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Post Retirement Benefits - Narrative (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2011
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Net period benefit cost reduction |  | $ 496 | $ 496 | $ 496 |
Defined Benefit Plan, Net Periodic Benefit Cost Credit, Immediate Recognition of Actuarial Gain Loss, Statement of Income or Comprehensive Income, Extensible List Not Disclosed Flag |  | Consolidated Balance Sheets |  |  |
Actuarial gain (loss) |  | $ 2,272 | 108 |  |
Post Retirement Benefits |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Reduction of post retirement benefit liability |  |  |  |  | $ (10,282)
Net period benefit cost reduction |  | 496 | 496 | $ 496 |
Net actuarial gain (loss) |  | 2,136 | (79) |  |
Actuarial gain (loss) |  | (136) | (187) |  |
Net credit of amounts net yet recognized as a component of net periodic benefit costs |  | 3,174 | (1,361) |  |
Gain (loss) of net periodic post retirement costs |  | 496 | (22) |  |
Interest expense related to post retirement healthcare |  | $ 265 | $ 209 |  |
Weighted average rate of increase in per capita cost of covered health care benefits |  | 5.80% | 5.40% |  |
Post Retirement Benefits | Medical, Pre Age 65 |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Weighted average rate per capita cost of covered health care benefits |  | 5.00% | 5.40% |  |
Post Retirement Benefits | Medical, Post Age 65 |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Weighted average rate per capita cost of covered health care benefits |  | 4.25% | 4.25% |  |
Post Retirement Benefits | Drugs |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Weighted average rate per capita cost of covered health care benefits |  | 5.00% | 5.00% |  |
Forecast | Post Retirement Benefits |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Net period benefit cost reduction | $ 496 |  |  |  |

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- Definition Amount of increase (decrease) in accumulated benefit obligation from change in existing term of defined benefit plan or initiation of new defined benefit plan. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (r) -URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 + Details
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- Definition Amount of gain (loss) from change in actuarial assumptions which (increases) decreases benefit obligation of defined benefit plan. Assumptions include, but are not limited to, interest, mortality, employee turnover, salary, and temporary deviation from substantive plan. + 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 (a)(4) -URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 + Details
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- Definition Amount of gain (loss), recognized immediately as component of net periodic benefit (cost) credit, for change in value of benefit obligation or plan assets from experience different from that assumed, change in actuarial assumption, or consequence of temporarily deviating from substantive plan. Includes, but is not limited to, amount in excess of 10 percent of greater of fair value of plan assets or benefit obligation. + 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 (h)(4) -URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 6 -Subparagraph (a)(4) -URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e2709-114920 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 45 -Paragraph 3A -Subparagraph (b) -URI https://asc.fasb.org/extlink&oid=123453770&loc=SL108413299-114919 + Details
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- Definition Amount of cost (credit) included in accumulated other comprehensive (income) loss expected to be recognized in net periodic benefit cost (credit) for fiscal year following most recent annual statement of financial position. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 + Details
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