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Benefit Plans (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2026 | Jun. 30, 2025 | Jun. 30, 2026 | Jun. 30, 2025
Pension and Supplemental Executive Retirement Plans |  |  |  |
Components of Net Periodic Benefit Cost [Abstract] |  |  |  |
Company service cost (1) | $ 500 | $ 0 | $ 1,000 | $ 0
Interest cost | 3,013 | 3,297 | 6,026 | 6,596
Expected return on plan assets | (3,079) | (3,442) | (6,157) | (6,884)
Net actuarial losses (gains) | 948 | 546 | 1,895 | 1,092
Prior service cost (credit) | 87 | 87 | 173 | 173
Cost of settlements and curtailments | 0 | 3,680 | 0 | 3,680
Net periodic benefit cost (benefit) | 1,469 | 4,168 | 2,937 | 4,657
Other Postretirement Benefit Plans |  |  |  |
Components of Net Periodic Benefit Cost [Abstract] |  |  |  |
Company service cost (1) | 209 | 235 | 418 | 469
Interest cost | 283 | 311 | 566 | 622
Expected return on plan assets | (3,395) | (2,911) | (6,789) | (5,822)
Net actuarial losses (gains) | (962) | (693) | (1,923) | (1,385)
Prior service cost (credit) | 119 | 117 | 236 | 235
Cost of settlements and curtailments | 0 | 0 | 0 | 0
Net periodic benefit cost (benefit) | $ (3,746) | $ (2,941) | $ (7,492) | $ (5,881)

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- Definition Amount of prior service cost (credit) recognized in net periodic benefit cost (credit) of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 17 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480482/715-20-55-17 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 3A -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480535/715-20-45-3A Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 18 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480482/715-20-55-18 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (h)(5) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (a)(5) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-6 + Details
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