Fair Value Measurements (Assets And Liabilities Measured At Fair Value On A Nonrecurring Basis) (Details) (USD $) In Millions, unless otherwise specified	6 Months Ended
	Jul. 29, 2012	Jul. 31, 2011
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Gain (Losses)	$ 1	$ 7
Business Restructuring Reserves [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Gain (Losses)	1	7
Business Restructuring Reserves [Member] | Fair Value, Measurements, Nonrecurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Lease obligation costs, net	$ (132)	$ (139)