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Employee Postretirement Benefits - Composition of Periodic Benefit Cost (Details) - USD ($) $ in Thousands | 3 Months Ended
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Mar. 31, 2023 | Mar. 31, 2022
Retirement Benefits [Abstract] |  |
Net Periodic Benefit Cost (Income) | $ (1,724) | $ 1,479
Net Amount Amortized (Deferred) Due to the Effect of Regulation | 408 | 527
Net Periodic Benefit Cost (Income) Recognized | $ (1,316) | $ 2,006

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- Definition Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Net of Deferrals + References No definition available. + Details
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