v2.4.1.9
Income Taxes - Additional Information (Detail) (USD $)
 12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Income Taxes Disclosure [Line Items]      
Pretax net losses $ (719,000)us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest $ (3,542,000)us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest $ (5,059,000)us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest
Benefit for income taxes (1,500,000)us-gaap_IncomeTaxExpenseBenefit 0us-gaap_IncomeTaxExpenseBenefit 0us-gaap_IncomeTaxExpenseBenefit
Decrease in valuation allowance 1,900,000us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount 500,000us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount  
Unrecognized tax benefits would impact the income tax provision 1,600,000us-gaap_UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate 1,500,000us-gaap_UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate  
Accrued interest and penalties related to unrecognized tax benefits 0us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued 0us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued 0us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued
Federal [Member]      
Income Taxes Disclosure [Line Items]      
Deferred tax benefit 1,500,000us-gaap_DeferredIncomeTaxExpenseBenefit
/ us-gaap_IncomeTaxAuthorityAxis
= us-gaap_DomesticCountryMember		    
Net operating loss carryforwards 164,000,000us-gaap_OperatingLossCarryforwards
/ us-gaap_IncomeTaxAuthorityAxis
= us-gaap_DomesticCountryMember		    
Operating loss carryforwards, expiration year 2018    
Tax credit carryforwards 3,100,000us-gaap_TaxCreditCarryforwardAmount
/ us-gaap_IncomeTaxAuthorityAxis
= us-gaap_DomesticCountryMember		    
Tax credit carryforwards, expiration year 2021    
State [Member]      
Income Taxes Disclosure [Line Items]      
Deferred tax benefit 0us-gaap_DeferredIncomeTaxExpenseBenefit
/ us-gaap_IncomeTaxAuthorityAxis
= us-gaap_StateAndLocalJurisdictionMember		    
Net operating loss carryforwards 127,000,000us-gaap_OperatingLossCarryforwards
/ us-gaap_IncomeTaxAuthorityAxis
= us-gaap_StateAndLocalJurisdictionMember		    
Operating loss carryforwards, expiration year 2015    
State [Member] | California [Member]      
Income Taxes Disclosure [Line Items]      
Tax credit carryforwards $ 3,900,000us-gaap_TaxCreditCarryforwardAmount
/ us-gaap_IncomeTaxAuthorityAxis
= us-gaap_StateAndLocalJurisdictionMember
/ us-gaap_StatementGeographicalAxis
= stpr_CA