Pension and Other Postemployment Benefits (Details 7) $ in Millions	Dec. 31, 2018 USD ($)
Pension
Estimated Future Benefit Payments
2019	$ 509
2020	533
2021	554
2022	566
2023	580
2024-2028	3,047
OPEB
Estimated Future Benefit Payments
2019	57
2020	48
2021	48
2022	47
2023	46
2024-2028	213
Subsidy Receipts
2019	(1)
2020	(1)
2021	(1)
2022	(1)
2023	(1)
Years 2024-2028	$ (3)

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