Income Taxes - Summary of Effective Income Tax Rate Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Tax expense computed at federal statutory rate	$ 157,856	$ 96,077	$ 64,048
State income tax expense, net of federal benefit	26,441	17,535	9,810
Limitation on executive compensation	14,915	8,102	4,463
Tax expense (benefit) related to an increase (decrease) in unrecognized tax benefits	(4,044)	473	(1,571)
Stock based compensation (windfall)/shortfall	(1,830)	(7,907)	(2,828)
Federal energy credits	(14,558)	(23,331)	(7,649)
Rate changes	81	(291)	190
Change in valuation allowance	(1,054)	(2,128)	121
Other	230	1,400	93
Provision for income taxes	$ 178,037	$ 89,930	$ 66,677
Effective tax rate	23.70%	19.70%	21.90%

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Amount of the difference between reported income tax expense (benefit) and the expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to a limitation on executive compensation.

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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