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Summary Of Significant Accounting Policies - Additional Information (Detail) shares in Thousands, $ in Thousands | 12 Months Ended
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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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