Earnings Per Share (Computation of Basic and Diluted Earnings Per Share) (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Oct. 29, 2016	Oct. 31, 2015	Oct. 29, 2016	Oct. 31, 2015
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Net Income	$ 157	$ 80	$ 475	$ 383
Weighted-average common shares outstanding	132.9	139.3	134.6	139.6
Dilutive effect of potential common shares	1.1	1.6	1.1	1.8
Weighted-average common shares outstanding assuming dilution	134.0	140.9	135.7	141.4
Basic earnings per share (in dollars per shares)	$ 1.18	$ 0.57	$ 3.53	$ 2.74
Diluted earnings per share (in dollars per share)	$ 1.17	$ 0.57	$ 3.50	$ 2.71
Stock Option Plans [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive share-based awards excluded from diluted calculation	0.5		0.4	0.6