Fair Value Measurements (Financial Assets Measured At Fair Value On A Recurring and Nonrecurring Basis) (Details) $ in Millions	9 Months Ended
	Oct. 29, 2016 USD ($)	Jul. 30, 2016 USD ($)	Oct. 31, 2015 USD ($)
Planned store closings	100
Carrying Value Of Long Lived Assets Held And Used		$ 326
Marketable equity and debt securities	$ 127		$ 98
Property, Plant, and Equipment, Fair Value Disclosure		$ 106
Impairment of Long-Lived Assets Held-for-use	220
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Marketable equity and debt securities	0		0
Significant Observable Inputs (Level 2) [Member]
Marketable equity and debt securities	127		98
Significant Unobservable Inputs (Level 3) [Member]
Marketable equity and debt securities	$ 0		$ 0