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Employee Postretirement Benefits - Narrative (Details) $ in Thousands | 12 Months Ended
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Dec. 31, 2022 USD ($) year | Dec. 31, 2021 USD ($) | Dec. 31, 2020 USD ($)
Defined Benefit Plan Disclosure [Line Items] |  |  |
Payment for pension benefits | $ 20,000 | $ 10,000 | $ 11,200
Defined contribution plan, cost | $ 6,700 | 6,500 | $ 5,300
Pension Benefits (Pension Plan) |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Age for compensation | year | 65 |  |
Age below which compensation is reduced | year | 62 |  |
Vesting period | 5 years |  |
Investment redemption, notice period | 95 days |  |
Accumulated benefit obligation | $ 283,200 | 378,300 |
Decrease in benefit obligation for change in discount rate | $ 117,100 | 15,700 |
Increase in benefit obligation for change in expected future compensation |  | $ 6,800 |
Discount rate (as a percent) | 5.51% | 3.03% |
Other Postretirement Benefits Plan |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Health insurance benefits, requisite age | 55 years |  |
Health insurance benefits, requisite service period | 10 years |  |
Decrease in benefit obligation for change in discount rate | $ 17,900 | $ 2,600 |
Increase in benefit obligation for change in expected healthcare cost trends | $ 2,400 |  |
Discount rate (as a percent) | 5.52% | 3.01% |
Executive Survivor and Supplemental Retirement Plan |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Accumulated benefit obligation | $ 35,600 | $ 46,800 |
Decrease in benefit obligation for change in discount rate | $ 10,200 | $ 1,700 |
Discount rate (as a percent) | 5.51% | 2.93% |

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