Accounts Receivable, Contract Assets, and Contract Liabilities - Change in Allowance for Doubtful Accounts (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 31, 2021	Jul. 25, 2020	Jul. 31, 2021	Jul. 25, 2020
Accounts, Notes, Loans and Financing Receivable [Line Items]
Cumulative effect from implementation of ASU 2016-13	$ 4,237	$ 5,166	$ 1,676	$ 4,582
Provision for bad debt	78	119	2,901	236
Amounts charged against the allowance	(2,788)	(3,680)	(3,050)	(3,684)
Allowance for doubtful accounts at end of period	1,527	1,605	1,527	1,605
Cumulative effect from implementation of ASU 2016-13
Accounts, Notes, Loans and Financing Receivable [Line Items]
Cumulative effect from implementation of ASU 2016-13	$ 0	$ 0	$ 0	$ 471