Stockholders' Equity - Other Offerings and ATM Facility (Details) - At The Market Offering - Silicon Valley Bank Securities LLC and Cantor Fitzgerald & Co. shares in Millions, $ in Millions	1 Months Ended
Apr. 30, 2023 USD ($) shares
Subsidiary, Sale of Stock [Line Items]
Common stock, sold \| shares	3.4
Aggregate gross proceeds	$ 27.5
Payments of stock offering costs	$ 0.8

The cash inflow from issuance of common stock, gross before deducting underwriting discounts, commissions and offering expenses.

No definition available.

+ Details

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Namespace Prefix:	acrs_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The cash outflow for cost incurred directly with the issuance of an equity security.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482740/230-10-45-15

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

Number of shares of stock issued as of the balance sheet date, including shares that had been issued and were previously outstanding but which are now held in the treasury.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-SubTopic 10
-Topic 505
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-2

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Details

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- Details

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