Fair Value Measurements (Details 2) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Mar. 03, 2012	Feb. 26, 2011
Student loan bonds [Member]
Fair Value, Assets Measured On Recurring Basis, Unobservable Input Reconciliation.
Balance at the beginning of the period	$ 108	$ 261
Changes in unrealized losses included in other comprehensive income	(1)	(1)
Sales	(27)	(152)
Balance at the end of the period	80	108
Municipal revenue bonds [Member]
Fair Value, Assets Measured On Recurring Basis, Unobservable Input Reconciliation.
Balance at the beginning of the period	2	19
Changes in unrealized losses included in other comprehensive income	0	1
Sales	0	(18)
Balance at the end of the period	2	2
Auction preferred securities
Fair Value, Assets Measured On Recurring Basis, Unobservable Input Reconciliation.
Balance at the beginning of the period	110	280
Changes in unrealized losses included in other comprehensive income	(1)	0
Sales	(27)	(170)
Balance at the end of the period	$ 82	$ 110