Income Taxes - Effective Income Tax Rate Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Statutory federal rate	21.00%	21.00%	21.00%
Computed federal income tax expense (benefit) at applicable statutory rate of 21%	$ 11,323	$ (2,778)	$ 461
State income tax benefit	(283)	(1,448)	(2,241)
Tax credits	(2,507)	(2,391)	(1,064)
Tax effect of international items	(281)	4,705	1,325
Uncertain tax positions	401	(455)	(574)
Deferred compensation insurance assets	(413)	(290)	(493)
Stock-based compensation	(5,571)	(1,822)	(1,659)
Valuation allowance		1,257
DOJ Settlement		1,890
Remeasurement of state deferred taxes	(526)	(1,765)
Non-deductible expenses	2,455	1,077	1,320
Remeasurement of contingent consideration liabilities	733	(1,185)	(87)
Other - including the effect of graduated rates	132	(183)	(246)
Total income tax expense (benefit)	$ 5,463	$ (3,388)	$ (3,258)

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

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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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