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v3.23.3

Employee Postretirement Benefits - Components of Net Periodic Benefit Cost (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2023 | Sep. 30, 2022
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Net Periodic Benefit Cost (Income) | $ (1,568) | $ 1,476 | $ (4,700) | $ 4,435
Pension Benefits (Pension Plan) |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Service Cost | 925 | 1,644 | 2,774 | 4,932
Interest Cost | 4,109 | 3,086 | 12,327 | 9,258
Expected Return on Assets | (6,479) | (5,921) | (19,436) | (17,763)
Amortization of Prior Service Cost | 0 | 0 | 0 | 0
Amortization of Net Actuarial Loss | 0 | 1,966 | 0 | 5,899
Net Periodic Benefit Cost (Income) | (1,445) | 775 | (4,335) | 2,326
Pension Benefits (ESSRP) |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Service Cost | 18 | 48 | 54 | 146
Interest Cost | 472 | 335 | 1,417 | 1,006
Expected Return on Assets | 0 | 0 | 0 | 0
Amortization of Prior Service Cost | 0 | 0 | 0 | 0
Amortization of Net Actuarial Loss | 0 | 141 | 0 | 425
Net Periodic Benefit Cost (Income) | 490 | 524 | 1,471 | 1,577
Postretirement Benefits |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Service Cost | 152 | 335 | 458 | 1,004
Interest Cost | 668 | 510 | 2,006 | 1,531
Expected Return on Assets | 0 | 0 | 0 | 0
Amortization of Prior Service Cost | (1,433) | (1,433) | (4,300) | (4,300)
Amortization of Net Actuarial Loss | 0 | 765 | 0 | 2,297
Net Periodic Benefit Cost (Income) | $ (613) | $ 177 | $ (1,836) | $ 532

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