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Held To Maturity Investments Contractual Maturity

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Income Tax Rate Effective Date

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Minimum Alternative Tax On Income At Foreign Country

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Number Of Customers Accounting For Ten Percent Or More Of Consolidated Revenue

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Percentage Of Income Tax Examination Minimum Likelihood of Tax Benefits Being Realized Upon Ultimate Settlement

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Percentage of Ownership Interest Acquired

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Percentage of Revenue Accounted for by Top Ten Customers

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Short Term Investments, Maturity Period

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Warranty Period For Products

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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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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, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, netted by jurisdiction and classified as noncurrent.

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Amount after allocation of valuation allowances of noncurrent deferred tax asset attributable to deductible temporary differences and carryforwards. Noncurrent assets are expected to be realized or consumed after one year (or the normal operating cycle, if longer).

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Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences, before jurisdictional netting.

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Amount of deferred tax liability attributable to taxable temporary differences expected to be realized or consumed within one year or operating cycle, if longer.

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The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to other deductions.

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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 of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to deductions. Including, but not limited to, extraterritorial income exclusion deduction, qualified production activity deduction, dividend deduction, deduction for dividend paid to employee stock ownership plan, Medicare prescription drug benefit subsidy deduction, and other deductions.

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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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Summary Of Significant Accounting Policies - Additional Information (Detail) shares in Thousands, TWD in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2015 USD ($) Customer shares	Dec. 31, 2015 TWD Customer shares	Dec. 31, 2014 USD ($) Customer shares	Dec. 31, 2013 USD ($) Customer shares	Dec. 31, 2012 TWD
Significant Accounting Policies [Line Items]
Consolidated interest acquire in subsidiary	100.00%	100.00%
Top ten customer sales in percentage	72.00%	72.00%	76.00%	76.00%
Number of customers accounted for 10% or more sales \| Customer	1	1	2	2
Depreciation and amortization	$ 7,936		$ 6,917	$ 6,429
Warranty period for manufacturing defects of products	1 year	1 year
Evaluation of tax benefits realized upon settlement	50.00%	50.00%
Income tax under IBT act effective date	Jan. 01, 2006	Jan. 01, 2006
Minimum alternative tax on income under IBT act	10.00%	10.00%
Standard deduction tax amount \| TWD					TWD 1,000
Standard deduction tax rate					10.00%
Deferred income tax liabilities, noncurrent	$ 0
Deferred income tax assets, net	$ 610		1,521
Scenario, Previously Reported
Significant Accounting Policies [Line Items]
Deferred income tax assets, noncurrent			1,909
Deferred income tax liabilities, current			388
Scenario, Adjustment
Significant Accounting Policies [Line Items]
Deferred income tax liabilities, noncurrent			$ 388
Customers accounted for 10% or more \| Net sales
Significant Accounting Policies [Line Items]
Major customers percentage of net sales	30.00%	30.00%	47.00%	46.00%
Amended in August 2012
Significant Accounting Policies [Line Items]
Standard deduction tax amount \| TWD		TWD 500
Standard deduction tax rate	12.00%	12.00%
Amendment Effective Date	Jan. 01, 2013	Jan. 01, 2013
Minimum
Significant Accounting Policies [Line Items]
Short term investment maturity period	3 months	3 months
Maximum
Significant Accounting Policies [Line Items]
Short term investment maturity period	1 year	1 year
Held-to-maturity investment maturity period	1 year	1 year
American Depositary Shares
Significant Accounting Policies [Line Items]
The effect of dilutive securities of employee stock options and restricted stock units \| shares	384	384	546	577
Ordinary Shares
Significant Accounting Policies [Line Items]
The effect of dilutive securities of employee stock options and restricted stock units \| shares	1,534	1,534	2,183	2,308
Software \| Minimum
Significant Accounting Policies [Line Items]
Property plant and equipment estimated useful life	1 year	1 year
Software \| Maximum
Significant Accounting Policies [Line Items]
Property plant and equipment estimated useful life	5 years	5 years
Development technology \| Minimum
Significant Accounting Policies [Line Items]
Intangible asset amortized over estimated useful lives	3 years 6 months	3 years 6 months
Development technology \| Maximum
Significant Accounting Policies [Line Items]
Intangible asset amortized over estimated useful lives	4 years 6 months	4 years 6 months
Buildings \| Minimum
Significant Accounting Policies [Line Items]
Property plant and equipment estimated useful life	25 years	25 years
Buildings \| Maximum
Significant Accounting Policies [Line Items]
Property plant and equipment estimated useful life	50 years	50 years
Machinery and Equipment \| Minimum
Significant Accounting Policies [Line Items]
Property plant and equipment estimated useful life	3 years	3 years
Machinery and Equipment \| Maximum
Significant Accounting Policies [Line Items]
Property plant and equipment estimated useful life	6 years	6 years
Furniture and Fixtures \| Minimum
Significant Accounting Policies [Line Items]
Property plant and equipment estimated useful life	3 years	3 years
Furniture and Fixtures \| Maximum
Significant Accounting Policies [Line Items]
Property plant and equipment estimated useful life	8 years	8 years
Leasehold And Building Improvement \| Minimum
Significant Accounting Policies [Line Items]
Property plant and equipment estimated useful life	2 years	2 years
Leasehold And Building Improvement \| Maximum
Significant Accounting Policies [Line Items]
Property plant and equipment estimated useful life	6 years	6 years
FCI
Significant Accounting Policies [Line Items]
Consolidated interest acquire in subsidiary	99.90%	99.90%