Net Income Per Share - Schedule of Computation of Basic Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Feb. 24, 2018	Feb. 25, 2017	Feb. 24, 2018	Feb. 25, 2017
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Net income available to shareholders	$ 58,378	$ 22,516	$ 92,584	$ 50,730
Allocation of net income for Basic:
Common Stock	$ 58,378	$ 22,516	$ 92,584	$ 50,730
Weighted average number of shares for Basic:
Common Stock (in shares)	20,297	20,290	20,287	20,281
Common Stock
Allocation of net income for Basic:
Common Stock	$ 46,744	$ 17,836	$ 74,126	$ 40,178
Weighted average number of shares for Basic:
Common Stock (in shares)	15,481	15,305	15,471	15,295
Earnings per share for Basic:
Common Stock (in dollars per share)	$ 3.02	$ 1.17	$ 4.79	$ 2.63
Class B Common Stock
Allocation of net income for Basic:
Common Stock	$ 11,634	$ 4,518	$ 18,458	$ 10,184
Weighted average number of shares for Basic:
Common Stock (in shares)	4,816	4,846	4,816	4,846
Earnings per share for Basic:
Common Stock (in dollars per share)	$ 2.42	$ 0.93	$ 3.83	$ 2.10
Unvested participating shares
Allocation of net income for Basic:
Common Stock	$ 0	$ 162	$ 0	$ 368
Weighted average number of shares for Basic:
Common Stock (in shares)	0	139	0	140