Pension Plans and Other Postretirement Benefit Plans - Additional Information (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Defined Benefit Plan Disclosure [Line Items]
Payment for pension benefits		$ 10,000	$ 42,000	$ 42,000
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%
Partial Settlement of Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Regulatory asset amortization period			12 years
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%
Pension Plans, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected contributions to pension plan		$ 10,000
Settlement loss	[1]		$ 11,828
Fair value of plan assets		589,983	540,703	750,963
Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected contributions to pension plan		7,100
Fair value of plan assets		$ 58,126	$ 49,472	$ 59,544
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%
Other Postretirement Benefits [Member] | Balanced Mutual Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		$ 58,100	$ 49,500

[1] The settlement loss was deferred as a regulatory asset and is being amortized over 12 years in accordance with regulatory accounting orders.