Other Accrued Liabilities (Details) - USD ($) $ in Thousands	Jan. 27, 2018	Jul. 29, 2017	Jul. 30, 2016
Payables and Accruals [Abstract]
Accrued payroll and related taxes	$ 23,010	$ 24,554	$ 23,908
Accrued employee benefit and incentive plan costs	16,097	42,135	40,943
Accrued construction costs	24,582	29,942	41,123
Other current liabilities	15,968	16,972	16,328
Total other accrued liabilities	$ 79,657	$ 113,603	$ 122,302