Retirement Plans (Summary Of Changes In Fair Value Of Pension Plan Level 3 Assets) (Details) (Pension Plan [Member], Significant Unobservable Inputs (Level 3) [Member], USD $) In Millions, unless otherwise specified	12 Months Ended
	Jan. 28, 2012	Jan. 29, 2011
Pension Plan [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair value of plan assets, beginning of year	$ 488	$ 413
Actual gain (loss) on plan assets:
Relating to assets still held at the reporting date	9	28
Relating to assets sold during the period	22	18
Purchases	48	69
Sales	(34)	(40)
Fair value of plan assets, end of year	$ 533	$ 488