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Pension Plans and Other Postretirement Benefit Plans - Additional Information (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Defined Benefit Plan Disclosure [Line Items]
Payment for pension benefits		$ 42,000	$ 42,000	$ 22,000
Settlement loss		$ 11,800
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%
Deferred Compensation, Excluding Share-based Payments and Retirement Benefits [Member] | Executive Officer [Member]
Defined Benefit Plan Disclosure [Line Items]
Deferred compensation, earlier of retirement, termination, disability or death, percent		75.00%
Deferred compensation incentive payments, percent		100.00%
Equity Securities
Defined Benefit Plan Disclosure [Line Items]
Target investment allocation		55.00%	55.00%
Debt Securities
Defined Benefit Plan Disclosure [Line Items]
Target investment allocation		40.00%	40.00%
Real Estate [Member]
Defined Benefit Plan Disclosure [Line Items]
Target investment allocation		5.00%	5.00%
Absolute Return [Member]
Defined Benefit Plan Disclosure [Line Items]
Target investment allocation		0.00%	0.00%
Pension Plans, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected contributions to pension plan		$ 10,000
Settlement loss	[1]	11,828
Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected contributions to pension plan		$ 7,000
Other Postretirement Benefits [Member] | Equity Securities
Defined Benefit Plan Disclosure [Line Items]
Target investment allocation		60.00%	60.00%
Other Postretirement Benefits [Member] | Debt Securities
Defined Benefit Plan Disclosure [Line Items]
Target investment allocation		40.00%	40.00%
[1] The settlement loss was deferred as a regulatory asset to be amortized over future periods.

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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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Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

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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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