Consolidated Statements of Stockholders Equity - USD ($) $ in Thousands	Total	Cumulative Effect, Period of Adoption, Adjustment	Previously Reported	Restatement Adjustment	Total PAE Incorporated Stockholders’ Equity	Total PAE Incorporated Stockholders’ Equity Cumulative Effect, Period of Adoption, Adjustment	Total PAE Incorporated Stockholders’ Equity Previously Reported	Common Stock	Common Stock Previously Reported	Common Stock Restatement Adjustment	Additional Paid-in Capital	Additional Paid-in Capital Previously Reported	Additional Paid-in Capital Restatement Adjustment	Accumulated Deficit	Accumulated Deficit Cumulative Effect, Period of Adoption, Adjustment	Accumulated Deficit Previously Reported	Accumulated Other Comprehensive (Loss) / Income	Accumulated Other Comprehensive (Loss) / Income Previously Reported	Noncontrolling Interests	Noncontrolling Interests Cumulative Effect, Period of Adoption, Adjustment	Noncontrolling Interests Previously Reported
Beginning balance at Dec. 31, 2017	$ 66,439	$ (1,195)			$ 37,734	$ 145		$ 3			$ 101,742			$ (61,248)	$ 145		$ (2,763)		$ 28,705	$ (1,340)
Beginning balance (in shares) at Dec. 31, 2017								282,047,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income	(31,578)				(34,459)									(34,459)					2,881
Other comprehensive income, net	625				625												625
Distributions to venture partners and other	(2,806)																		(2,806)
Ending balance at Dec. 31, 2018	31,485		$ 31,485	$ 0	4,045		$ 4,045	$ 2	$ 3	$ (1)	101,743	$ 101,742	$ 1	(95,562)		$ (95,562)	(2,138)	$ (2,138)	27,440		$ 27,440
Ending balance (in shares) at Dec. 31, 2018								21,127,823,000	282,047,000	20,845,776,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income	(50,061)				(49,809)									(49,809)					(252)
Other comprehensive income, net	2,004				2,004												2,004
Distributions to venture partners and other	(742)																		(742)
Equity contributions from venture partners	5,405																		5,405
Ending balance at Dec. 31, 2019	$ (11,909)				(43,760)			$ 2			101,743			(145,371)			(134)		31,851
Ending balance (in shares) at Dec. 31, 2019	21,127,823							21,127,823,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income	$ 26,150		(4,777)	30,927
Other comprehensive income, net	$ (695)		(695)	0
Ending balance (in shares) at Mar. 29, 2020	92,040,654
Beginning balance at Dec. 31, 2019	$ (11,909)				(43,760)			$ 2			101,743			(145,371)			(134)		31,851
Beginning balance (in shares) at Dec. 31, 2019	21,127,823							21,127,823,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income	$ 23,469		12,009	11,460
Other comprehensive income, net	$ (493)		(493)	0
Ending balance (in shares) at Jun. 28, 2020	92,040,654
Beginning balance at Dec. 31, 2019	$ (11,909)				(43,760)			$ 2			101,743			(145,371)			(134)		31,851
Beginning balance (in shares) at Dec. 31, 2019	21,127,823							21,127,823,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income	$ 39,199		22,739	16,460
Other comprehensive income, net	$ 287		287	0
Ending balance (in shares) at Sep. 27, 2020	92,040,654
Beginning balance at Dec. 31, 2019	$ (11,909)				(43,760)			$ 2			101,743			(145,371)			(134)		31,851
Beginning balance (in shares) at Dec. 31, 2019	21,127,823							21,127,823,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income	$ 27,286		13,826	13,460	28,750														(1,464)
Other comprehensive income, net	2,010		2,010	0	2,010												2,010
Distributions to venture partners and other	(291)																		(291)
Equity contributions from venture partners	2,140																		2,140
Private placement	212,910				212,910			$ 2			212,908
Private placement (in shares)								23,913,044,000
Equity infusion from Gores	307,941				307,941			$ 5			307,936
Equity infusion from Gores (in shares)								46,999,787,000
Payment to Shay Stockholders	(446,845)				(446,845)						(446,845)
Stock-based compensation	12,943				12,943						12,943
Ending balance at Dec. 31, 2020	$ 106,185				$ 73,949			$ 9			$ 188,685			$ (116,621)			$ 1,876		$ 32,236
Ending balance (in shares) at Dec. 31, 2020	92,040,654							92,040,654,000
Beginning balance (in shares) at Mar. 29, 2020	92,040,654
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income	$ (2,681)		16,786	(19,467)
Other comprehensive income, net	$ 201		201	0
Ending balance (in shares) at Jun. 28, 2020	92,040,654
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income	$ 15,731		10,731	5,000
Other comprehensive income, net	$ 781		$ 781	$ 0
Ending balance (in shares) at Sep. 27, 2020	92,040,654