Annual report pursuant to Section 13 and 15(d)

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

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Postretirement Health Care and Life Insurance Benefits Postretirement Health Care and Life Insurance Benefits (Estimated Postretirement Benefit Payments in Future Years) (Details) - Other Postretirement Benefits Plan [Member]
$ in Millions
Feb. 01, 2020
USD ($)
Expected Benefit [Abstract]  
2020 $ 14
2021 13
2022 12
2023 11
2024 10
2025-2029 41
Expected Federal Subsidy [Abstract]  
2020 0
2021 0
2022 0
2023 0
2024 0
2025-2029 $ 1