Revenue, Receivables and Contract Assets and Liabilities Accounts Receivable (Details) - USD ($) $ in Thousands	Nov. 28, 2020	Feb. 29, 2020
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total receivables	$ 174,739	$ 199,275
Less: allowance for credit losses	(1,862)	(2,469)
Net receivables	172,877	196,806
Trade accounts
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total receivables	122,959	141,126
Construction contracts
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total receivables	9,727	20,808
Contract retainage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total receivables	$ 42,053	$ 37,341