Class of Warrant Or Right, Exercised During Period

No definition available.

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Period Type:	duration

- Definition

Issuance of Contingent Value Right for Exercise of Warrants

+ References

No definition available.

+ Details

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Namespace Prefix:	rnac_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Exercise price per share or per unit of warrants or rights outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-3

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

The cash inflow associated with the amount received from holders exercising their stock warrants.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 14
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-14

+ Details

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Balance Type:	debit
Period Type:	duration

- 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 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481990/310-10-45-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479134/946-220-S99-1

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Cash received on stock transaction after deduction of issuance costs.

+ References

No definition available.

+ Details

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

- Definition

The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

+ References

No definition available.

+ Details

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

- Definition

Number of shares issued during the period as a result of the conversion of convertible securities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-SubTopic 10
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-Publisher FASB
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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-Publisher FASB
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+ Details

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Period Type:	duration

- Details

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Namespace Prefix:
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Period Type:

- Details

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Data Type:	na
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Period Type:

- Details

Name:	us-gaap_SubsidiarySaleOfStockAxis=rnac_SecuritiesPurchaseAgreement2023Member
Namespace Prefix:
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Related-Party Transactions - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands			12 Months Ended
	Mar. 26, 2024	Nov. 13, 2023	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Related Party Transaction [Line Items]
Exercise price (in dollars per share)			$ 46.96	$ 45.98	$ 46.03
Proceeds from exercise of common warrants			$ 2,877	$ 0
Related Party
Related Party Transaction [Line Items]
Conversion of Series A and Series B preferred stock to common stock (in shares)	65,681
Issuance of CVRs upon exercise of warrants (in shares)	1,970,443
Related Party \| 2019 Warrants
Related Party Transaction [Line Items]
Warrants exercised (in shares)	65,681
Exercise price (in dollars per share)	$ 43.80
Proceeds from exercise of common warrants	$ 2,900
2023 Securities Purchase Agreement
Related Party Transaction [Line Items]
Sale of stock, number of shares issued in transaction (in shares)		149,330.115
Total aggregate purchase price		$ 60,250
2023 Securities Purchase Agreement \| Related Party
Related Party Transaction [Line Items]
Sale of stock, number of shares issued in transaction (in shares)		149,330.115
Total aggregate purchase price		$ 60,250