Income Taxes - Reconciliation of Federal Statutory Income Tax Rate to Company's Effective Tax Rate (Details)	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Federal statutory income tax rate	21.00%	21.00%
State income taxes, net of federal tax effect	6.30%	0.80%
Change in uncertain tax benefits	(0.60%)	(8.00%)
Stock based compensation – restricted stock	2.00%	(7.50%)
Return to provision adjustment	(0.70%)	4.80%
Permanent differences	1.10%	(9.80%)
Tax credits	(2.70%)	10.80%
CARES Act carryback	(0.094)	0
Other	0.00%	1.60%
Effective tax rate	17.00%	13.70%

Effective Income Tax Rate Reconciliation, CARES Act, Net Operating Loss Carryback, Percent

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Percentage of the effective income tax rate reconciliation expenses income from tax credits.

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Effective income tax rate reconciliation, return to provision adjustment.

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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 income tax rates.

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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 expense for award under share-based payment arrangement. Excludes expense determined to be nondeductible upon grant or after for award under share-based payment arrangement.

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