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Summary Of Significant Accounting Policies - Additional Information (Detail) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2016 USD ($) Customer shares	Dec. 31, 2015 USD ($) Customer shares	Dec. 31, 2014 USD ($) Customer shares
Significant Accounting Policies [Line Items]
Consolidated interest acquire in subsidiary	100.00%
Top ten customer sales in percentage	75.00%	72.00%	76.00%
Number of customers accounted for 10% or more sales | Customer	1	1	2
Depreciation and amortization | $	$ 9,482	$ 7,936	$ 6,917
Warranty period for manufacturing defects of products	1 year
Evaluation of tax benefits realized upon settlement	50.00%
Customers accounted for 10% or more | Net sales
Significant Accounting Policies [Line Items]
Major customers percentage of net sales	28.00%	30.00%	47.00%
Minimum
Significant Accounting Policies [Line Items]
Short term investment maturity period	3 months
Maximum
Significant Accounting Policies [Line Items]
Short term investment maturity period	1 year
Held-to-maturity investment maturity period	1 year
American Depositary Shares
Significant Accounting Policies [Line Items]
The effect of dilutive securities of employee stock options and restricted stock units	283	384	546
Ordinary Shares
Significant Accounting Policies [Line Items]
The effect of dilutive securities of employee stock options and restricted stock units	1,131	1,534	2,183
Software | Minimum
Significant Accounting Policies [Line Items]
Property plant and equipment estimated useful life	1 year
Software | Maximum
Significant Accounting Policies [Line Items]
Property plant and equipment estimated useful life	5 years
Development technology | Minimum
Significant Accounting Policies [Line Items]
Intangible asset amortized over estimated useful lives	3 years 6 months
Development technology | Maximum
Significant Accounting Policies [Line Items]
Intangible asset amortized over estimated useful lives	4 years 6 months
Buildings | Minimum
Significant Accounting Policies [Line Items]
Property plant and equipment estimated useful life	25 years
Buildings | Maximum
Significant Accounting Policies [Line Items]
Property plant and equipment estimated useful life	50 years
Machinery and Equipment | Minimum
Significant Accounting Policies [Line Items]
Property plant and equipment estimated useful life	3 years
Machinery and Equipment | Maximum
Significant Accounting Policies [Line Items]
Property plant and equipment estimated useful life	6 years
Furniture and Fixtures | Minimum
Significant Accounting Policies [Line Items]
Property plant and equipment estimated useful life	3 years
Furniture and Fixtures | Maximum
Significant Accounting Policies [Line Items]
Property plant and equipment estimated useful life	8 years
Leasehold And Building Improvement | Minimum
Significant Accounting Policies [Line Items]
Property plant and equipment estimated useful life	2 years
Leasehold And Building Improvement | Maximum
Significant Accounting Policies [Line Items]
Property plant and equipment estimated useful life	6 years

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Held To Maturity Investments Contractual Maturity

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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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