Subsequent Events	9 Months Ended
	Sep. 26, 2021
Subsequent Events [Abstract]
Subsequent Events	Subsequent EventsOn October 25, 2021, PAE Incorporated (the “Company”) entered into an Agreement and Plan of Merger (the “Amentum Merger Agreement”) with Amentum Government Services Holdings LLC (“Parent”) and Pinnacle Virginia Merger Sub Inc., an indirect wholly-owned subsidiary of Parent (“Merger Sub”), providing for the merger of Merger Sub with and into the Company (the “Merger”), with the Company continuing as the surviving company of the Merger and an indirect wholly-owned subsidiary of Parent (the “Surviving Corporation”). Pursuant to the terms and conditions set forth in the Amentum Merger Agreement, at the effective time of the merger (the “Effective Time”), each share of Class A common stock par value $0.0001 of the Company outstanding as of immediately prior to the Effective Time will automatically be canceled, extinguished and converted into the right to receive an amount equal to $10.05 in cash per share, net any applicable withholding and without interest. The Amentum Merger Agreement prohibits the Company and its advisors and representatives from soliciting, encouraging, providing information or entering into discussions concerning proposals relating to alternative business combination transactions, subject to certain limited exceptions. However, during the period beginning on October 25, 2021 and continuing until November 29, 2021 (the “Go-Shop Period”), the Company is permitted to take such actions with respect to certain competing acquisition proposals. At the end of the Go-Shop Period, the Company will cease such activities and will be subject to customary “no shop” restrictions on its ability to solicit third party proposals relating to competing acquisition proposals or to provide information to and engage in discussions with certain third parties. In the event the Amentum Merger Agreement is terminated by the Company in certain circumstances, the Company may be required to pay a termination fee of either $15.0 million or $30.0 million (including in order to enter into a definitive agreement with respect to a Company Superior Proposal, as defined in the Amentum Merger Agreement) to the Parent. The termination rights of the parties to the Amentum Merger Agreement are subject to certain notice, cure and other rights.