seasonality of the government year-end buying season, as well as the nature and timing of other deliverables.