XML 59 R48.htm IDEA: XBRL DOCUMENT v3.8.0.1

Subsequent Event (Details Textual) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Jan. 19, 2018	Dec. 31, 2017	Dec. 31, 2016
Subsequent Event [Line Items]
Common stock, shares issued		11,775,062	9,082,366
Proceeds from the issuance of common stock		$ 6,551
Sales Agreement
Subsequent Event [Line Items]
Common stock, shares issued		2,677,525
Proceeds from the issuance of common stock		$ 6,600
Net proceeds from issuance of common stock		$ 6,100
Sales Agreement | Subsequent Event
Subsequent Event [Line Items]
Common stock, shares issued	2,133,828
Proceeds from the issuance of common stock	$ 3,500
Net proceeds from issuance of common stock	$ 3,400

X

- Definition

The cash inflow associated with the amount received from entity's raising of capital via registered direct offering, net of related financing costs.

+ References

No definition available.

+ Details

Name:	abio_NetProceedsFromIssuanceOfCommonStock
Namespace Prefix:	abio_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_CommonStockSharesIssued
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

X

- Definition

The cash inflow from the additional capital contribution to the entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3255-108585

+ Details

Name:	us-gaap_ProceedsFromIssuanceOfCommonStock
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

Name:	us-gaap_SubsequentEventLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Details

Name:	us-gaap_TypeOfArrangementAxis=abio_CapitalOnDemandSalesAgreementMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: