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)

v2.4.1.9
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. 31, 2015
Feb. 01, 2014
Marketable equity and debt securities $ 97us-gaap_InvestmentsFairValueDisclosure $ 75us-gaap_InvestmentsFairValueDisclosure
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]    
Marketable equity and debt securities 0us-gaap_InvestmentsFairValueDisclosure
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
0us-gaap_InvestmentsFairValueDisclosure
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
Significant Observable Inputs (Level 2) [Member]    
Marketable equity and debt securities 97us-gaap_InvestmentsFairValueDisclosure
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
75us-gaap_InvestmentsFairValueDisclosure
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
Significant Unobservable Inputs (Level 3) [Member]    
Marketable equity and debt securities $ 0us-gaap_InvestmentsFairValueDisclosure
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
$ 0us-gaap_InvestmentsFairValueDisclosure
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member