The period for which continuous service must be performed in order for awards to be modified.

No definition available.

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- Definition

Awards that vested during the period following consulting period are deemed to be type 3 modifications.

+ References

No definition available.

+ Details

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- Definition

The incremental cost of the modification of stock options.

+ References

No definition available.

+ Details

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Namespace Prefix:	cara_
Data Type:	xbrli:monetaryItemType
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Period Type:	duration

- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

+ Details

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(02)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

+ 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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Namespace Prefix:	us-gaap_
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- Definition

An excess of the fair value of the modified award over the fair value of the award immediately before the modification.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(2)(iii)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(2)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Details

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- Details

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- Details

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- Details

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Namespace Prefix:
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Stock-Based Compensation - Stock Award Modifications (Details) - USD ($) $ in Thousands	1 Months Ended		3 Months Ended	9 Months Ended
	Feb. 28, 2022	Nov. 30, 2021	Sep. 30, 2022	Sep. 30, 2022
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total incremental stock compensation expense relating to modifications of Stock Awards			$ 0
Modified Awards [Member] \| Former President and C E O [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period of awards granted		12 months
Share-based Compensation Arrangement Period During Which Continuous Service Must Be Performed For Awards To Be Modified		12 months
Awards that would have vested during the period following the consulting period are deemed to be type 3 modifications		12 months
Term of modified exercise period of awards		18 months
Modified Awards [Member] \| Former President and C E O [Member] \| General and Administrative [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total incremental stock compensation expense relating to modifications of Stock Awards				$ 2,563
Incremental stock compensation expense relating to modification of stock options				$ 1,679
Modified Awards [Member] \| Former President and C E O [Member] \| Performance Restricted Stock Units [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted stock units, vested	17,333