Income Taxes - Income Tax Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Income tax expense at statutory rates	$ 22,995	$ 16,749	$ 17,765
Increase (reduction) from:
Jurisdictional rate differences	1,599	1,034	988
Executive compensation limitation	1,314	170	715
Stock based compensation	(322)	(366)	(358)
U.S. state taxes	3,724	2,556	3,137
Foreign tax expense	0	704	0
R&D credit	(670)	(415)	(699)
GILTI	0	50	872
Previously unrecognized tax (benefit)/expense	8	2,219	(1,504)
Other, net	605	(748)	580
Provision for income taxes	$ 29,253	$ 21,953	$ 21,496
Effective tax rate	27.00%	28.00%	25.00%

Effective Income Tax Rate Reconciliation, Before Tax Cuts And Jobs Act Of 2017, Percent

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Effective Income Tax Rate Reconciliation, Executive Compensation Limitation, Amount

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Effective Income Tax Rate Reconciliation, Global Intangible Low-Taxed Income, Amount

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Effective Income Tax Rate Reconciliation, Previously Unrecognized Tax Benefit, Amount

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Income Tax Expense (Benefit), Before Tax Cuts And Jobs Act Of 2017

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Income Tax Rate Reconciliation, Foreign Tax Expense

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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 foreign income tax expense (benefit).

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
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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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32687-109319

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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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