Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Operating Loss Carryforwards [Line Items]
Effective Income Tax Rate Reconciliation at Federal Statutory Income Tax Rate, Amount	$ 99,549	$ 59,927	$ 38,720
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Depreciation and Amortization, Amount	(23,028)	(22,325)	(22,991)
Income Tax Reconciliation, AFUDC (net)	(3,567)	1,509	(6,095)
Income Tax Reconciliation, Executive Compensation	1,821	1,386	2,440
Income Tax Reconciliation, Treasury Grant	(5,717)	(5,424)	(8,935)
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount	(13,722)	(13,392)	(3,038)
Effective Income Tax Rate Reconciliation, Other Adjustments, Amount	4,362	2,834	1,563
Total income tax expense	$ 59,698	$ 24,515	$ 1,664
Effective Income Tax Rate Reconciliation, Percent	12.60%	8.60%	0.90%
Deferred Tax Assets, Tax Credit Carryforwards, Production		$ 0
Subsidiaries [Member]
Operating Loss Carryforwards [Line Items]
Effective Income Tax Rate Reconciliation at Federal Statutory Income Tax Rate, Amount	$ 119,962	79,868	$ 63,110
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Depreciation and Amortization, Amount	(23,028)	(22,325)	(22,991)
Income Tax Reconciliation, AFUDC (net)	(3,567)	1,509	(6,095)
Income Tax Reconciliation, Executive Compensation	1,821	1,386	2,440
Income Tax Reconciliation, Treasury Grant	(5,717)	(5,424)	(8,935)
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount	(13,722)	(13,392)	(3,038)
Effective Income Tax Rate Reconciliation, Other Adjustments, Amount	4,546	2,637	1,751
Total income tax expense	$ 80,295	$ 44,259	$ 26,242
Effective Income Tax Rate Reconciliation, Percent	14.10%	11.60%	8.70%