Retirement Benefit Plans (Defined Benefit Plans) (Details) (USD $)
In Millions, unless otherwise specified
0 Months Ended 12 Months Ended 0 Months Ended 12 Months Ended 0 Months Ended 12 Months Ended 0 Months Ended 9 Months Ended 0 Months Ended 9 Months Ended
Oct. 15, 2011
May 24, 2010
Feb. 02, 2013
Jan. 29, 2011
Sep. 30, 2012
Jan. 28, 2012
Oct. 01, 2011
Sep. 30, 2012
Primary Plan Benefits [Member]
Oct. 15, 2011
Primary Plan Benefits [Member]
Feb. 02, 2013
Primary Plan Benefits [Member]
Jan. 28, 2012
Primary Plan Benefits [Member]
Sep. 30, 2012
Supplemental Plan Benefits [Member]
Feb. 02, 2013
Supplemental Plan Benefits [Member]
Jan. 28, 2012
Supplemental Plan Benefits [Member]
Oct. 15, 2011
Supplemental Retirement Program [Member]
Oct. 15, 2011
Supplemental Retirement Program [Member]
Oct. 15, 2011
Benefit Restoration Plan [Member]
Oct. 15, 2011
Benefit Restoration Plan [Member]
Enhanced Retirement Beneifts, Number of Employees Eligible             8,000                      
Enhanced Reitirement Benefits, Number of Employees Accepted 4,000                                  
Special termination benefits $ 176               $ 133   $ 133     $ 43 $ 36   $ 7  
Curtailments                   (80)     (13)          
Discount rate 5.06%   4.19% 5.65% 4.25% 4.82%                        
Projected benefit obligation, period increase/(decrease)               166       55       71   24
Defined Benefit Plan Funded Status Of Plan Percentage     As of the end of 2012, the funded status of the Primary Pension Plan was just under 100%. The PBO is the present value of benefits earned to date by plan participants, including the effect of assumed future salary increases. Under the Employee Retirement Income Security Act of 1974 (ERISA), the funded status of the plan exceeded 100% as of December 31, 2012 and 2011, the qualified pension plan's year end.                              
Defined Benefit Plan, Actual Return on Plan Assets, Percent     13.00%                              
Defined Benefit Plan, Cumulative Return on Plan Assets Since Inception, Percent     9.00%                              
Defined Benefit Plan, Accumulated Benefit Obligation                   4,700 4,900   268 272        
Pension contribution from issuance of $400 million of 5.65% Senior Notes due 2020   392   392                            
Defined Benefit Plan, Expected Future Benefit Payments in Year One                   $ 358     $ 53