The term of agreement.

No definition available.

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- Definition

In a business combination, the maximum contingent consideration to be paid based upon achievement of certain milestones as set forth in the Agreement and Plan of Merger.

+ References

No definition available.

+ Details

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- Definition

The value of contingent consideration to be payable upon achievement of certain milestones.

+ References

No definition available.

+ Details

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- Definition

The amount of development costs reimbursed during the period.

+ References

No definition available.

+ Details

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

- Definition

The amount of cash outflow associated for license payments.

+ References

No definition available.

+ Details

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

- Definition

The amount of cash outflow for payment of upfront consideration.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The cash inflow associated with the amount received for regulatory and commercial milestones.

+ References

No definition available.

+ Details

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

- Definition

Amount of liability recognized arising from contingent consideration in a business combination, expected to be settled beyond one year or the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 805
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479581/805-30-50-2

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 805
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479581/805-30-50-1

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 808
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479402/808-10-50-1

+ Details

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Data Type:	xbrli:stringItemType
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Period Type:	duration

- Details

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- Details

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- Details

Name:	srt_CounterpartyNameAxis=acrs_SunPharmaceuticalIndustriesIncMember
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Data Type:	na
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- Details

Name:	us-gaap_TypeOfArrangementAxis=acrs_LicenseAndCollaborationAgreementMember
Namespace Prefix:
Data Type:	na
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- Details

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- Details

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- Details

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Agreements Related to Intellectual Property (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended		6 Months Ended		12 Months Ended
	Nov. 30, 2024	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2017	Dec. 31, 2025
Agreements Related to Intellectual Property
Contingent consideration		$ 11,300		$ 11,300			$ 11,000
Achievement Of Specified Regulatory Milestones
Agreements Related to Intellectual Property
Achievement of specified regulatory milestones	$ 125,000
Achievement Of Specified Sales Milestones
Agreements Related to Intellectual Property
Achievement of specified regulatory milestones	795,000
Sun Pharmaceutical Industries, Inc
Agreements Related to Intellectual Property
Regulatory and commercial milestones		100		300
License and Collaboration Agreement
Agreements Related to Intellectual Property
Upfront cash amount	30,000
Development costs of reimbursement	4,500
Cash payments	$ 6,200
Patent License Agreement \| Eli Lilly and Company
Agreements Related to Intellectual Property
Regulatory and commercial milestones		$ 1,100	$ 1,300	$ 2,400	$ 2,300
Agreement and Plan of Merger - Confluence
Agreements Related to Intellectual Property
Additional contingent consideration based on milestones, maximum, per Agreement						$ 75,000
Term of agreement						10 years