The amount of milestone payment receivable under the collaboration and license agreement.

No definition available.

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Namespace Prefix:	cara_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The percentage of net profits sharing.

+ References

No definition available.

+ Details

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Namespace Prefix:	cara_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The amount of potential milestone payment of common stock investment.

+ References

No definition available.

+ Details

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Namespace Prefix:	cara_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The amount of potential payment upon achievement of certain sales-based milestones.

+ References

No definition available.

+ Details

Name:	cara_PotentialSalesMilestonePayment
Namespace Prefix:	cara_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_TypeOfArrangementAxis=cara_ViforFreseniusMedicalCareRenalPharmaLtdAgreementNo2Member
Namespace Prefix:
Data Type:	na
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- Details

Name:	us-gaap_TypeOfArrangementAxis=cara_LicenseAgreementWithMaruishiPharmaceuticalCo.LtdMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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- Details

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- Details

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Namespace Prefix:
Data Type:	na
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Period Type:

- Details

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- Details

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Namespace Prefix:
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- Details

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- Details

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- Details

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Collaboration and Licensing Agreements - Additional Information (Detail) - USD ($) $ in Thousands	1 Months Ended
	Oct. 31, 2020	May 31, 2018	Sep. 30, 2023	May 17, 2018
Vifor Fresenius Medical Care Renal Pharma Ltd Agreement No 2 [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Percentage of net profit sharing		50.00%
License Agreement with Maruishi Pharmaceutical Co. Ltd [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Earned milestone payment			$ 1,449
CSL Vifor Maximum [Member] \| Vifor Fresenius Medical Care Renal Pharma Ltd Agreement No 1 [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Potential sales-based milestone payments	$ 240,000
CSL Vifor [Member] \| Vifor Fresenius Medical Care Renal Pharma Ltd Agreement No 1 [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Percentage of net profit sharing	40.00%
Affiliated Entity [Member] \| CSL Vifor [Member] \| Vifor Fresenius Medical Care Renal Pharma Ltd Agreement No 1 [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Percentage of net profit sharing	60.00%
Affiliated Entity [Member] \| Vifor Fresenius Medical Care Renal Pharma Ltd. [Member] \| Vifor Fresenius Medical Care Renal Pharma Ltd Agreement No 2 [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Percentage of net profit sharing		50.00%
Affiliated Entity [Member] \| Vifor Fresenius Medical Care Renal Pharma Ltd. [Member] \| Maximum [Member] \| Regulatory and Commercial Milestones [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Potential milestone payments				$ 440,000