Stock-Based Compensation (Summary Of Stock-Based Compensation Expense) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Oct. 29, 2016	Oct. 31, 2015	Oct. 29, 2016	Oct. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense, before income tax benefit	$ 21	$ 16	$ 68	$ 57
Income tax benefit	(7)	(5)	(22)	(18)
Total stock-based compensation expense, net of income tax benefit	14	11	46	39
Acquisition-related stock compensation [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense, before income tax benefit	2	5	10	14
Stock options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense, before income tax benefit	9	7	28	26
Restricted stock units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense, before income tax benefit	10	4	25	14
Performance share units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense, before income tax benefit	0	(1)	1	(1)
Other [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense, before income tax benefit	$ 0	$ 1	$ 4	$ 4