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Pension Plans and Other Postretirement Benefit Plans - Additional Information (Details) - USD ($)	9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024
Defined Benefit Plan Disclosure [Line Items]
Payment for pension benefits	$ 10,000,000	$ 10,000,000
Percentage of service related net periodic benefit costs capitalized to utility property	45.00%
Percentage of service related net periodic benefit costs recorded to operating expenses	55.00%
Percentage of non-service related net periodic benefit costs capitalized to regulatory assets	45.00%
Percentage of non-service related net periodic benefit costs recorded to other expense	55.00%
Pension Plans, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected contributions to pension plan	$ 0

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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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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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