Annual report pursuant to Section 13 and 15(d)

Fair Value Measurements and Marketable Securities - Additional Information (Details)

v2.4.1.9
Fair Value Measurements and Marketable Securities - Additional Information (Details) (USD $)
12 Months Ended
Dec. 31, 2013
Dec. 31, 2014
Feb. 28, 2014
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]      
Financial assets measured on a recurring basis $ 0us-gaap_AssetsFairValueDisclosureRecurring $ 0us-gaap_AssetsFairValueDisclosureRecurring  
Fair value assets, level 1 to level 2 transfers 0us-gaap_FairValueAssetsLevel1ToLevel2TransfersAmount 0us-gaap_FairValueAssetsLevel1ToLevel2TransfersAmount  
Fair value liabilities, level 1 to level 2 transfers 0us-gaap_FairValueLiabilitiesLevel1ToLevel2TransfersAmount 0us-gaap_FairValueLiabilitiesLevel1ToLevel2TransfersAmount  
Fair value assets, level 2 to level 1 transfers 0us-gaap_FairValueAssetsLevel2ToLevel1TransfersAmount 0us-gaap_FairValueAssetsLevel2ToLevel1TransfersAmount  
Fair value liabilities, level 2 to level 1 transfers 0us-gaap_FairValueLiabilitiesLevel2ToLevel1TransfersAmount 0us-gaap_FairValueLiabilitiesLevel2ToLevel1TransfersAmount  
Marketable securities 0us-gaap_MarketableSecurities 0us-gaap_MarketableSecurities  
Proceeds from maturities and sales marketable securities 2,700,000us-gaap_ProceedsFromSaleAndMaturityOfMarketableSecurities    
Realized gains from marketable securities $ 2,000us-gaap_MarketableSecuritiesRealizedGainLoss    
Preferred Stock      
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]      
Outstanding warrants exercisable     2,344,731us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_PreferredStockMember
Outstanding warrants exercisable to preferred shares   0us-gaap_ClassOfWarrantOrRightOutstanding
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_PreferredStockMember
 
Common Stock      
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]      
Outstanding warrants exercisable     159,834us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_CommonStockMember