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Pension Plans and Other Postretirement Benefit Plans - Schedule of Fair Value Hierarchy of pension Plan's Assets (Details) - Pension Plan And SERP [Member] - USD ($) $ in Thousands | Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
--- | --- | --- | ---
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | $ 589,983 | $ 540,703 | $ 750,963
Cash Equivalents [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 6,984 | 5,110 |
Fixed Income Securities [Member] | US Government Debt Securities [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 19,293 | 16,732 |
Fixed Income Securities [Member] | Domestic Corporate Debt Securities [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 175,460 | 161,180 |
Fixed Income Securities [Member] | Debt Security, Government, Non-US [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 27,052 | 23,108 |
Fixed Income Securities [Member] | Municipal Bonds [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 13,772 | 13,427 |
Mutual Funds [Member] | U.S Equity Securities [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 169,993 | 154,442 |
Mutual Funds [Member] | International Equity Securities [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 74,749 | 58,933 |
Common/Collective Trusts [Member] | Real Estate [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 25,284 | 30,406 |
Partnership And Closely Held Investments [Member] | International Equity Securities [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 70,652 | 69,792 |
Partnership And Closely Held Investments [Member] | Real Estate [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 6,744 | 7,573 |
Level 1 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 244,742 | 213,375 |
Level 1 [Member] | Mutual Funds [Member] | U.S Equity Securities [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 169,993 | 154,442 |
Level 1 [Member] | Mutual Funds [Member] | International Equity Securities [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 74,749 | 58,933 |
Level 2 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 242,561 | 219,557 |
Level 2 [Member] | Cash Equivalents [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 6,984 | 5,110 |
Level 2 [Member] | Fixed Income Securities [Member] | US Government Debt Securities [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 19,293 | 16,732 |
Level 2 [Member] | Fixed Income Securities [Member] | Domestic Corporate Debt Securities [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 175,460 | 161,180 |
Level 2 [Member] | Fixed Income Securities [Member] | Debt Security, Government, Non-US [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 27,052 | 23,108 |
Level 2 [Member] | Fixed Income Securities [Member] | Municipal Bonds [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | $ 13,772 | $ 13,427 |

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