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Benefit Plans and Other Postretirement Benefits, Projected Benefit Payments (Details) $ in Millions | Dec. 31, 2018 USD ($)
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Pension Plan [Member] |
Defined Benefit Plan, Gross Projected Benefit Payments [Abstract] |
2019 | $ 281
2020 | 260
2021 | 259
2022 | 260
2023 | 259
2024-2028 | 1,238
Other Postretirement Benefits Plan [Member] |
Defined Benefit Plan, Gross Projected Benefit Payments [Abstract] |
2019 | 45
2020 | 45
2021 | 45
2022 | 44
2023 | 43
2024-2028 | 197
Expected Medicare Part D Subsidies [Abstract] |
2019 | 2
2020 | 2
2021 | 2
2022 | 2
2023 | 2
2024-2028 | 13
Defined Benefit Plan, Net Projected Benefit Payments [Abstract] |
2019 | 43
2020 | 43
2021 | 43
2022 | 42
2023 | 41
2024-2028 | $ 184

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