Pension and Postretirement Health Care Plans - Schedule of Change in Accumulated Other Comprehensive Income (Details) - Pension Plan - USD ($) $ in Millions	12 Months Ended
	Jan. 30, 2016	Jan. 31, 2015
Pretax
Beginning balance	$ 949	$ 712
Net actuarial loss	87	291
Amortization of net actuarial losses	(82)	(65)
Amortization of prior service costs and transition	11	11
Ending balance	965	949
Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, before Reclassification Adjustments, Net of Tax [Abstract]
Beginning balance	573	430
Net actuarial loss	53	176
Amortization of net actuarial losses	(50)	(40)
Amortization of prior service costs and transition	7	7
Ending balance	$ 583	$ 573