Percentage fee of original principal amount of debt at which debt can be redeemed by the issuer.

No definition available.

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Namespace Prefix:	acrs_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The debt instrument number of consecutive monthly payments.

+ References

No definition available.

+ Details

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Namespace Prefix:	acrs_
Data Type:	xbrli:durationItemType
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Period Type:	duration

- Definition

Percentage fee of original principal amount of debt at which debt can be redeemed by the issuer.

+ References

No definition available.

+ Details

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Namespace Prefix:	acrs_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ 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 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
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

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ 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 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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

- Definition

Amount of cash inflow (outflow) from long-term debt wholly or partially secured by collateral. Excludes tax exempt secured debt.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 3
-Subparagraph (SX 210.12-04(a))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24072-122690

+ Details

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

- Definition

The cash outflow to repay long-term debt that is wholly or partially secured by collateral. Excludes repayments of tax exempt secured debt.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3291-108585

+ Details

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

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Data Type:	na
Balance Type:
Period Type:

- Details

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Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Data Type:	na
Balance Type:
Period Type:

- Details

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Debt (Details) - USD ($) $ in Thousands			1 Months Ended
Debt (Details) - USD ($) $ in Thousands	Oct. 10, 2019	Oct. 15, 2018	Oct. 31, 2018
Debt Instrument [Line Items]
Loan, maximum borrowing capacity		$ 65,000
Loan amount borrowed			$ 30,000
Number of consecutive monthly payments		24 months
Final payment fee percentage		5.75%
Minimum
Debt Instrument [Line Items]
Annual interest rate		8.35%
Prepayment prior to the first anniversary of the Funding Date
Debt Instrument [Line Items]
Prepayment fee percentage		3.00%
Prepayment between the first and second anniversaries of the Funding Date
Debt Instrument [Line Items]
Prepayment fee percentage		2.00%
Prepayment after the second anniversary of the Funding Date but before October 1, 2023
Debt Instrument [Line Items]
Prepayment fee percentage		1.00%
London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Basis spread over LIBOR		6.25%
Subsequent event
Debt Instrument [Line Items]
Repayment of loan	$ 30,000