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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	19,000
Interest and penalties	133,000
State
Income Tax And Carryforwards [Line Items]
Operating loss carryforwards	3,787,000
Tax credit carryforwards	1,245,000
Foreign
Income Tax And Carryforwards [Line Items]
Operating loss carryforwards	4,281,000
Tax credit carryforwards	328,000
Federal
Income Tax And Carryforwards [Line Items]
Operating loss carryforwards	$ 963,000