Capital Structure (Details) (USD $) Share data in Millions, except Per Share data, unless otherwise specified	12 Months Ended			1 Months Ended								12 Months Ended		12 Months Ended															12 Months Ended		12 Months Ended		12 Months Ended				12 Months Ended	0 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Feb. 29, 2012 6.125% Senior Notes, due 2012	Dec. 31, 2011 6.125% Senior Notes, due 2012	Dec. 31, 2012 7.50% Debentures, due 2013	Dec. 31, 2011 7.50% Debentures, due 2013	Dec. 31, 2012 5.00% Senior Notes, due 2014	Dec. 31, 2011 5.00% Senior Notes, due 2014	Dec. 31, 2012 6.20% Senior Notes, due 2014	Dec. 31, 2011 6.20% Senior Notes, due 2014	Dec. 31, 2012 6.75% Senior Debentures, due 2018	Dec. 31, 2011 6.75% Senior Debentures, due 2018	Dec. 31, 2012 6.75% Senior Debentures, due 2018 Maximum	Dec. 31, 2012 7.45% Senior Notes, due 2019	Dec. 31, 2011 7.45% Senior Notes, due 2019	Dec. 31, 2012 6.125% Senior Notes, due 2032	Dec. 31, 2011 6.125% Senior Notes, due 2032	Dec. 31, 2012 5.350% Senior Notes due 2033	Dec. 31, 2011 5.350% Senior Notes due 2033	Dec. 31, 2012 5.55% Senior Notes due 2035	Dec. 31, 2011 5.55% Senior Notes due 2035	Dec. 31, 2012 5.95% Senior Notes, due 2036	Dec. 31, 2011 5.95% Senior Notes, due 2036	Dec. 31, 2012 6.90% Senior Debentures, due 2038	Dec. 31, 2011 6.90% Senior Debentures, due 2038	Dec. 31, 2012 5.20% Senior Notes due 2042	Jan. 11, 2012 5.20% Senior Notes due 2042	Dec. 31, 2012 6.125% Junior Subordinated Debentures, due 2067	Dec. 31, 2011 6.125% Junior Subordinated Debentures, due 2067	Dec. 31, 2012 6.50% Junior Subordinated Debentures, due 2067	Dec. 31, 2011 6.50% Junior Subordinated Debentures, due 2067	Dec. 31, 2012 Synthetic lease VIE obligations, floating rates, due 2014 store	Dec. 31, 2011 Synthetic lease VIE obligations, floating rates, due 2014	Dec. 31, 2012 Federal Home Loan Bank ("FHLB") advances, due 2018	Dec. 31, 2011 Federal Home Loan Bank ("FHLB") advances, due 2018	Dec. 31, 2012 The Debentures	Jan. 10, 2013 5.10% Senior Notes due 2053 Subsequent event
Debt outstanding:
Total long-term debt	$ 6,057,000,000	$ 5,908,000,000			$ 350,000,000	$ 250,000,000	$ 250,000,000	$ 650,000,000	$ 650,000,000	$ 300,000,000	$ 300,000,000	$ 250,000,000	$ 250,000,000		$ 700,000,000	$ 700,000,000	$ 250,000,000	$ 250,000,000	$ 400,000,000	$ 400,000,000	$ 800,000,000	$ 800,000,000	$ 650,000,000	$ 650,000,000	$ 250,000,000	$ 250,000,000	$ 500,000,000		$ 500,000,000	$ 500,000,000	$ 500,000,000	$ 500,000,000	$ 44,000,000	$ 44,000,000	$ 13,000,000	$ 14,000,000		$ 500,000,000
Total debt	6,057,000,000	5,908,000,000
Note stated interest rate (as a percent)				6.125%	6.125%	7.50%	7.50%	5.00%	5.00%	6.20%	6.20%	6.75%	6.75%		7.45%	7.45%	6.125%	6.125%	5.35%	5.35%	5.55%	5.55%	5.95%	5.95%	6.90%	6.90%	5.20%	5.20%	6.125%	6.125%	6.50%	6.50%						5.10%
Minimum principal outstanding amount for redemption of debt in whole or in part																																						25,000,000
Period after occurrence of certain tax and rating agency events in which redemption of debt in whole permissible																																						90 days
Redemption price as percentage of principal amount plus accrued and unpaid interest	100.00%
Face amount of debt issued																												500,000,000
Repayment of the senior notes				350,000,000
Interest on debentures payment terms																													three-month LIBOR		three-month LIBOR							three-month LIBOR
Interest rate spread over LIBOR (as a percent)																													1.935%		2.12%							3.165%
Maximum period for deferment of interest payment																																					10 years	5 years
Reserved common stock authorized and unissued for debentures obligations (in shares)																																					75
Threshold percentage of repurchase or redemption of outstanding principal debentures for non applicability of promises and covenants contained in the new RCC												10.00%
Period within which threshold percentage of outstanding principal of debentures is to be purchased for non applicability of promises and covenants contained in the new RCC												1 year
Percentage of repurchase or redemption of outstanding principal debentures within specified period for non applicability of promises and covenants contained in the new RCC														25.00%
Specified period within which percentage of outstanding principal of debentures is to be purchased for non applicability of promises and covenants contained in the new RCC												10 years
Maximum number of stores acquired																																	19
Renewal term for synthetic lease																																		3 years
Property and equipment, net																																	30,000,000	32,000,000
Unsecured revolving credit facility	1,000,000,000
Commercial Paper maximum borrowing capacity	1,000,000,000
Credit facility initial term	5 years
Terms for extension of credit facility	The Company has the option to extend the expiration by one year at the first and second anniversary of the facility, upon approval of existing or replacement lenders.
Additional borrowing capacity under credit facility increase provision	500,000,000
Maximum debt to capital ratio allowed under credit facility covenant (as a percent)	37.50%
Interest paid on debt	$ 366,000,000	$ 363,000,000	$ 363,000,000
Capital stock
Common stock, shares issued	900	900
Common stock, shares outstanding	479	501
Treasury stock, shares	421	399
Reacquired shares	27
Average cost of reacquired shares (in dollars per share)	$ 34.11
Reissued shares under equity incentive plans	5