Stock Based Compensation Equity Incentive Plans (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
	Jan. 28, 2018		Jan. 29, 2017	Jan. 31, 2016
Amended and Restated 2007 Equity Incentive Plan
Number of shares may be issued under the Restated 2007 Plan	207.0
Number of Shares Available for Grant	16.0		22.0
Vesting percentage on the anniversary	25.00%
Quarterly vesting schedule - options	6.25%
Semi-annual vesting schedule - RSUs and PSUs for grants made prior to 5/18/16	12.50%
Quarterly vesting schedule - RSUs and PSUs for grants made on or after 5/18/16	6.25%
Maximum issuable shares of Market-based PSUs, percentage	100.00%
Amended and Restated 2012 Employee Stock Purchase Plan
Maximum Aggregated Number of Shares under 2012 ESPP	75.0
Total shares issued under ESPP	28.0
Shares reserved for future issuance under 2012 Plan	47.0
Maximum employee subscription rate	10.00%
Potential maximum employee subscription rate by BOD approval	15.00%
Purchase price of ESPP, percent	85.00%
RSUs, PSUs, and Market-Based PSUs
RSUs, PSUs and Market-based PSUs, outstanding, Number	22.0		27.0
RSUs, PSUs and Market-based PSUs, granted (in shares)	6.0	[1],[2]	12.0	13.0
RSUs, PSUs and Market-based PSUs, Vested in Period	(11.0)
RSUs, PSUs and Market-based PSUs, Forfeited in Period	0.0
Weighted average grant date fair value, RSUs, PSUs and Market-based PSUs, Outstanding	$ 66.72		$ 32.84
Weighted average grant date fair value, RSUs, PSUs, and Market-based PSUs, granted	145.91		$ 50.57	$ 22.01
RSUs, PSUs and Market-based PSUs, Vested in Period, Weighted Average Grant Date Fair Value	28.80
RSUs, PSUs and Market-based PSUs, Forfeited in Period, Weighted Average Grant Date Fair Value	$ 0.00
Vested and expected to vest, RSUs, PSUs and Market-based PSUs	18.0
Weighted Average Grant Date Fair Value, RSUs, PSUs and Market-based PSUs, Vested and expected to vest	$ 66.43
Maximum number of market-based PSUs issuable	0.1
Number of Shares Available for Grant	16.0		22.0
Options, Exercises in Period, Total Intrinsic Value	$ 318		$ 246	$ 75
Total fair value of Options, Vested in Period	$ 1		$ 8	$ 17

[1] Includes PSUs that will be issued and eligible to vest based on the corporate financial performance maximum target level achieved for fiscal year 2018.

[2] Includes market-based PSUs that will be issued and eligible to vest if the maximum target for total shareholder return, or TSR, over the 3-year measurement period is achieved.