Income Taxes - Income Tax Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income Tax Disclosure [Abstract]
Income tax expense at statutory rates	$ 36,775	$ 28,205	$ 22,995
Increase (reduction) from:
Jurisdictional rate differences	2,766	1,989	1,599
Executive compensation limitations	183	481	1,314
Valuation allowance	(789)	(316)	(269)
Stock based compensation	(24)	122	(322)
U.S. state taxes	6,076	2,632	3,724
Foreign tax (credit) / expense	(371)	267	0
R&D credit (net)	(3,618)	(1,585)	(782)
Other credits	(628)	0	0
GILTI	109	500	0
FDII	(731)	(192)	0
Previously unrecognized tax (benefit) / expense	170	51	8
Other (net)	(959)	228	986
Provision for income tax	$ 38,959	$ 32,382	$ 29,253
Effective tax rate (percent)	22.20%	24.10%	26.70%

Effective Income Tax Rate Reconciliation, Executive Compensation Limitation, Amount

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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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