Comprehensive Income (Components Of Accumulated Other Comprehensive Income (Loss)) (Details) - USD ($)
$ in Millions
 3 Months Ended 9 Months Ended
Oct. 29, 2016
Apr. 30, 2016
Oct. 31, 2015
Oct. 29, 2016
Oct. 31, 2015
Accumulated Other Comprehensive Income (Loss), Beginning Balance   $ 40   $ 40 $ 35
Other Comprehensive Income (Loss), before Reclassifications, before Tax       (32) 14
Amounts Reclassified from Accumulated Other Comprehensive Income (Loss)       1 (7)
Other Comprehensive Income (Loss), Tax       3 (1)
Current-period Other Comprehensive Income (Loss) $ (10)   $ 0 (28) 6
Accumulated Other Comprehensive Income (Loss), Ending Balance 12   41 12 41
Other Income 3   0 83 75
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, Net of Tax 0 (3) 0 (3) 0
Available-for-sale Securities, Gross Realized Gains       (4) 0
Provision for Income Taxes 68   96 277 335
Net Income 122   164 526 617
Accumulated Translation Adjustment [Member]          
Accumulated Other Comprehensive Income (Loss), Beginning Balance   28   28 51
Other Comprehensive Income (Loss), before Reclassifications, before Tax       (25) 5
Amounts Reclassified from Accumulated Other Comprehensive Income (Loss)       0 0
Other Comprehensive Income (Loss), Tax       0 0
Current-period Other Comprehensive Income (Loss)       (25) 5
Accumulated Other Comprehensive Income (Loss), Ending Balance 3   56 3 56
Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member]          
Accumulated Other Comprehensive Income (Loss), Beginning Balance   4   4 (16)
Other Comprehensive Income (Loss), before Reclassifications, before Tax       (1) 6
Amounts Reclassified from Accumulated Other Comprehensive Income (Loss)       5 (7)
Other Comprehensive Income (Loss), Tax       (1) 0
Current-period Other Comprehensive Income (Loss)       3 (1)
Accumulated Other Comprehensive Income (Loss), Ending Balance 7   (17) 7 (17)
Accumulated Net Investment Gain (Loss) Attributable to Parent [Member]          
Accumulated Other Comprehensive Income (Loss), Beginning Balance   8   8 0
Other Comprehensive Income (Loss), before Reclassifications, before Tax       (6) 3
Amounts Reclassified from Accumulated Other Comprehensive Income (Loss)       (4) 0
Other Comprehensive Income (Loss), Tax       4 (1)
Current-period Other Comprehensive Income (Loss)       (6) 2
Accumulated Other Comprehensive Income (Loss), Ending Balance 2   2 2 2
Reclassification out of Accumulated Other Comprehensive Income [Member] | Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member]          
Other Income (4)   3 5 (7)
Provision for Income Taxes 0   0 0 0
Net Income (4)   3 5 (7)
Reclassification out of Accumulated Other Comprehensive Income [Member] | Accumulated Net Investment Gain (Loss) Attributable to Parent [Member]          
Other Income     $ 0   $ 0
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, Tax 0     1  
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, Net of Tax 0     (3)  
Available-for-sale Securities, Gross Realized Gains $ 0 $ (4)   $ (4)