Financing (Schedule of Company Debt) (Details) - USD ($) $ in Millions	Jan. 28, 2017	Jan. 30, 2016	Dec. 07, 2015	Nov. 18, 2014	May 23, 2014
Unamortized debt issue costs	$ (29)	$ (32)
Unamortized debt discount	(16)	(16)
2.875% Senior notes due 2023 [Member]
Debt instrument, principal outstanding	$ 750	750
Debt instrument interest rate, stated percentage	2.875%
3.875% Senior notes due 2022 [Member]
Debt instrument, principal outstanding	$ 550	550
Debt instrument interest rate, stated percentage	3.875%
4.5% senior notes due 2034[Member]
Debt instrument, principal outstanding	$ 550	550
Debt instrument interest rate, stated percentage	4.50%			4.50%
3.45% senior notes due 2021 [Member]
Debt instrument, principal outstanding	$ 500	500
Debt instrument interest rate, stated percentage	3.45%		3.45%
3.625% senior notes due 2024 [Member]
Debt instrument, principal outstanding	$ 500	500
Debt instrument interest rate, stated percentage	3.625%				3.625%
6.375% Senior Notes Due 2037 [Member]
Debt instrument, principal outstanding	$ 500	500
Debt instrument interest rate, stated percentage	6.375%
4.375% Senior notes due 2023 [Member]
Debt instrument, principal outstanding	$ 400	400
Debt instrument interest rate, stated percentage	4.375%
6.9% Senior Debentures Due 2029 [Member]
Debt instrument, principal outstanding	$ 400	400
Debt instrument interest rate, stated percentage	6.90%
6.7% Senior Debentures Due 2034 [Member]
Debt instrument, principal outstanding	$ 400	400
Debt instrument interest rate, stated percentage	6.70%
7.45% Senior Debentures Due 2017 [Member]
Debt instrument, principal outstanding	$ 0	300
Debt instrument interest rate, stated percentage	7.45%
6.65% Senior Debentures Due 2024 [Member]
Debt instrument, principal outstanding	$ 300	300
Debt instrument interest rate, stated percentage	6.65%
7.0% Senior Debentures Due 2028 [Member]
Debt instrument, principal outstanding	$ 300	300
Debt instrument interest rate, stated percentage	7.00%
6.9% Senior Debentures Due 2032 [Member]
Debt instrument, principal outstanding	$ 250	250
Debt instrument interest rate, stated percentage	6.90%
5.125% Senior debentures due 2042 [Member]
Debt instrument, principal outstanding	$ 250	250
Debt instrument interest rate, stated percentage	5.125%
4.3% Senior notes due 2043 [Member]
Debt instrument, principal outstanding	$ 250	250
Debt instrument interest rate, stated percentage	4.30%
6.7% Senior Debentures Due 2028 [Member]
Debt instrument, principal outstanding	$ 200	200
Debt instrument interest rate, stated percentage	6.70%
6.79% Senior Debentures Due 2027 [Member]
Debt instrument, principal outstanding	$ 165	165
Debt instrument interest rate, stated percentage	6.79%
7.875% Senior Debentures Due 2036 [Member]
Debt instrument, principal outstanding	$ 0	108
Debt instrument interest rate, stated percentage	7.875%
8.75% Senior Debentures Due 2029 [Member]
Debt instrument, principal outstanding	$ 61	61
Debt instrument interest rate, stated percentage	8.75%
8.5% Senior Debentures Due 2019 [Member]
Debt instrument, principal outstanding	$ 36	36
Debt instrument interest rate, stated percentage	8.50%
10.25% Senior Debentures Due 2021 [Member]
Debt instrument, principal outstanding	$ 33	33
Debt instrument interest rate, stated percentage	10.25%
9.5% Amortizing Debentures Due 2021 [Member]
Debt instrument, principal outstanding	$ 14	17
Debt instrument interest rate, stated percentage	9.50%
7.6% Senior Debentures Due 2025 [Member]
Debt instrument, principal outstanding	$ 24	24
Debt instrument interest rate, stated percentage	7.60%
9.75% Amortizing Debentures Due 2021 [Member]
Debt instrument, principal outstanding	$ 8	9
Debt instrument interest rate, stated percentage	9.75%
7.875% Senior Debentures Due 2030 [Member]
Debt instrument, principal outstanding	$ 18	18
Debt instrument interest rate, stated percentage	7.875%
Premium on acquired debt
Debt instrument, principal outstanding	$ 121	143
Premium on acquired debt | Minimum [Member]
Debt instrument interest rate, effective percentage	5.542%
Premium on acquired debt | Maximum [Member]
Debt instrument interest rate, effective percentage	6.021%
Capital Lease and Other Long-Term Obligations [Member]
Debt instrument, principal outstanding	$ 27	29
Total Of Long Term Debt [Member]
Debt instrument, principal outstanding	6,562	6,995
7.45% Senior debentures due 2017 [Member]
Debt instrument, principal outstanding	$ 300	0
Debt instrument interest rate, stated percentage	7.45%
5.90% Senior Notes Due 2016 [Member]
Debt instrument, principal outstanding	$ 0	577
Debt instrument interest rate, stated percentage	5.90%
7.45% Senior Debentures Due 2016 [Member]
Debt instrument, principal outstanding	$ 0	59
Debt instrument interest rate, stated percentage	7.45%
Capital Lease and Current Portion of Other Long-Term Obligations
Debt instrument, principal outstanding	$ 9	6
Short-term Debt [Member]
Debt instrument, principal outstanding	$ 309	$ 642