Quarterly Financial Data (Unaudited) - Schedule of Quarterly Financial Information (Details) - USD ($) $ / shares in Units, shares in Thousands, $ 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
Condensed Income Statements, Captions [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	60,870	61,700	63,395	51,959	42,853	47,792	43,568	53,033	237,924	187,246	115,123
Provision (benefit) for income taxes	14,882	14,480	15,789	13,639	7,901	11,433	(14,810)	18,827	58,790	23,351	44,927
Net income	$ 45,988	$ 47,220	$ 47,606	$ 38,320	$ 34,952	$ 36,359	$ 58,378	$ 34,206	$ 179,134	$ 163,895	$ 70,196
Income per share—diluted
Common stock (in dollars per share)									$ 9.33	$ 8.21	$ 3.44
Income allocated to—Basic:
Common stock									$ 179,134	$ 163,895	$ 70,196
Income allocated to—diluted
Common Stock									$ 179,134	$ 163,895	$ 69,837
Weighted average number of shares outstanding—Basic:
Common stock (in shares)									19,082	19,811	20,284
Weighted average number of shares outstanding—diluted
Common stock (in shares)									19,196	19,963	20,276
Common Stock
Income per share—Basic:
Common stock (in dollars per share)	$ 2.52	$ 2.58	$ 2.59	$ 2.08	$ 1.90	$ 1.94	$ 3.02	$ 1.77	$ 9.77	$ 8.66	$ 3.63
Income per share—diluted
Common stock (in dollars per share)	$ 2.40	$ 2.46	$ 2.48	$ 1.99	$ 1.81	$ 1.85	$ 2.85	$ 1.67
Income allocated to—Basic:
Common stock	$ 38,619	$ 39,563	$ 39,923	$ 32,137	$ 29,312	$ 30,034	$ 46,744	$ 27,384	$ 150,247	$ 133,802	$ 55,903
Income allocated to—diluted
Common Stock	$ 45,988	$ 47,220	$ 47,606	$ 38,320	$ 34,952	$ 36,359	$ 58,378	$ 34,206
Weighted average number of shares outstanding—Basic:
Common stock (in shares)	15,340	15,341	15,428	15,432	15,429	15,446	15,481	15,462	15,385	15,454	15,382
Weighted average number of shares outstanding—diluted
Common stock (in shares)	19,159	19,168	19,232	19,302	19,335	19,687	20,463	20,434
Class B Common Stock
Income per share—Basic:
Common stock (in dollars per share)	$ 2.01	$ 2.06	$ 2.07	$ 1.67	$ 1.52	$ 1.55	$ 2.42	$ 1.42	$ 7.81	$ 6.91	$ 2.91
Income allocated to—Basic:
Common stock	$ 7,369	$ 7,657	$ 7,683	$ 6,183	$ 5,640	$ 6,325	$ 11,634	$ 6,822	$ 28,887	$ 30,093	$ 13,915
Weighted average number of shares outstanding—Basic:
Common stock (in shares)	3,659	3,710	3,710	3,710	3,711	4,087	4,816	4,816	3,697	4,357	4,786