Shareholders' Equity (Summary Of Share Repurchase Activity) (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
	Jan. 28, 2017	Jan. 30, 2016	Jan. 31, 2015
Share Repurchase Program [Line Items]
Capacity beginning balance	$ 811	$ 1,075	$ 670
Shares repurchased (in shares)	5.9	19.1	8.9
Shares repurchased, average price per share (in dollars per share)	$ 48	$ 63	$ 66
Shares repurchased (amount)	$ (282)	$ (1,191)	$ (595)
Capacity ending balance	529	811	1,075
2013 Program [Member]
Share Repurchase Program [Line Items]
Expiration of unused capacity in March 2015		(73)
2014 Program [Member]
Share Repurchase Program [Line Items]
Share repurchase authorization			$ 1,000
2015 Program [Member]
Share Repurchase Program [Line Items]
Capacity beginning balance
Share repurchase authorization		$ 1,000
Capacity ending balance	$ 529