v3.22.0.1

Pension and Other Postretirement Benefits - Expected Benefit Payments (Details) $ in Millions | 1 Months Ended | 3 Months Ended | 12 Months Ended
--- | --- | --- | ---
Apr. 30, 2021 USD ($) plan | Jun. 30, 2021 plan | Dec. 31, 2021 USD ($) | Dec. 31, 2020 USD ($)
Pension benefits​ |  |  |  |
Pension benefits and Net other postretirement benefits |  |  |  |
2022 |  |  | $ 164 |
2023 |  |  | 162 |
2024 |  |  | 160 |
2025 |  |  | 158 |
2026 |  |  | 158 |
2027 through 2031 |  |  | 763 |
Expected benefit payments |  |  | 1,565 |
Other postretirement benefits |  |  |  |
Contributions by employer |  |  | 458 | $ 271
Pension benefits​ | United States |  |  |  |
Other postretirement benefits |  |  |  |
Contributions by employer | $ 250 |  |  |
Number of defined benefit pension plans | plan | 2 | 2 |  |
Other postretirement benefits |  |  |  |
Other postretirement benefits |  |  |  |
2022 |  |  | 29 |
2023 |  |  | 28 |
2024 |  |  | 27 |
2025 |  |  | 27 |
2026 |  |  | 27 |
2027 through 2031 |  |  | 128 |
Expected benefit payments |  |  | 266 |
Contributions by employer |  |  | $ 0 | $ 0

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