The Plans' Funded Status and Amounts Recognized in Company's Consolidated Balance Sheets (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Aug. 25, 2012	Aug. 27, 2011	Aug. 28, 2010
Change in Projected Benefit Obligation:
Projected benefit obligation at beginning of year	$ 241,645	$ 211,536
Interest cost	12,214	11,135	11,315
Actuarial losses	56,749	23,746
Benefits paid	(5,402)	(4,772)
Benefit obligations at end of year	305,206	241,645	211,536
Change in Plan Assets:
Beginning balance	156,883	117,243
Actual return on plan assets	14,505	10,336
Employer contributions	15,423	34,076	12
Benefits paid	(5,402)	(4,772)
Ending balance	181,409	156,883	117,243
Amount Recognized in the Statement of Financial Position:
Current liabilities	(30)	(27)
Long-term liabilities	(123,767)	(84,736)
Net amount recognized	(123,797)	(84,763)
Amount Recognized in Accumulated Other Comprehensive Loss and not yet reflected in Net Periodic Benefit Cost:
Net actuarial loss	(154,678)	(106,972)
Accumulated other comprehensive loss	(154,678)	(106,972)
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	(14,721)	(9,795)
Amount recognized	$ (14,721)	$ (9,795)