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Employee Postretirement Benefits - Narrative (Details) $ in Thousands | 1 Months Ended | 12 Months Ended
--- | --- | ---
Feb. 28, 2022 USD ($) | Dec. 31, 2021 USD ($) year | Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($)
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Payment for pension benefits |  | $ 10,000 | $ 11,200 | $ 22,500
Defined contribution plan, cost |  | $ 6,500 | 5,300 | $ 5,300
Subsequent Event |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Payment for pension benefits | $ 20,000 |  |  |
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 |  | $ 378,300 | $ 385,300 |
Decrease in funded status of plan |  | $ 38,200 |  |
Discount rate (as a percent) |  | 3.03% | 2.78% |
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 |  |
Discount rate (as a percent) |  | 3.01% | 2.75% |
Executive Survivor and Supplemental Retirement Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Accumulated benefit obligation |  | $ 46,800 | $ 47,700 |
Discount rate (as a percent) |  | 2.93% | 2.61% |

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- Definition Amount of actuarial present value of benefits attributed to employee service rendered, excluding assumptions about future compensation level. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 + Details
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