Summary of Significant Accounting Policies - Schedule of Impacts of New Accounting Pronouncements on Consolidated Balance Sheet (Details) - USD ($) $ in Thousands	Aug. 31, 2019	Aug. 26, 2018	Aug. 25, 2018	Aug. 26, 2017	Aug. 27, 2016
Assets
Prepaid expenses and other current assets	$ 35,699	$ 33,288	$ 21,899
Total current assets	913,791	796,189	784,800
Other assets	84,674	74,664	30,259
Total assets	2,047,320	1,899,180	1,843,386	$ 1,819,128
Liabilities and shareholders’ equity
Accrued and deferred income taxes	99,172	88,497	74,070
Total liabilities	406,090	392,846	378,419
Retained earnings	1,588,075	1,446,606	1,405,239
Total shareholders’ equity	1,641,230	1,506,334	1,464,967	$ 1,453,192	$ 1,364,781
Total liabilities and shareholders’ equity	2,047,320	$ 1,899,180	1,843,386
Under Historical Guidance
Assets
Prepaid expenses and other current assets	23,285
Total current assets	901,377
Other assets	34,339
Total assets	1,984,571
Liabilities and shareholders’ equity
Accrued and deferred income taxes	83,114
Total liabilities	390,032
Retained earnings	1,541,384
Total shareholders’ equity	1,594,539
Total liabilities and shareholders’ equity	1,984,571
Accounting Standards Update 2014-09
Assets
Prepaid expenses and other current assets			11,389
Total current assets			11,389
Other assets			44,405
Total assets			55,794
Liabilities and shareholders’ equity
Accrued and deferred income taxes			14,427
Total liabilities			14,427
Retained earnings			41,367
Total shareholders’ equity			41,367
Total liabilities and shareholders’ equity			$ 55,794
Accounting Standards Update 2014-09 | Capitalization of Contract Costs and Impact of Adopting New Revenue Standard
Assets
Prepaid expenses and other current assets	12,414
Total current assets	12,414
Other assets	50,335
Total assets	62,749
Liabilities and shareholders’ equity
Accrued and deferred income taxes	16,058
Total liabilities	16,058
Retained earnings	46,691
Total shareholders’ equity	46,691
Total liabilities and shareholders’ equity	$ 62,749