RHOFADE Disposition - Amount Paid for Assets Acquired (Details) $ in Millions	1 Months Ended
Oct. 31, 2019 USD ($)
Business Acquisition [Line Items]
Percentage of payments received in connection with license or sublicense of assets transferred	25.00%
EPI Health, LLC
Business Acquisition [Line Items]
Closing consideration	$ 35.2
Potential milestones payable	$ 20.0
Period of royalty payment from first commercial sale	10 years
APA \| EPI Health, LLC
Business Acquisition [Line Items]
Percentage rights given for usage of cream	1.00%

The cash outflows associated with acquisition of product rights.

No definition available.

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

- Definition

The amount agreed to be paid by the buyer as a percentage of any upfront, license, milestone, maintenance or fixed payment received by the buyer in connection with any license or sublicense of the assets transferred in the disposition.

+ References

No definition available.

+ Details

Name:	acrs_PercentageOfPaymentsReceivedInConnectionWithLicenseOrSublicenseOfAssetsTransferred
Namespace Prefix:	acrs_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage rights given for usage of cream under asset purchase agreement.

+ References

No definition available.

+ Details

Name:	acrs_PercentageOfRightsGivenForUsageOfCream
Namespace Prefix:	acrs_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Period of royalty payment from the date of the first commercial sale of the product.

+ References

No definition available.

+ Details

Name:	acrs_PeriodOfRoyaltyPaymentFromFirstCommercialSale
Namespace Prefix:	acrs_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Future payments that could be paid upon achievement of certain milestones per agreement.

+ References

No definition available.

+ Details

Name:	acrs_PotentialMilestonesPayable
Namespace Prefix:	acrs_
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

No definition available.

+ Details

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

- Details

Name:	srt_CounterpartyNameAxis=acrs_EpiHealthLlcMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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