Fair Value Measurements (Detail) (USD $) In Thousands, unless otherwise specified	Aug. 24, 2012		Feb. 29, 2012		Aug. 26, 2011
Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total					$ 11,547
Recurring [Member] | Deferred Compensation Plan Assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets measured on a recurring basis	10,016	[1]	9,198	[1]	8,251	[1]
Recurring [Member] | Active Employees' Medical Plan Trust Assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets measured on a recurring basis					3,296
Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets held for sale					5,282
Total					5,282
Fair Value, Inputs, Level 1 [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total					11,547
Fair Value, Inputs, Level 1 [Member] | Recurring [Member] | Deferred Compensation Plan Assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets measured on a recurring basis	10,016	[1]	9,198	[1]	8,251	[1]
Fair Value, Inputs, Level 1 [Member] | Recurring [Member] | Active Employees' Medical Plan Trust Assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets measured on a recurring basis					3,296
Fair Value, Inputs, Level 2 [Member] | Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets held for sale					5,282
Total					$ 5,282

[1] There is an offsetting liability for the obligation to its employees on the Corporation's books.