v2.4.1.9

Income Taxes - Additional Information (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Tax And Carryforwards [Line Items]
Gross unrecognized tax benefits	$ 254,000us-gaap_UnrecognizedTaxBenefits	$ 273,000us-gaap_UnrecognizedTaxBenefits	$ 263,000us-gaap_UnrecognizedTaxBenefits
Unrecognized tax benefit, impact on effective tax rate	19,000us-gaap_UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate
Interest and penalties	133,000us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued
State
Income Tax And Carryforwards [Line Items]
Operating loss carryforwards	3,787,000us-gaap_OperatingLossCarryforwards / us-gaap_IncomeTaxAuthorityAxis = us-gaap_StateAndLocalJurisdictionMember
Tax credit carryforwards	1,245,000us-gaap_TaxCreditCarryforwardAmount / us-gaap_IncomeTaxAuthorityAxis = us-gaap_StateAndLocalJurisdictionMember
Foreign
Income Tax And Carryforwards [Line Items]
Operating loss carryforwards	4,281,000us-gaap_OperatingLossCarryforwards / us-gaap_IncomeTaxAuthorityAxis = us-gaap_ForeignCountryMember
Tax credit carryforwards	328,000us-gaap_TaxCreditCarryforwardAmount / us-gaap_IncomeTaxAuthorityAxis = us-gaap_ForeignCountryMember
Federal
Income Tax And Carryforwards [Line Items]
Operating loss carryforwards	$ 963,000us-gaap_OperatingLossCarryforwards / us-gaap_IncomeTaxAuthorityNameAxis = us-gaap_InternalRevenueServiceIRSMember

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Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

+ References

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The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

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Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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