Income Taxes - Difference between Benefit from Income Taxes and Amount Computed by Applying Statutory Income Tax Rate to Income Before Taxes (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Benefits from taxes at statutory rate	$ 2,823	$ (4,314)	$ (5,620)
Rate differential	(4,416)	128	3,009
Change in valuation reserves	(546)	22,865	(2,141)
Nondeductible employee compensation	5,249	6,122	5,472
Stock option/RSU windfall (shortfall)	81	(3,262)	(14,342)
ISO disqualifying disposition windfall	(219)	(253)	(2,849)
Research and development credits	(1,170)	(6,225)	(1,607)
Tax return to provision adjustments	(8,372)	(138)	(3,222)
Net Operating Loss Carryback		(2,465)
Cumulative translation adjustment	4,109	(10,852)	2,025
Permanent and other	863	(4,283)	(443)
Tax reserves	5,160	3,422	18,799
Corscianto liquidation			1,727
Long-term debt from royalty-bearing instrument			(644)
Provision for income taxes	$ 3,562	$ 745	$ 164

Income Tax Rate Reconciliation, Cumulative Translation Adjustment, Amount

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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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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 income tax rates.

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