Deferred Costs (Details) (USD $)	Nov. 25, 2011	Feb. 28, 2011	Nov. 26, 2010
Deferred costs and future payment commitments for retail supply agreements
Prepaid expenses and other	$ 93,553,000	$ 88,352,000	$ 89,250,000
Other assets	307,611,000	327,311,000	284,908,000
Deferred cost assets	401,164,000	415,663,000	374,158,000
Other current liabilities	(58,950,000)	(64,116,000)	(54,048,000)
Other liabilities	(64,154,000)	(76,301,000)	(50,900,000)
Deferred cost liabilities	(123,104,000)	(140,417,000)	(104,948,000)
Net deferred costs	278,060,000	275,246,000	269,210,000
Deferred Costs (Textuals) [Abstract]
Allowance for deferred costs related to supply	$ 10,000,000	$ 10,700,000	$ 11,100,000