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Pension Plans and Other Postretirement Benefit Plans - Additional Information (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended		9 Months Ended
	Apr. 30, 2024	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Defined Benefit Plan Disclosure [Line Items]
Payment for pension benefits				$ 10,000	$ 10,000
Percentage of service related net periodic benefit costs capitalized to utility property				40.00%
Percentage of service related net periodic benefit costs recorded to operating expenses				60.00%
Percentage of non-service related net periodic benefit costs capitalized to regulatory assets				40.00%
Percentage of non-service related net periodic benefit costs recorded to other expense				60.00%
Curtailment associated gain (loss)	$ 1,400
Pension Plans, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected contributions to pension plan		$ 0		$ 0
Curtailment associated gain (loss)				(169)
Loss on acceleration of unrecognized priof service costs		$ 126	$ 123	$ 375	$ 369

X

- Definition

Percentage of non-service related net periodic benefit costs capitalized to regulatory assets.

+ References

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- Definition

Percentage of non-service related net periodic benefit costs recorded to other expense.

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- Definition

Percentage of service related net periodic benefit costs capitalized to utility property.

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- Definition

Percentage of service related net periodic benefit costs recorded to operating expenses.

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- Definition

Amount of prior service cost (credit) recognized in net periodic benefit cost (credit) of defined benefit plan.

+ References

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of contribution expected to be received by defined benefit plan from employer in next fiscal year following current fiscal year.

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- Definition

Amount of gain (loss) recognized in net periodic benefit (cost) credit from event reducing expected years of future service of present employees or eliminating accrual of defined benefits for some or all future services of present employees.

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- Definition

Amount of cash outflow for pension benefit. Includes, but is not limited to, employer contribution to fund plan asset and payment to retiree. Excludes other postretirement benefit.

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