Stockholders' Equity (Accumulated Other Comprehensive (Loss)/Income) (Details) (USD $)
In Millions, unless otherwise specified
 12 Months Ended
Jan. 28, 2012
Jan. 29, 2011
Jan. 30, 2010
Jan. 31, 2009
Net unrealized gains on real esate investments, Pre-Tax Amount $ 256 $ 174    
Net unrealized gains on real estate investments, Deferred Tax Liability (91)      
Net unrealized gains on real estate invstments, Net of Tax Amount 165 112    
Net actuarial (loss)/gain - pension and postretirement plans, Pre-Tax Amount (2,285) (1,568)    
Net actuarial (loss)/gain - pension and postretirement plans, Deferred Tax Asset 888 611    
Net actuarial (loss)/gain - pension and postretirement plans, Net of Tax Amount (1,397) (957)    
Prior service credit/(cost) - pension and postretirement plans, Pre-Tax Amount 38 66    
Prior service credit/(cost) - pension and postretirement plans - Deferred Tax Liability (15) (26)    
Prior service credit/(cost) - pension and postretirement plans - Net of Tax Amount 23 40    
Accumulated Other Comprehensive Income/(Loss), Pre-Tax (1,991) (1,328)    
Accumulated other comprehensive (loss), Deferred Tax Asset 782 523    
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest 4,010 5,460 4,778 4,155
Common Stock [Member]
        
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest 108 118 118 111
Additional Paid-in Capital [Member]
        
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest 3,699 3,925 3,867 3,499
Reinvested Earnings [Member]
        
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest 1,412 2,222 2,023 1,959
Accumulated Other Comprehensive (Loss)/Income [Member]
        
Net unrealized gains on real estate investments, Deferred Tax Liability   (62)    
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest $ (1,209) $ (805) $ (1,230) $ (1,414)