Segment Reporting - Revenues and Income Before Income Taxes by Geographic Area (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Aug. 31, 2019	May 25, 2019	Feb. 23, 2019	Nov. 24, 2018	Aug. 25, 2018	May 26, 2018	Feb. 24, 2018	Nov. 25, 2017	Aug. 31, 2019	Aug. 25, 2018	Aug. 26, 2017
Revenues From External Customers And Long Lived Assets [Line Items]
Revenues	$ 479,621	$ 453,720	$ 437,485	$ 438,550	$ 434,063	$ 427,384	$ 419,264	$ 415,778	$ 1,809,376	$ 1,696,489	$ 1,590,958
Income before income taxes									237,924	187,246	115,123
United States
Revenues From External Customers And Long Lived Assets [Line Items]
Revenues									1,683,321	1,559,780	1,472,432
Income before income taxes									236,843	184,605	109,741
Europe, Canada, Mexico and Nicaragua
Revenues From External Customers And Long Lived Assets [Line Items]
Income before income taxes									1,081	2,641	5,382
Europe and Canada
Revenues From External Customers And Long Lived Assets [Line Items]
Revenues									$ 126,055	$ 136,709	$ 118,526