Pension and Savings Plans - Plan's Funded Status and Amounts Recognized in Company's Consolidated Balance Sheets (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Aug. 31, 2013	Aug. 25, 2012	Aug. 27, 2011
Change in Projected Benefit Obligation:
Projected benefit obligation at beginning of year	$ 305,206	$ 241,645
Interest cost	11,746	12,214	11,135
Actuarial (gains) losses	(53,756)	56,749
Benefits paid	(6,416)	(5,402)
Benefit obligations at end of year	256,780	305,206	241,645
Change in Plan Assets:
Beginning balance	181,409	156,883
Actual return on plan assets	16,218	14,505
Employer contributions	16,909	15,423	34,100
Benefits paid	(6,416)	(5,402)
Ending balance	208,120	181,409	156,883
Amount Recognized in the Statement of Financial Position:
Current liabilities	(124)	(30)
Long-term liabilities	(48,536)	(123,767)
Net amount recognized	(48,660)	(123,797)
Amount Recognized in Accumulated Other Comprehensive Loss and not yet reflected in Net Periodic Benefit Cost:
Net actuarial loss	(83,601)	(154,678)
Accumulated other comprehensive loss	(83,601)	(154,678)
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	(6,879)	(14,721)
Amount recognized	$ (6,879)	$ (14,721)