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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- Definition

Minimum Percentage Of Recognized Tax Benefits From Uncertain Tax Position

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No definition available.

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- Definition

Minimum period of company's research and development projects.

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No definition available.

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- Definition

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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- Definition

Amount charged to advertising expense for the period, which are expenses incurred with the objective of increasing revenue for a specified brand, product or product line.

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

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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- Definition

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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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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No definition available.

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

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- Definition

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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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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- Definition

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, 2016 USD ($) Customer	Dec. 31, 2015 USD ($)	Dec. 31, 2014 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
Advertising costs incurred	$ 1,137
Vesting period	3 years
Maximum maturity period of liquid investments	3 years
Amortization period of leasehold improvements	Shorter of the lease term or the estimated useful life of the leased asset.
Goodwill Impairment		$ 0
Increase (decrease) in valuation allowance on state tax credit carryforwards	$ 6,400	(20,636)	$ (339)
Valuation allowance	$ 12,527	6,127	26,763
Minimum percentage of recognition of tax benefits from uncertain tax positions	50.00%
Other Expense [Member]
Schedule Of Significant Accounting Policies [Line Items]
Net foreign exchange losses from re-measurement	$ (2,823)
Selling, General and Administrative Expenses [Member]
Schedule Of Significant Accounting Policies [Line Items]
Net foreign exchange losses from re-measurement		$ (1,388)	$ (314)
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	14.00%	18.00%	19.00%
Customer Concentration Risk [Member] \| Customer B [Member] \| Sales Revenue, Net [Member]
Schedule Of Significant Accounting Policies [Line Items]
Concentration risk, percentage	11.00%	13.00%	13.00%
Customer Concentration Risk [Member] \| Semiconductor Products [Member] \| Sales Revenue, Net [Member]
Schedule Of Significant Accounting Policies [Line Items]
Concentration risk, percentage	58.00%	69.00%	70.00%
Newport [Member]
Schedule Of Significant Accounting Policies [Line Items]
Advertising costs incurred	$ 992
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	12 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