Postretirement Health Care and Life Insurance Benefits (Net Periodic Benefit Cost) (Details) (Other Postretirement Benefit Plan [Member], USD $) In Millions, unless otherwise specified	12 Months Ended
	Jan. 31, 2015	Feb. 01, 2014	Feb. 02, 2013
Other Postretirement Benefit Plan [Member]
Service cost	$ 0	$ 0	$ 0
Interest cost	10	10	12
Amortization of net actuarial (gain) loss	(5)	(3)	(4)
Amortization of prior service credit	0	0	0
Total net periodic benefit cost	5	7	8
Net actuarial (gain) loss recognized in OCI before tax	30	(15)	(4)
Amortization of net actuarial loss	5	3	4
Amortization of prior service credit	0	0	0
Total recognized in other comprehensive income	35	(12)	0
Total recognized in net periodic benefit cost and other comprehensive income	$ 40	$ (5)	$ 8