Postretirement Health Care and Life Insurance Benefits (Reconciliation Of Benefit Obligations, Plan Assets, And Funded Status Of The Postretirement Obligations) (Details) - Other Postretirement Benefit Plan [Member] - USD ($) $ in Millions	12 Months Ended
	Jan. 30, 2016	Jan. 31, 2015	Feb. 01, 2014
Projected benefit obligation, beginning of year	$ 243	$ 223
Service cost	0	0	$ 0
Interest cost	8	10	10
Actuarial (gain) loss	(22)	30
Medicare Part D subsidy	1	1
Benefits paid	(18)	(21)
Projected benefit obligation, end of year	212	243	223
Fair value of plan assets, beginning of year	0	0
Company contributions	18	21
Fair value of plan assets, end of year	0	0	$ 0
Funded status at end of year	212	243
Accounts payable and accrued liabilities	(20)	(22)
Other liabilities	(192)	(221)
Defined Benefit Plan, Amounts Recognized in Balance Sheet	(212)	(243)
Net actuarial (gain) loss	(22)	$ 0
Defined Benefit Plan, Future Amortization of Gain (Loss)	$ 3