Annual report pursuant to Section 13 and 15(d)

Fair Value Measurements and Concentrations of Credit Risk (Financial Assets Measured At Fair Value On A Recurring Basis) (Details)

v2.4.0.6
Fair Value Measurements and Concentrations of Credit Risk (Financial Assets Measured At Fair Value On A Recurring Basis) (Details) (USD $)
In Millions, unless otherwise specified
Jan. 28, 2012
Jan. 29, 2011
Marketable equity and debt securities $ 81 $ 95
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
   
Marketable equity and debt securities 0 41
Significant Observable Inputs (Level 2) [Member]
   
Marketable equity and debt securities 81 54
Significant Unobservable Inputs (Level 3) [Member]
   
Marketable equity and debt securities $ 0 $ 0