Income Taxes (Schedule of Components of Income Tax Expense by Expense) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income Taxes [Abstract]
Federal statutory income tax expense	$ 73,652	$ 142,149	$ 134,636
State income tax expense, net of federal income tax expense benefit	12,966	26,284	24,123
Executive compensation	9,507	5,889	3,520
Excess tax benefits upon vesting of share based payment awards	(311)	(675)	(764)
Federal energy credits	(2,596)	(18,324)	(16,451)
State tax credits	(185)	(635)	(1,220)
Other	(1,427)	(2,914)	(1,226)
Income tax expense	$ 91,606	$ 151,774	$ 142,618