Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jul. 30, 2017	Jul. 31, 2016	Jul. 30, 2017	Jul. 31, 2016
Income Taxes
Income tax expense	$ 101	$ 56	$ 130	$ 89
Effective Income Tax Rate, Continuing Operations	14.80%	17.60%	10.70%	15.90%
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate	35.00%