Retirement Plans (Fair Value Of Pension Plan Assets) (Details) - USD ($) $ in Millions	Jan. 30, 2016	Jan. 31, 2015
Fair value of pension investments	$ 132	$ 97
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Fair value of pension investments	0	0
Significant Observable Inputs (Level 2) [Member]
Fair value of pension investments	132	97
Significant Unobservable Inputs (Level 3) [Member]
Fair value of pension investments	0	0
Pension Plan [Member]
Fair value of pension investments	3,246	3,685
Pension Plan [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Fair value of pension investments	295	344
Pension Plan [Member] | Significant Observable Inputs (Level 2) [Member]
Fair value of pension investments	907	1,007
Pension Plan [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair value of pension investments	0	0
Pension Plan [Member] | Cash and Cash Equivalents [Member]
Fair value of pension investments	15
Pension Plan [Member] | Cash and Cash Equivalents [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Fair value of pension investments	15
Pension Plan [Member] | Cash and Cash Equivalents [Member] | Significant Observable Inputs (Level 2) [Member]
Fair value of pension investments	0
Pension Plan [Member] | Cash and Cash Equivalents [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair value of pension investments	0
Pension Plan [Member] | Money market securities [Member]
Fair value of pension investments	36	108
Pension Plan [Member] | Money market securities [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Fair value of pension investments	0	0
Pension Plan [Member] | Money market securities [Member] | Significant Observable Inputs (Level 2) [Member]
Fair value of pension investments	36	108
Pension Plan [Member] | Money market securities [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair value of pension investments	0	0
Pension Plan [Member] | Money market pooled funds [Member]
Fair value of pension investments	46	140
Pension Plan [Member] | Money market pooled funds [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Fair value of pension investments	0	0
Pension Plan [Member] | Money market pooled funds [Member] | Significant Observable Inputs (Level 2) [Member]
Fair value of pension investments	0	0
Pension Plan [Member] | Money market pooled funds [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair value of pension investments	0	0
Pension Plan [Member] | Equity securities [Member] | UNITED STATES
Fair value of pension investments	280	344
Pension Plan [Member] | Equity securities [Member] | United States pooled funds [Member]
Fair value of pension investments	391	477
Pension Plan [Member] | Equity securities [Member] | International [Member]
Fair value of pension investments	575	659
Pension Plan [Member] | Equity securities [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | UNITED STATES
Fair value of pension investments	280	344
Pension Plan [Member] | Equity securities [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | United States pooled funds [Member]
Fair value of pension investments	0	0
Pension Plan [Member] | Equity securities [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | International [Member]
Fair value of pension investments	0	0
Pension Plan [Member] | Equity securities [Member] | Significant Observable Inputs (Level 2) [Member] | UNITED STATES
Fair value of pension investments	0	0
Pension Plan [Member] | Equity securities [Member] | Significant Observable Inputs (Level 2) [Member] | United States pooled funds [Member]
Fair value of pension investments	0	0
Pension Plan [Member] | Equity securities [Member] | Significant Observable Inputs (Level 2) [Member] | International [Member]
Fair value of pension investments	0	0
Pension Plan [Member] | Equity securities [Member] | Significant Unobservable Inputs (Level 3) [Member] | UNITED STATES
Fair value of pension investments	0	0
Pension Plan [Member] | Equity securities [Member] | Significant Unobservable Inputs (Level 3) [Member] | United States pooled funds [Member]
Fair value of pension investments	0	0
Pension Plan [Member] | Equity securities [Member] | Significant Unobservable Inputs (Level 3) [Member] | International [Member]
Fair value of pension investments	0	0
Pension Plan [Member] | U.S. Treasury bonds [Member]
Fair value of pension investments	233	272
Pension Plan [Member] | U.S. Treasury bonds [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Fair value of pension investments	0	0
Pension Plan [Member] | U.S. Treasury bonds [Member] | Significant Observable Inputs (Level 2) [Member]
Fair value of pension investments	233	272
Pension Plan [Member] | U.S. Treasury bonds [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair value of pension investments	0	0
Pension Plan [Member] | Other Government bonds [Member]
Fair value of pension investments	41	55
Pension Plan [Member] | Other Government bonds [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Fair value of pension investments	0	0
Pension Plan [Member] | Other Government bonds [Member] | Significant Observable Inputs (Level 2) [Member]
Fair value of pension investments	41	55
Pension Plan [Member] | Other Government bonds [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair value of pension investments	0	0
Pension Plan [Member] | Agency backed bonds [Member]
Fair value of pension investments	31	28
Pension Plan [Member] | Agency backed bonds [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Fair value of pension investments	0	0
Pension Plan [Member] | Agency backed bonds [Member] | Significant Observable Inputs (Level 2) [Member]
Fair value of pension investments	31	28
Pension Plan [Member] | Agency backed bonds [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair value of pension investments	0	0
Pension Plan [Member] | Corporate bonds [Member]
Fair value of pension investments	433	434
Pension Plan [Member] | Corporate bonds [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Fair value of pension investments	0	0
Pension Plan [Member] | Corporate bonds [Member] | Significant Observable Inputs (Level 2) [Member]
Fair value of pension investments	433	434
Pension Plan [Member] | Corporate bonds [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair value of pension investments	0	0
Pension Plan [Member] | Mortgage-backed securities and forwards [Member]
Fair value of pension investments	112	102
Pension Plan [Member] | Mortgage-backed securities and forwards [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Fair value of pension investments	0	0
Pension Plan [Member] | Mortgage-backed securities and forwards [Member] | Significant Observable Inputs (Level 2) [Member]
Fair value of pension investments	112	102
Pension Plan [Member] | Mortgage-backed securities and forwards [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair value of pension investments	0	0
Pension Plan [Member] | Asset-backed securities [Member]
Fair value of pension investments	28	19
Pension Plan [Member] | Asset-backed securities [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Fair value of pension investments	0	0
Pension Plan [Member] | Asset-backed securities [Member] | Significant Observable Inputs (Level 2) [Member]
Fair value of pension investments	28	19
Pension Plan [Member] | Asset-backed securities [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair value of pension investments	0	0
Pension Plan [Member] | Pooled funds [Member]
Fair value of pension investments	427	458
Pension Plan [Member] | Pooled funds [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Fair value of pension investments	0	0
Pension Plan [Member] | Pooled funds [Member] | Significant Observable Inputs (Level 2) [Member]
Fair value of pension investments	0	0
Pension Plan [Member] | Pooled funds [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair value of pension investments	0	0
Pension Plan [Member] | Real Estate [Member]
Fair value of pension investments	238	244
Pension Plan [Member] | Real Estate [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Fair value of pension investments	0	0
Pension Plan [Member] | Real Estate [Member] | Significant Observable Inputs (Level 2) [Member]
Fair value of pension investments	0	0
Pension Plan [Member] | Real Estate [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair value of pension investments	0	0
Pension Plan [Member] | Hedge Funds [Member]
Fair value of pension investments	179	175
Pension Plan [Member] | Hedge Funds [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Fair value of pension investments	0	0
Pension Plan [Member] | Hedge Funds [Member] | Significant Observable Inputs (Level 2) [Member]
Fair value of pension investments	0	0
Pension Plan [Member] | Hedge Funds [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair value of pension investments	0	0
Pension Plan [Member] | Private equity [Member]
Fair value of pension investments	188	181
Pension Plan [Member] | Private equity [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Fair value of pension investments	0	0
Pension Plan [Member] | Private equity [Member] | Significant Observable Inputs (Level 2) [Member]
Fair value of pension investments	0	0
Pension Plan [Member] | Private equity [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair value of pension investments	0	0
Pension Plan [Member] | Derivatives in a positive position [Member]
Fair value of pension investments	15	27
Pension Plan [Member] | Derivatives in a positive position [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Fair value of pension investments	0	0
Pension Plan [Member] | Derivatives in a positive position [Member] | Significant Observable Inputs (Level 2) [Member]
Fair value of pension investments	15	27
Pension Plan [Member] | Derivatives in a positive position [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair value of pension investments	0	0
Pension Plan [Member] | Derivatives in a negative position [Member]
Fair value of pension investments	(22)	(38)
Pension Plan [Member] | Derivatives in a negative position [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Fair value of pension investments	0	0
Pension Plan [Member] | Derivatives in a negative position [Member] | Significant Observable Inputs (Level 2) [Member]
Fair value of pension investments	(22)	(38)
Pension Plan [Member] | Derivatives in a negative position [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair value of pension investments	$ 0	$ 0