New Lease Accounting Standard - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jul. 28, 2019	Jul. 29, 2018	Jul. 28, 2019	Jul. 29, 2018	Jan. 28, 2019	Jan. 27, 2019
Leases [Abstract]
Operating lease assets	$ 535		$ 535		$ 470	$ 0
Operating lease liabilities	567		567		$ 500
Deferred rent credit						$ 30
Operating lease expense	$ 28	$ 20	$ 55	$ 36
Weighted average remaining lease term - operating leases	8 years 8 months 12 days		8 years 8 months 12 days
Weighted average discount rate - operating leases	3.70%		3.70%