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Benefit Plans - Fair Value of Plan Assets (Details) - USD ($) $ in Thousands | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
--- | --- | --- | ---
Pension Plan |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan Assets at Fair Value | $ 250,674 | $ 391,555 |
Pension Plan | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan Assets at Fair Value | 13,395 | 37,018 |
Pension Plan | Significant Other Observable Inputs (Level 2) |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan Assets at Fair Value | 237,279 | 354,537 |
Pension Plan | Domestic Mutual Funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan Assets at Fair Value | 67 | 4,071 |
Pension Plan | Domestic Mutual Funds | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan Assets at Fair Value | 67 | 4,071 |
Pension Plan | Domestic Mutual Funds | Significant Other Observable Inputs (Level 2) |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan Assets at Fair Value | 0 | 0 |
Pension Plan | U.S. government securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan Assets at Fair Value | 13,328 | 32,947 |
Pension Plan | U.S. government securities | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan Assets at Fair Value | 13,328 | 32,947 |
Pension Plan | U.S. government securities | Significant Other Observable Inputs (Level 2) |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan Assets at Fair Value | 0 | 0 |
Pension Plan | Corporate debt securities and other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan Assets at Fair Value | 146,854 | 221,033 |
Pension Plan | Corporate debt securities and other | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan Assets at Fair Value | 0 | 0 |
Pension Plan | Corporate debt securities and other | Significant Other Observable Inputs (Level 2) |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan Assets at Fair Value | 146,854 | 221,033 |
Pension Plan | Non-government foreign debt securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan Assets at Fair Value | 20,793 | 34,103 |
Pension Plan | Non-government foreign debt securities | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan Assets at Fair Value | 0 | 0 |
Pension Plan | Non-government foreign debt securities | Significant Other Observable Inputs (Level 2) |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan Assets at Fair Value | 20,793 | 34,103 |
Pension Plan | Municipal bonds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan Assets at Fair Value | 18,336 | 20,093 |
Pension Plan | Municipal bonds | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan Assets at Fair Value | 0 | 0 |
Pension Plan | Municipal bonds | Significant Other Observable Inputs (Level 2) |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan Assets at Fair Value | 18,336 | 20,093 |
Pension Plan | Pooled Equity Accounts |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan Assets at Fair Value | 51,296 | 79,308 |
Pension Plan | Pooled Equity Accounts | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan Assets at Fair Value | 0 | 0 |
Pension Plan | Pooled Equity Accounts | Significant Other Observable Inputs (Level 2) |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan Assets at Fair Value | 51,296 | 79,308 |
Other Postretirement Benefit Plan |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan Assets at Fair Value | 111,154 | 140,839 | $ 119,024
Other Postretirement Benefit Plan | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan Assets at Fair Value | 111,154 | 140,839 |
Other Postretirement Benefit Plan | Domestic Mutual Funds | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan Assets at Fair Value | 89,584 | 112,770 |
Other Postretirement Benefit Plan | International Mutual Funds | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan Assets at Fair Value | $ 21,570 | $ 28,069 |

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