Revenue, Receivables and Contract Assets and Liabilities Accounts Receivable (Details) - USD ($) $ in Thousands	Aug. 28, 2021	Feb. 27, 2021	Feb. 29, 2020
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total receivables	$ 162,961	$ 177,864
Accounts Receivable, Allowance for Credit Loss	2,103	1,947	$ 2,469
Net receivables	160,858	175,917
Trade accounts
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total receivables	123,658	120,534
Construction contracts
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total receivables	5,584	12,163
Contract retainage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total receivables	$ 33,719	$ 45,167