Annual report pursuant to Section 13 and 15(d)

Postretirement Health Care and Life Insurance Benefits (Estimated Postretirement Benefit Payments In Future Years) (Details)

v3.7.0.1
Postretirement Health Care and Life Insurance Benefits (Estimated Postretirement Benefit Payments In Future Years) (Details) - Other Postretirement Benefit Plan [Member]
$ in Millions
Jan. 28, 2017
USD ($)
Expected Benefit  
2017 $ 17
2018 17
2019 16
2020 16
2021 15
2022-2026 63
Expected Federal Subsidy  
2017 1
2018 1
2019 1
2020 0
2021 0
2022-2026 $ 1