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v3.25.1

Retirement Benefit Plans - Narrative (Details) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2025 USD ($) | Dec. 31, 2024 USD ($) | Dec. 31, 2023 USD ($)
Defined Benefit Plan Disclosure [Line Items] |  |  |
Interest credit under cash balance plan | 0.03 |  |
Employer matching contribution, percent of match, maximum | 5.00% |  |
Employees' Pension Plan |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Assumptions used calculating benefit obligation, interest rate to annuitize cash balance account |  | 4.66% |
Defined benefit plan, increase in benefit payable (in percent) | 3.00% |  |
Defined benefit plan, benefit obligation, increase (decrease) for plan amendment | $ 352 |  |
Defined benefit plan, amortization of service cost (in years) | 9 years 8 months 12 days | 7 years 7 months 20 days |
Defined benefit plan, benefit obligation, period increase (decrease) |  |  | $ 526
Select Executive Retirement Plan |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Assumptions used calculating benefit obligation, interest rate to annuitize cash balance account |  | 5.25% |
Defined benefit plan, amortization of service cost (in years) | 12 years 6 months | 7 years 7 months 20 days |
Defined benefit plan, benefit obligation, period increase (decrease) | $ 123 | $ 441 |
Postretirement Benefit Plans |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Assumptions used calculating benefit obligation, interest rate to annuitize cash balance account |  | 5.57% |
On or Subsequent to January 1, 2003 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Service credits, percent of eligible salaries | 6.00% |  |
Prior to January 1, 2003 | Minimum |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Service credits, percent of eligible salaries | 6.00% |  |
Prior to January 1, 2003 | Maximum |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Service credits, percent of eligible salaries | 12.00% |  |

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- Definition Amount of increase (decrease) in benefit obligation of defined benefit plan from change in terms of existing plan or initiation of new plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (a)(7) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + Details
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