Earnings per share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 28, 2016	Oct. 30, 2015	Oct. 28, 2016	Oct. 30, 2015
Net Income
Basic Earnings	$ 235,315	$ 253,321	$ 836,957	$ 788,905
Diluted Earnings	$ 235,315	$ 253,321	$ 836,957	$ 788,905
Shares
Shares outstanding, basic	280,441	292,037	283,152	296,307
Effect of dilutive share-based awards	842	867	974	867
Shares outstanding, diluted	281,283	292,904	284,126	297,174
Per Share Amount
Basic earnings per share (in dollars per share)	$ 0.84	$ 0.87	$ 2.96	$ 2.66
Diluted earnings per share (in dollars per share)	$ 0.84	$ 0.86	$ 2.95	$ 2.65
Share-based awards outstanding excluded from computation of diluted earnings per share	1,900	1,600	1,600	1,200