Accounts Receivable, Net - Schedule of Accounts Receivable, Net (Details) - USD ($) $ in Thousands	Apr. 02, 2021	Dec. 31, 2020
Accounts, Notes, Loans and Financing Receivable [Line Items]
Less allowance for doubtful accounts	$ (1,605)	$ (2,008)
Accounts receivable, net	102,328	153,806
Accounts Receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable	22,353	19,945
U.S. Government contracts | Billed | Accounts Receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable	18,106	18,854
U.S. Government contracts | Not billed | Accounts Receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable	905	1,080
Commercial and other government contracts | Billed | Accounts Receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable	58,428	111,794
Commercial and other government contracts | Not billed | Accounts Receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable	$ 4,141	$ 4,141