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v3.24.3

Benefit Plans (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2024 | Mar. 31, 2024 | Sep. 30, 2023 | Sep. 30, 2024 | Sep. 30, 2023
Pension and Supplemental Executive Retirement Plans |  |  |  |  |
Components of Net Periodic Benefit Cost [Abstract] |  |  |  |  |
Company service cost | $ 0 |  | $ 0 | $ 0 | $ 0
Interest cost | 3,247 |  | 3,297 | 9,741 | 10,278
Expected return on plan assets | (3,644) |  | (3,426) | (10,932) | (10,432)
Net actuarial losses (gains) | 522 |  | 529 | 1,568 | 1,656
Prior service cost (credit) | 87 |  | 87 | 259 | 259
Cost of settlements and curtailments | 0 |  | 334 | 0 | 9,181
Net periodic benefit cost (benefit) | 212 |  | 821 | 636 | 10,942
Other Postretirement Benefit Plans |  |  |  |  |
Components of Net Periodic Benefit Cost [Abstract] |  |  |  |  |
Company service cost | 417 |  | 374 | 1,251 | 1,122
Interest cost | 376 |  | 409 | 1,126 | 1,225
Expected return on plan assets | (2,493) |  | (2,059) | (7,481) | (6,176)
Net actuarial losses (gains) | (382) |  | (38) | (1,142) | (113)
Prior service cost (credit) | 454 |  | 465 | 1,360 | 1,396
Cost of settlements and curtailments | 0 |  | 0 | 0 | 0
Net periodic benefit cost (benefit) | $ (1,628) |  | $ (849) | $ (4,886) | $ (2,546)
Pension Plan |  |  |  |  |
Components of Net Periodic Benefit Cost [Abstract] |  |  |  |  |
Company contribution to qualified pension plan |  | $ 23,000 |  |  |

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