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Retirement Plans - Narrative (Details) - Pension Plan - USD ($) $ in Millions | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2023 | Dec. 31, 2022
Qualified Plan |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Estimated social security benefits age | 65 years |
Nonqualified Plan |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Pension plan contribution |  | $ 5
Defined benefit plan, expected future employer contributions, current fiscal year | $ 5 |

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