Stockholders' Equity (Accumulated Other Comprehensive (Loss)/Income) (Details) (Accumulated Other Comprehensive (Loss)/Income [Member], USD $)
In Millions
Apr. 30, 2011
Jan. 29, 2011
Accumulated Other Comprehensive (Loss)/Income [Member]
   
Net unrealized gains on REITs, Net of Tax $ 135 $ 112
Net unrealized gains on REITs, Deferred Tax 75 62
Net actuarial (loss)/gain and prior service (cost)/credit - pension and postretirement plans, Net of Tax (898) (917)
Net actuarial (loss)/gain and prior service (cost)/credit - pension and postretirement plans, Deferred Tax Asset $ 573 $ 585