Pension and Savings Plans - Plan's Funded Status and Amounts Recognized in Company's Consolidated Balance Sheets (Detail) - USD ($) $ in Thousands	12 Months Ended
	Aug. 27, 2016	Aug. 29, 2015	Aug. 30, 2014
Change in Projected Benefit Obligation:
Projected benefit obligation at beginning of year	$ 296,123	$ 300,966
Interest cost	11,272	12,338	$ 13,070
Actuarial (gains) losses	39,842	(1,056)
Benefits paid	(18,726)	(16,125)
Benefit obligations at end of year	328,511	296,123	300,966
Change in Plan Assets:
Fair value of plan assets at beginning of year	238,755	243,407
Actual return on plan assets	16,636	(5,604)
Employer contributions	52,721	17,077	16,900
Benefits paid	(18,726)	(16,125)
Fair value of plan assets at end of year	289,386	238,755	$ 243,407
Amount Recognized in the Statement of Financial Position:
Current liabilities	(276)	(253)
Long-term liabilities	(38,849)	(57,115)
Net amount recognized	(39,125)	(57,368)
Amount Recognized in Accumulated Other Comprehensive Loss and not yet reflected in Net Periodic Benefit Cost:
Net actuarial loss	(145,948)	(116,735)
Accumulated other comprehensive loss	(145,948)	(116,735)
Amount Recognized in Accumulated Other Comprehensive Loss and not yet reflected in Net Periodic Benefit Cost and expected to be amortized in next year's Net Periodic Benefit Cost:
Net actuarial loss	(13,874)	(10,506)
Amount recognized	$ (13,874)	$ (10,506)