Common stock, authorized offering amount under agreement to sell.

No definition available.

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- Definition

Equity financing and warrants.

+ References

No definition available.

+ Details

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- 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

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Namespace Prefix:	abio_
Data Type:	xbrli:monetaryItemType
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Period Type:	duration

- Definition

Selling commission per additional shares sold percentage.

+ References

No definition available.

+ Details

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Namespace Prefix:	abio_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Face amount or stated value per share of common stock.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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

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- 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

+ Details

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- Details

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- Details

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Equity Financings and Warrants (Details Textual) - USD ($)	3 Months Ended	12 Months Ended
	Mar. 31, 2020	Dec. 31, 2019	Jun. 28, 2019	Jan. 11, 2017
Equity Financing And Warrants [Line Items]
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares issued	1,594,070	1,594,070
JonesTrading
Equity Financing And Warrants [Line Items]
Percentage of selling commission per additional shares sold				3.00%
Sales Agreement
Equity Financing And Warrants [Line Items]
Common stock, shares issued	0	820,561
Net proceeds from issuance of common stock	$ 0	$ 6,900,000
Sales Agreement \| JonesTrading
Equity Financing And Warrants [Line Items]
Common stock, par value				$ 0.001
Aggregate offering price of common stock authorized			$ 17,500,000	$ 7,300,000