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Equity Financings and Warrants (Details Textual) (USD $) | 12 Months Ended | 0 Months Ended | 1 Months Ended
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Dec. 31, 2014 | Dec. 31, 2013 | Jun. 04, 2013 | Jan. 22, 2013 | Feb. 07, 2014 | Feb. 03, 2014 | Feb. 04, 2013 | Jan. 31, 2013 | Feb. 28, 2014
Equity financings and warrants (Textual) [Abstract] |  |  |  |  |  |  |  |  |
Common stock, shares issued | 21,150,486 us-gaap_CommonStockSharesIssued | 15,685,562 us-gaap_CommonStockSharesIssued |  |  |  |  |  |  |
Proceeds from the issuance of common stock | $ 9,038,000 us-gaap_ProceedsFromIssuanceOfCommonStock | $ 1,741,000 us-gaap_ProceedsFromIssuanceOfCommonStock |  |  |  |  |  |  |
Proceeds from the issuance of preferred stock |  | 20,000,000 us-gaap_ProceedsFromIssuanceOfPreferredStockAndPreferenceStock |  |  |  |  |  |  |
Number of warrants outstanding | 9,371,002 us-gaap_ClassOfWarrantOrRightOutstanding |  |  |  |  |  |  |  |
Class of warrant or rights expiration date earliest | 2016-04 |  |  |  |  |  |  |  |
Class of warrant or rights expiration date latest | 2020-01 |  |  |  |  |  |  |  |
Minimum |  |  |  |  |  |  |  |  |
Equity financings and warrants (Textual) [Abstract] |  |  |  |  |  |  |  |  |
Warrant price per share | $ 1.60 us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1 / us-gaap_RangeAxis = us-gaap_MinimumMember |  |  |  |  |  |  |  |
Maximum |  |  |  |  |  |  |  |  |
Equity financings and warrants (Textual) [Abstract] |  |  |  |  |  |  |  |  |
Warrant price per share | $ 116.89 us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1 / us-gaap_RangeAxis = us-gaap_MaximumMember |  |  |  |  |  |  |  |
Weighted Average |  |  |  |  |  |  |  |  |
Equity financings and warrants (Textual) [Abstract] |  |  |  |  |  |  |  |  |
Warrant price per share | $ 2.31 us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1 / us-gaap_RangeAxis = us-gaap_WeightedAverageMember |  |  |  |  |  |  |  |
Public Offering | Preferred Stock |  |  |  |  |  |  |  |  |
Equity financings and warrants (Textual) [Abstract] |  |  |  |  |  |  |  |  |
Number of shares of preferred stock converted in to common stock |  | 125,000 abio_PreferredStockConvertedInToCommonStock / us-gaap_SecuritiesFinancingTransactionAxis = abio_PublicOfferingMember / us-gaap_StatementEquityComponentsAxis = us-gaap_PreferredStockMember |  |  |  |  |  |  |
Public Offering | Common stock |  |  |  |  |  |  |  |  |
Equity financings and warrants (Textual) [Abstract] |  |  |  |  |  |  |  |  |
Number of shares of common stock issued in conversion of preferred stock |  | 12,500,000 us-gaap_ConversionOfStockSharesConverted1 / us-gaap_SecuritiesFinancingTransactionAxis = abio_PublicOfferingMember / us-gaap_StatementEquityComponentsAxis = us-gaap_CommonStockMember |  |  |  |  |  |  |
Series A Convertible Preferred Stock | Preferred Stock |  |  |  |  |  |  |  |  |
Equity financings and warrants (Textual) [Abstract] |  |  |  |  |  |  |  |  |
Issuance of Series A convertible preferred stock, net of offering costs, shares |  | 125,000 abio_PreferredStockIssuedDuringPeriodSharesNewIssues / us-gaap_StatementClassOfStockAxis = us-gaap_ConvertiblePreferredStockMember / us-gaap_StatementEquityComponentsAxis = us-gaap_PreferredStockMember |  |  |  |  |  |  |
Series A Convertible Preferred Stock | Public Offering |  |  |  |  |  |  |  |  |
Equity financings and warrants (Textual) [Abstract] |  |  |  |  |  |  |  |  |
Warrants available to purchase additional commons shares |  |  | 6,250,000 us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights / us-gaap_SecuritiesFinancingTransactionAxis = abio_PublicOfferingMember / us-gaap_StatementClassOfStockAxis = us-gaap_ConvertiblePreferredStockMember |  |  |  |  |  |
Warrant coverage ratio |  |  | 50 us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight / us-gaap_SecuritiesFinancingTransactionAxis = abio_PublicOfferingMember / us-gaap_StatementClassOfStockAxis = us-gaap_ConvertiblePreferredStockMember |  |  |  |  |  |
Purchase price for common stock unit |  |  | $ 160 us-gaap_SharesIssuedPricePerShare / us-gaap_SecuritiesFinancingTransactionAxis = abio_PublicOfferingMember / us-gaap_StatementClassOfStockAxis = us-gaap_ConvertiblePreferredStockMember |  |  |  |  |  |
Warrants were exercisable upon issuance, expiry year |  |  | 5 years |  |  |  |  |  |
Warrant price per share |  |  | $ 1.60 us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1 / us-gaap_SecuritiesFinancingTransactionAxis = abio_PublicOfferingMember / us-gaap_StatementClassOfStockAxis = us-gaap_ConvertiblePreferredStockMember |  |  |  |  |  |
Proceeds from the issuance of common stock |  |  | 17,900,000 abio_NetProceedsFromIssuanceOfCommonStock / us-gaap_SecuritiesFinancingTransactionAxis = abio_PublicOfferingMember / us-gaap_StatementClassOfStockAxis = us-gaap_ConvertiblePreferredStockMember |  |  |  |  |  |
Issuance of Series A convertible preferred stock, net of offering costs, shares |  |  | 125,000 abio_PreferredStockIssuedDuringPeriodSharesNewIssues / us-gaap_SecuritiesFinancingTransactionAxis = abio_PublicOfferingMember / us-gaap_StatementClassOfStockAxis = us-gaap_ConvertiblePreferredStockMember |  |  |  |  |  |
Proceeds from the issuance of preferred stock |  |  | 20,000,000 us-gaap_ProceedsFromIssuanceOfPreferredStockAndPreferenceStock / us-gaap_SecuritiesFinancingTransactionAxis = abio_PublicOfferingMember / us-gaap_StatementClassOfStockAxis = us-gaap_ConvertiblePreferredStockMember |  |  |  |  |  |
Common stock shares issued upon conversion of each share of convertible preferred stock |  |  | 100 us-gaap_ConvertiblePreferredStockSharesIssuedUponConversion / us-gaap_SecuritiesFinancingTransactionAxis = abio_PublicOfferingMember / us-gaap_StatementClassOfStockAxis = us-gaap_ConvertiblePreferredStockMember |  |  |  |  |  |
Preferred stock liquidation preference per share |  |  | $ 0.001 us-gaap_PreferredStockLiquidationPreference / us-gaap_SecuritiesFinancingTransactionAxis = abio_PublicOfferingMember / us-gaap_StatementClassOfStockAxis = us-gaap_ConvertiblePreferredStockMember |  |  |  |  |  |
Percentage of total number of shares of common stock then issued and outstanding limit on beneficial ownership |  |  | 9.99%abio_PercentageOfSharesOfCommonStockThenIssuedAndOutstandingLimitOnBeneficialOwnership / us-gaap_SecuritiesFinancingTransactionAxis = abio_PublicOfferingMember / us-gaap_StatementClassOfStockAxis = us-gaap_ConvertiblePreferredStockMember |  |  |  |  |  |
Intrinsic value of embedded beneficial conversion feature |  |  | 2,000,000 abio_IntrinsicValueOfEmbeddedBeneficialConversionFeature / us-gaap_SecuritiesFinancingTransactionAxis = abio_PublicOfferingMember / us-gaap_StatementClassOfStockAxis = us-gaap_ConvertiblePreferredStockMember |  |  |  |  |  |
Director and Chief Executive Officer | Public Offering |  |  |  |  |  |  |  |  |
Equity financings and warrants (Textual) [Abstract] |  |  |  |  |  |  |  |  |
Warrants available to purchase additional commons shares |  |  | 39,050 us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights / us-gaap_SecuritiesFinancingTransactionAxis = abio_PublicOfferingMember / us-gaap_TitleOfIndividualAxis = abio_DirectorAndChiefExecutiveOfficerMember |  |  |  |  |  |
Preferred Stock Purchased by Officer |  |  | 781 abio_PreferredStockPurchasedByOfficer / us-gaap_SecuritiesFinancingTransactionAxis = abio_PublicOfferingMember / us-gaap_TitleOfIndividualAxis = abio_DirectorAndChiefExecutiveOfficerMember |  |  |  |  |  |
PIPE Transaction |  |  |  |  |  |  |  |  |
Equity financings and warrants (Textual) [Abstract] |  |  |  |  |  |  |  |  |
Common stock, shares issued |  |  |  | 356,430 us-gaap_CommonStockSharesIssued / us-gaap_SubsidiarySaleOfStockAxis = us-gaap_PrivatePlacementMember |  |  |  |  |
Warrants available to purchase additional commons shares |  |  |  | 249,501 us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights / us-gaap_SubsidiarySaleOfStockAxis = us-gaap_PrivatePlacementMember |  |  |  |  |
Aggregate gross proceeds |  |  |  | 1,000,000 us-gaap_ProceedsFromIssuanceOfPrivatePlacement / us-gaap_SubsidiarySaleOfStockAxis = us-gaap_PrivatePlacementMember |  |  |  |  |
Net proceeds from issuance of private placement |  |  |  | 805,000 abio_NetProceedsFromIssuanceOfPrivatePlacement / us-gaap_SubsidiarySaleOfStockAxis = us-gaap_PrivatePlacementMember |  |  |  |  |
Public Equity Offering Close Date | Jan. 25, 2013 |  |  |  |  |  |  |  |
Subscription agreement date | Jan. 22, 2013 |  |  |  |  |  |  |  |
Warrant coverage ratio |  |  |  | 0.70 us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight / us-gaap_SubsidiarySaleOfStockAxis = us-gaap_PrivatePlacementMember |  |  |  |  |
Purchase price for common stock unit |  |  |  | $ 2.81 us-gaap_SharesIssuedPricePerShare / us-gaap_SubsidiarySaleOfStockAxis = us-gaap_PrivatePlacementMember |  |  |  |  |
Warrants were exercisable upon issuance, expiry year |  |  |  | 7 years |  |  |  |  |
Warrant price per share |  |  |  | $ 2.28 us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1 / us-gaap_SubsidiarySaleOfStockAxis = us-gaap_PrivatePlacementMember |  |  |  |  |
Closing bid price of the common stock |  |  |  | 100.00%abio_ClassOfWarrantOrRightExercisePriceOfSharePercentageOfClosingBidPriceOfCommonShares / us-gaap_SubsidiarySaleOfStockAxis = us-gaap_PrivatePlacementMember |  |  |  |  |
Closing bid price date | Jan. 22, 2013 |  |  |  |  |  |  |  |
Registered Direct Offering |  |  |  |  |  |  |  |  |
Equity financings and warrants (Textual) [Abstract] |  |  |  |  |  |  |  |  |
Common stock, shares issued |  |  |  |  |  | 5,116,228 us-gaap_CommonStockSharesIssued / us-gaap_SubsidiarySaleOfStockAxis = abio_RegisteredDirectOfferingMember |  | 164,636 us-gaap_CommonStockSharesIssued / us-gaap_SubsidiarySaleOfStockAxis = abio_RegisteredDirectOfferingMember |
Warrants available to purchase additional commons shares |  |  |  |  |  | 1,279,057 us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights / us-gaap_SubsidiarySaleOfStockAxis = abio_RegisteredDirectOfferingMember |  | 65,855 us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights / us-gaap_SubsidiarySaleOfStockAxis = abio_RegisteredDirectOfferingMember |
Public Equity Offering Close Date | Feb. 07, 2014 |  |  |  |  |  |  | Feb. 04, 2013 |
Warrant coverage ratio |  |  |  |  |  | 0.25 us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight / us-gaap_SubsidiarySaleOfStockAxis = abio_RegisteredDirectOfferingMember |  | 0.40 us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight / us-gaap_SubsidiarySaleOfStockAxis = abio_RegisteredDirectOfferingMember |
Purchase price for common stock unit |  |  |  |  |  | $ 1.70 us-gaap_SharesIssuedPricePerShare / us-gaap_SubsidiarySaleOfStockAxis = abio_RegisteredDirectOfferingMember |  | $ 4.43 us-gaap_SharesIssuedPricePerShare / us-gaap_SubsidiarySaleOfStockAxis = abio_RegisteredDirectOfferingMember |
Warrants were exercisable upon issuance, expiry year |  |  |  |  |  | 5 years |  | 5 years |
Warrant price per share |  |  |  |  |  | $ 2.125 us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1 / us-gaap_SubsidiarySaleOfStockAxis = abio_RegisteredDirectOfferingMember |  | $ 4.13 us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1 / us-gaap_SubsidiarySaleOfStockAxis = abio_RegisteredDirectOfferingMember |
Closing bid price of the common stock |  |  |  |  |  | 125.00%abio_ClassOfWarrantOrRightExercisePriceOfSharePercentageOfClosingBidPriceOfCommonShares / us-gaap_SubsidiarySaleOfStockAxis = abio_RegisteredDirectOfferingMember |  |  |
Closing bid price date | Feb. 03, 2014 | Jan. 31, 2013 |  |  |  |  |  |  |
Proceeds from the issuance of common stock |  |  |  |  |  | 8,700,000 us-gaap_ProceedsFromIssuanceOfCommonStock / us-gaap_SubsidiarySaleOfStockAxis = abio_RegisteredDirectOfferingMember |  | 730,000 us-gaap_ProceedsFromIssuanceOfCommonStock / us-gaap_SubsidiarySaleOfStockAxis = abio_RegisteredDirectOfferingMember | 7,900,000 us-gaap_ProceedsFromIssuanceOfCommonStock / us-gaap_SubsidiarySaleOfStockAxis = abio_RegisteredDirectOfferingMember
Proceeds from the issuance of common stock |  |  |  |  | $ 7,900,000 abio_NetProceedsFromIssuanceOfCommonStock / us-gaap_SubsidiarySaleOfStockAxis = abio_RegisteredDirectOfferingMember |  | $ 616,000 abio_NetProceedsFromIssuanceOfCommonStock / us-gaap_SubsidiarySaleOfStockAxis = abio_RegisteredDirectOfferingMember |  |
Subscription agreement date |  |  |  |  |  |  |  | Jan. 31, 2013 |

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