Income Taxes - Effective Income Tax Rate Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Difference Between Income Tax Expense Computed Using Statutory Federal Income Tax Rate And Effective Rate [Abstract]
Statutory federal income tax	$ 15,624	$ 13,757	$ 26,239
State income taxes, less federal income tax benefit	3,607	3,048	6,261
Permanent items	1,131	306	1,496
Change in valuation allowance	(2,659)	2,509	(1,005)
Share-based compensation	426	210	(6,378)
State income tax credits		954	677
Change in uncertain tax position liability			(644)
Prior year tax adjustments	(592)	(464)	(590)
Net impact of foreign operations	(3)	9	(990)
Other	(10)	(18)
Total	$ 17,530	$ 20,293	$ 27,046

Income tax reconciliation change in uncertain tax position liability.

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Income tax reconciliation repatriation of foreign earnings (losses).

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Income Tax Reconciliation Tax Credits Reversal.

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

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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 revisions of previously reported income tax expense (benefit).

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