Benefits of the tax holiday per share.

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Benefits of the tax holiday.

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Deferred Tax Additions Reductions Recorded In Provision for Income Taxes.

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Represents income tax reconciliation nondeductible expense executive compensation.

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Income Taxes [Line Items].

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Tax credit carry forward expiration year end.

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

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Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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Income Taxes - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Taxes [Line Items]
U.S. Federal income tax statutory rate	21.00%	21.00%	35.00%
Additional deferred tax provision		$ 2,614	$ 22,345
Gross tax research other tax credit carryforwards		64,983
Accrued interest on unrecognized tax benefits		527	568	$ 327
Gross unrecognized tax benefits excluding interest and penalties	$ 43,493	32,684	27,345	$ 25,465
Net unrecognized tax benefits, excluding interest and penalties, related to foreign tax positions		1,463
Change in valuation allowance	9,424	4,307	$ 1,102
Income tax reconciliation nondeductible expense executive compensation	$ 5,023
Benefits Of The Tax Holi day Per Share	$ 0.04
Inland Revenue, Singapore (IRAS) [Member]
Income Taxes [Line Items]
Benefits of the tax holiday	$ 2,200
Maximum [Member]
Income Taxes [Line Items]
U.S. Federal income tax statutory rate	2.80%
Indefinite [Member]
Income Taxes [Line Items]
Gross tax research other tax credit carryforwards		$ 14,230
Federal State and Foreign [Member]
Income Taxes [Line Items]
Tax credit expiration period		2037
Federal State and Foreign [Member] \| Indefinite [Member]
Income Taxes [Line Items]
Operating loss carry forwards		$ 57,588
Federal State and Foreign [Member] \| 2017 [Member]
Income Taxes [Line Items]
Operating loss carry forwards		$ 98,280