Retirement Plans (Net Periodic Benefit Cost) (Details) - USD ($) $ in Millions	3 Months Ended				12 Months Ended
	Jan. 28, 2017	Oct. 29, 2016	Jul. 30, 2016	Apr. 30, 2016	Jan. 28, 2017	Jan. 30, 2016	Jan. 31, 2015
Settlement charges	$ (17)	$ (62)	$ (6)	$ (13)	$ (98)	$ 0	$ 0
Settlement charges	$ 17	$ 62	$ 6	$ 13	98	0	0
Supplemental Employee Retirement Plan
Service cost					0	0	0
Interest cost					22	31	33
Amortization of net actuarial (gain) loss					9	10	5
Amortization of prior service credit					0	0	0
Total net periodic benefit cost					31	41	38
Settlement charges					30	0	0
Net actuarial (gain) loss recognized in OCI before tax					26	(70)	170
Amortization of net actuarial loss					(9)	(10)	(5)
Amortization of prior service credit					0	0	0
Settlement charges					(30)	0	0
Total recognized in other comprehensive income					(13)	(80)	165
Total recognized in net periodic benefit cost and other comprehensive income					48	(39)	203
Pension Plan [Member]
Service cost					5	6	6
Interest cost					108	137	151
Expected return on assets					(227)	(235)	(246)
Amortization of net actuarial (gain) loss					31	38	25
Amortization of prior service credit					0	0	0
Total net periodic benefit cost					(83)	(54)	(64)
Settlement charges					68	0	0
Net actuarial (gain) loss recognized in OCI before tax					(120)	92	491
Amortization of net actuarial loss					(31)	(38)	(25)
Amortization of prior service credit					0	0	0
Settlement charges					(68)	0	0
Total recognized in other comprehensive income					(219)	54	466
Total recognized in net periodic benefit cost and other comprehensive income					$ (234)	$ 0	$ 402