Income Taxes (Narrative) (Details) (USD $)
0 Months Ended 3 Months Ended 12 Months Ended
Jan. 27, 2014
Feb. 01, 2014
Jan. 31, 2015
Feb. 01, 2014
Feb. 02, 2013
Operating Loss Carryforwards [Line Items]          
Valuation allowance   $ 304,000,000 $ 784,000,000 $ 304,000,000  
Net tax expense (benefit)   270,000,000 23,000,000 (498,000,000) (551,000,000)
Operating loss carryforwards and tax credits, potential offset to future ordinary taxable income     1,100,000,000    
Amended rights agreement, stockholder ownership percentage, maximum 4.90%        
Amended rights agreement, Minimum stock ownership percentage by which stockholders are prevented from acquiring additional shares 4.90%        
Amount of unrecognized tax benefits that would impact effective tax rate if recognized   49,000,000 36,000,000 49,000,000 54,000,000
Benefit of federal tax deduction of state taxes     13,000,000 17,000,000 19,000,000
Accrued interest and penalties for unrecognized tax benefits   6,000,000 3,000,000 6,000,000 4,000,000
Actuarial Gains in Other Comprehensive Income [Member]          
Operating Loss Carryforwards [Line Items]          
Net tax expense (benefit)     (303,000,000)    
Federal [Member]          
Operating Loss Carryforwards [Line Items]          
Net operating loss carryforward     2,600,000,000    
Tax credit carryforwards     $ 53,000,000