Income Taxes - Schedule of Reconciliation between Statutory Income Tax Rate and Company's Effective Income Tax Provision (Benefit) Rate (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Effective Income Tax Rate Reconciliation, Amount [Abstract]
Income tax at federal statutory rates	$ (71,998)	$ 27,091	$ 13,167
State taxes, net of federal benefit	(15,816)	7,645	4,640
Equity-based compensation	(485)	(1,776)	668
Tax credits	(304)	(795)	(1,221)
Impact of state rate changes	(3,906)	3,770	(379)
Nondeductible settlement			840
Other	1,583	1,138	200
Total income tax (benefit) provision	$ (30,525)	$ 39,528	$ 17,915
Effective Income Tax Rate Reconciliation, Percent [Abstract]
Income tax at federal statutory rates	21.00%	21.00%	21.00%
State taxes, net of federal benefit	4.61%	5.93%	7.40%
Equity-based compensation	0.14%	(1.38%)	1.07%
Tax credits	0.09%	(0.62%)	(1.95%)
Impact of state rate changes	1.14%	2.92%	(0.60%)
Nondeductible settlement			1.34%
Other	(0.46%)	0.89%	0.31%
Income tax provision (benefit) rate	8.90%	30.64%	28.57%
State [Member]
Effective Income Tax Rate Reconciliation, Amount [Abstract]
Valuation allowance	$ 10,450	$ 2,455
Effective Income Tax Rate Reconciliation, Percent [Abstract]
Valuation allowance	(3.05%)	1.90%
Federal [Member]
Effective Income Tax Rate Reconciliation, Amount [Abstract]
Valuation allowance	$ 49,951
Effective Income Tax Rate Reconciliation, Percent [Abstract]
Valuation allowance	(14.57%)

Effective income tax rate reconciliation impact of state rate changes percent.

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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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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to changes in the valuation allowance for deferred tax assets.

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Percentage of difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to nondeductible expense for share-based payment arrangement.

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations applicable to state and local income tax expense (benefit), net of federal tax expense (benefit).

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to tax credits. Including, but not limited to, research credit, foreign tax credit, investment tax credit, and other tax credits.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to increase (decrease) in the valuation allowance for deferred tax assets.

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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Amount of reported income tax expense (benefit) in excess of (less than) expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to nondeductible expense for award under share-based payment arrangement. Includes, but is not limited to, expense determined to be nondeductible upon grant or after for award under share-based payment arrangement.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to tax credits. Including, but not limited to, research credit, foreign tax credit, investment tax credit, and other tax credits.

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