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Fair Value Disclosures (Details) (USD $)
3 Months Ended
Mar. 31, 2015
Fair Value Disclosures (Textual) [Abstract]  
Transfers of assets between fair value hierarchy levels $ 0abio_FairValueAssetsBetweenHierarchyLevelsTransfersAmount
Fair Value Measurements, Recurring | Level 1 | Money Market Funds  
Fair Value Disclosures (Textual) [Abstract]  
Cash equivalents consisting of money market funds $ 12,100,000us-gaap_CashAndCashEquivalentsFairValueDisclosure
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_MoneyMarketFundsMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember