v3.22.4

Pension and Other Postretirement Benefits - Expected Benefit Payments (Details) $ in Millions	1 Months Ended	3 Months Ended	12 Months Ended
	Apr. 30, 2021 USD ($) plan	Jun. 30, 2021 plan	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Pension benefits​
Pension benefits and Net other postretirement benefits
2023			$ 142
2024			142
2025			143
2026			146
2027			145
2028 through 2032			719
Expected benefit payments			1,437
Other postretirement benefits
Contributions by employer			31	$ 458
Pension benefits​ | United States
Other postretirement benefits
Contributions by employer	$ 250
Number of defined benefit pension plans | plan	2	2
Other postretirement benefits
Pension benefits and Net other postretirement benefits
2023			27
2024			27
2025			27
2026			27
2027			26
2028 through 2032			127
Expected benefit payments			261
Other postretirement benefits
Contributions by employer			$ 0	$ 0

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