v3.22.1

Pension and Other Postretirement Benefits - Narrative (Details) - Pension benefits - UNITED STATES $ in Millions | 1 Months Ended |
--- | --- | ---
Jan. 31, 2022 plan | Jan. 31, 2021 USD ($) plan | Mar. 31, 2022 USD ($)
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined Benefit Plan, Number Of Pension Plans | plan | 2 | 2 |
Defined Benefit Plan, Plan Assets, Contributions by Employer |  | $ 200 |
Defined Benefit Plan, Funded Plan |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined Benefit Plan, Minimum Required Employer Contributions, Next Fiscal Year |  | 183 | $ 22
Defined Benefit Plan, Employer Contribution, Additional Contribution Above Minimum Requirement |  | $ 17 |

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