Accounts Receivable, Net - Schedule of Accounts Receivable, Net (Details) - USD ($) $ in Thousands	Jul. 02, 2021	Dec. 31, 2020
Accounts, Notes, Loans and Financing Receivable [Line Items]
Less allowance for doubtful accounts	$ (1,594)	$ (2,008)
Accounts receivable, net	99,361	153,806
Accounts Receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable	22,187	19,945
U.S. Government contracts | Billed | Accounts Receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable	21,928	18,854
U.S. Government contracts | Not billed | Accounts Receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable	727	1,080
Commercial and other government contracts | Billed | Accounts Receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable	48,731	111,794
Commercial and other government contracts | Not billed | Accounts Receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable	$ 7,382	$ 4,141