Amortization period of leasehold improvements.

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Maximum maturity period of liquid investments.

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Maximum period of company's research and development projects.

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Minimum investment maturity period.

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Minimum Percentage Of Recognized Tax Benefits From Uncertain Tax Position

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Minimum period of company's research and development projects.

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Number of customer related to credit concentration risk of net sales.

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Schedule Of Significant Accounting Policies [Line Items]

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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount before tax of foreign currency transaction realized gain (loss) recognized in the income statement.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset.

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Summary of Significant Accounting Policies - Additional Information (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017 USD ($) Customer	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Schedule Of Significant Accounting Policies [Line Items]
Minimum period of company's research and development projects		3 months
Maximum period of company's research and development projects		30 months
Vesting period		3 years
Maximum maturity period of liquid investments		3 years
Maturity dates for short-term investments		12 months
Amortization period of leasehold improvements		Shorter of the lease term or the estimated useful life of the leased asset.
Asset impairment charge		$ 6,719	$ 5,000
Increase (decrease) in valuation allowance on state tax credit carryforwards		1,102	6,400	$ (20,636)
Valuation allowance		$ 13,629	$ 12,527	$ 6,127
Minimum percentage of recognition of tax benefits from uncertain tax positions		50.00%
U.S. federal corporate income tax rate		35.00%	35.00%	35.00%
Other Expense [Member]
Schedule Of Significant Accounting Policies [Line Items]
Net foreign exchange losses from re-measurement		$ (6,132)	$ (2,823)
Selling, General and Administrative Expenses [Member]
Schedule Of Significant Accounting Policies [Line Items]
Net foreign exchange losses from re-measurement				$ (1,388)
Customer Concentration Risk [Member] \| Accounts Receivable [Member]
Schedule Of Significant Accounting Policies [Line Items]
Number of customers comprising of Accounts Receivable \| Customer		1
Customer Concentration Risk [Member] \| Customer A [Member] \| Sales Revenue, Net [Member]
Schedule Of Significant Accounting Policies [Line Items]
Concentration risk, percentage		13.00%	14.00%	18.00%
Customer Concentration Risk [Member] \| Customer B [Member] \| Sales Revenue, Net [Member]
Schedule Of Significant Accounting Policies [Line Items]
Concentration risk, percentage		12.00%	11.00%	13.00%
Customer Concentration Risk [Member] \| Semiconductor Products [Member] \| Sales Revenue, Net [Member]
Schedule Of Significant Accounting Policies [Line Items]
Concentration risk, percentage		57.00%	56.00%	69.00%
Scenario, Forecast [Member]
Schedule Of Significant Accounting Policies [Line Items]
U.S. federal corporate income tax rate	21.00%
Minimum [Member]
Schedule Of Significant Accounting Policies [Line Items]
Intangible assets amortized period		1 year
Minimum [Member] \| Credit Concentration Risk [Member] \| Accounts Receivable [Member]
Schedule Of Significant Accounting Policies [Line Items]
Concentration risk, percentage		10.00%
Minimum [Member] \| Buildings [Member]
Schedule Of Significant Accounting Policies [Line Items]
Estimated useful lives		20 years
Minimum [Member] \| Machinery and Equipment [Member]
Schedule Of Significant Accounting Policies [Line Items]
Estimated useful lives		3 years
Minimum [Member] \| Furniture and Fixtures [Member]
Schedule Of Significant Accounting Policies [Line Items]
Estimated useful lives		3 years
Minimum [Member] \| Office Equipment [Member]
Schedule Of Significant Accounting Policies [Line Items]
Estimated useful lives		3 years
Maximum [Member]
Schedule Of Significant Accounting Policies [Line Items]
Intangible assets amortized period		18 years
Maximum [Member] \| Buildings [Member]
Schedule Of Significant Accounting Policies [Line Items]
Estimated useful lives		31 years 6 months
Maximum [Member] \| Machinery and Equipment [Member]
Schedule Of Significant Accounting Policies [Line Items]
Estimated useful lives		10 years
Maximum [Member] \| Furniture and Fixtures [Member]
Schedule Of Significant Accounting Policies [Line Items]
Estimated useful lives		10 years
Maximum [Member] \| Office Equipment [Member]
Schedule Of Significant Accounting Policies [Line Items]
Estimated useful lives		10 years