Quarterly report pursuant to Section 13 or 15(d)

Basis of Presentation - Additional Information (Detail)

v2.4.1.9
Basis of Presentation - Additional Information (Detail) (USD $)
3 Months Ended 12 Months Ended
Mar. 31, 2015
Mar. 31, 2014
Dec. 31, 2013
Dec. 31, 2014
Organization, Consolidation and Presentation of Financial Statements [Abstract]        
Revenues generated by company $ 363,774us-gaap_Revenues $ 214,660us-gaap_Revenues    
Net loss 1,292,777us-gaap_NetIncomeLoss 1,640,884us-gaap_NetIncomeLoss    
Cash used in operations 1,288,371us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperations 1,584,248us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperations    
Accumulated deficit 77,237,412us-gaap_RetainedEarningsAccumulatedDeficit     75,944,635us-gaap_RetainedEarningsAccumulatedDeficit
Gross proceeds from issuance of common stock     3,900,000ogen_ProceedsFromIssuanceOfCommonStockGross  
Net proceeds from issuance of common stock     $ 9,904,996ogen_ProceedsFromIssuanceOfCommonStockNetOfOfferingCost