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Employee Postretirement Benefits - Schedule of Allocation of Plan Assets (Details) - USD ($) $ in Thousands | Dec. 31, 2024 | Dec. 31, 2023
--- | --- | ---
Defined Benefit Plan Disclosure [Line Items] |  |
Plan Assets | $ 327,275 | $ 330,479
Level 1 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Plan Assets | 326,214 | 328,961
Level 2 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Plan Assets | 0 | 0
Level 3 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Plan Assets | 0 | 0
NAV |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Plan Assets | 1,061 | 1,518
Equity Funds |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Plan Assets | 116,889 | 127,159
Equity Funds | Level 1 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Plan Assets | 116,889 | 127,159
Equity Funds | Level 2 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Plan Assets | 0 | 0
Equity Funds | Level 3 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Plan Assets | 0 | 0
Equity Funds | NAV |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Plan Assets | 0 | 0
Fixed Income Funds |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Plan Assets | 175,310 | 167,604
Fixed Income Funds | Level 1 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Plan Assets | 175,310 | 167,604
Fixed Income Funds | Level 2 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Plan Assets | 0 | 0
Fixed Income Funds | Level 3 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Plan Assets | 0 | 0
Fixed Income Funds | NAV |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Plan Assets | 0 | 0
Hybrid Funds |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Plan Assets | 10,106 | 10,980
Hybrid Funds | Level 1 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Plan Assets | 10,106 | 10,980
Hybrid Funds | Level 2 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Plan Assets | 0 | 0
Hybrid Funds | Level 3 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Plan Assets | 0 | 0
Hybrid Funds | NAV |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Plan Assets | 0 | 0
U.S. Treasury Securities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Plan Assets | 23,909 | 23,218
U.S. Treasury Securities | Level 1 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Plan Assets | 23,909 | 23,218
U.S. Treasury Securities | Level 2 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Plan Assets | 0 | 0
U.S. Treasury Securities | Level 3 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Plan Assets | 0 | 0
U.S. Treasury Securities | NAV |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Plan Assets | 0 | 0
SEI Energy Debt Collective Fund |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Plan Assets | 1,061 | 1,518
SEI Energy Debt Collective Fund | Level 1 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Plan Assets | 0 | 0
SEI Energy Debt Collective Fund | Level 2 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Plan Assets | 0 | 0
SEI Energy Debt Collective Fund | Level 3 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Plan Assets | 0 | 0
SEI Energy Debt Collective Fund | NAV |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Plan Assets | $ 1,061 | $ 1,518

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