Reconciliation of Income Taxes Computed at U.S. Federal Statutory Rate to Income Taxes (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Income tax expense (benefit) at statutory rate	$ (5,623)	$ 17,101	$ 31,377
Excess compensation	1,786	1,753
State income taxes	(2,189)	1,248	5,011
Effect of federal rate change			(36,768)
Stock-based compensation	145	(15,924)	(7,072)
Research and development tax credit	(2,995)	(1,470)	(800)
Uncertain tax position	67	(545)	(55)
Foreign rate differential	(18)	(57)	(203)
Meals and entertainment	659	292	286
Unremitted earnings tax			363
All other	(42)	554	(1,474)
Total income tax (benefit) expense	$ (8,210)	$ 2,952	$ (9,335)

Income tax reconciliation excess compensation.

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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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