Merger Agreement and Asset Sale (Details) $ in Thousands	Dec. 17, 2024 USD ($)
Merger Agreement and Asset Sale [Line Items]
Termination Fee	$ 2,250
Reimbursed expenses	750
Vifor Fresenius Medical Care Renal Pharma Ltd Agreement [Member]
Merger Agreement and Asset Sale [Line Items]
Asset Disposition, purchase price	900
Additional compensation for Asset Disposition	$ 3,000
Cara Therapeutics, Inc \| Pre-Merger equity holders of company
Merger Agreement and Asset Sale [Line Items]
Subsidiary, Ownership percentage	15.25%
Cara Therapeutics, Inc \| Pre-Merger Equity Holders of Tvardi
Merger Agreement and Asset Sale [Line Items]
Subsidiary, Ownership percentage	72.21%
Cara Therapeutics, Inc \| Holders of Tvardi Convertible Notes
Merger Agreement and Asset Sale [Line Items]
Subsidiary, Ownership percentage	12.54%

The amount agreed to pay to the third party for estimated incremental future expenses.

No definition available.

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

- Definition

The amount of purchase price for asset disposition.

+ References

No definition available.

+ Details

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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

No definition available.

+ Details

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Namespace Prefix:	cara_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of maximum reimbursement of certain expenses if merger does not close under termination agreement.

+ References

No definition available.

+ Details

Name:	cara_TerminationAgreementIfMergerDoesNotCloseMaximumAmountToBeReimbursed
Namespace Prefix:	cara_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of termination fee to be incurred if merger does not close under termination agreement.

+ References

No definition available.

+ Details

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

- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
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- Details

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Namespace Prefix:
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- Details

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Namespace Prefix:
Data Type:	na
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- Details

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Namespace Prefix:
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Balance Type:
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- Details

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Namespace Prefix:
Data Type:	na
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- Details

Name:	srt_CounterpartyNameAxis=cara_HoldersOfTvardiConvertibleNotesMember
Namespace Prefix:
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