Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended		12 Months Ended
	Oct. 28, 2018	Oct. 29, 2017	Oct. 28, 2018	Oct. 29, 2017	Jan. 28, 2018
Income Tax Disclosure [Abstract]
Income tax expense (benefit)	$ (149)	$ 58	$ (3)	$ 189
Tax expense (benefit) as percentage of income before income tax (as percent)	13.80%	6.50%		8.90%
Reduction in provisional U.S. tax reform tax amount	$ 138
U.S. federal statutory tax rate (as percent)			21.00%		33.90%