Summary of Significant Accounting Policies - Schedule of Computation of Diluted Income Per Share (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
Earnings Per Share Diluted [Line Items]
Common Stock									$ 179,134	$ 163,895	$ 70,196
Common Stock (in shares)									19,082	19,811	20,284
Add: Undistributed earnings allocated to unvested participating shares										$ 0	$ 362
Less: Undistributed earnings reallocated to unvested participating shares										0	(343)
Common Stock									$ 179,134	$ 163,895	$ 69,837
Common stock (in shares)									19,196	19,963	20,276
Diluted EPS – Common Stock (in dollars per share)									$ 9.33	$ 8.21	$ 3.44
Common Stock
Earnings Per Share Diluted [Line Items]
Common Stock	$ 38,619	$ 39,563	$ 39,923	$ 32,137	$ 29,312	$ 30,034	$ 46,744	$ 27,384	$ 150,247	$ 133,802	$ 55,903
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
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
Add: effect of dilutive potential common shares										$ 0	$ 0
Common Stock	$ 45,988	$ 47,220	$ 47,606	$ 38,320	$ 34,952	$ 36,359	$ 58,378	$ 34,206
Add: effect of dilutive potential common shares (in shares)									114	152	108
Common stock (in shares)	19,159	19,168	19,232	19,302	19,335	19,687	20,463	20,434
Diluted EPS – Common Stock (in dollars per share)	$ 2.40	$ 2.46	$ 2.48	$ 1.99	$ 1.81	$ 1.85	$ 2.85	$ 1.67
Class B Common Stock
Earnings Per Share Diluted [Line Items]
Common Stock	$ 7,369	$ 7,657	$ 7,683	$ 6,183	$ 5,640	$ 6,325	$ 11,634	$ 6,822	$ 28,887	$ 30,093	$ 13,915
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
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