Notes Payable and Long-Term Debt (Details) (USD $)	6 Months Ended	0 Months Ended	6 Months Ended	3 Months Ended	6 Months Ended	3 Months Ended		6 Months Ended
	Aug. 03, 2013	Mar. 13, 2013 Secured	Aug. 03, 2013 Secured	May 04, 2013 Unsecured	Aug. 03, 2013 Unsecured	Aug. 03, 2013 Commercial paper	Jul. 28, 2012 Commercial paper	Aug. 03, 2013 Commercial paper	Jul. 28, 2012 Commercial paper
Debt Instrument Line Items
Maximum daily amount outstanding during the period						$ 920,000,000	$ 620,000,000	$ 1,465,000,000	$ 620,000,000
Average daily amount outstanding during the period						301,000,000	240,000,000	394,000,000	201,000,000
Amount outstanding at period-end						807,000,000		807,000,000
Weighted average interest rate (as a percent)						0.19%	0.21%	0.14%	0.16%
Debt amount repaid		1,500,000,000	1,500,000,000
Cash proceeds from the sale to repurchase additional debt				1,400,000,000
Repurchase of additional debt				970,000,000
Loss on early retirement	$ 445,000,000				$ 445,000,000