v3.25.4

Note 10 - Derivative Financial Instruments - Balance Sheet Information (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
Derivative financial instruments, fair value, net	$ 20,403	$ 1,903
TBA and Other Forward MBS [Member] | Long [Member]
Derivative financial instruments, fair value, net	4,651	4,836
TBA and Other Forward MBS [Member] | Short [Member]
Derivative financial instruments, fair value, net	(4,245)	(4,050)
Equity Derivatives [Member] | Short [Member]
Derivative financial instruments, fair value, net	19,997	1,587
Share Forward Liabilities [Member] | Short [Member]
Derivative financial instruments, fair value, net	$ 0	$ (470)

X

- Definition

Fair value of the assets less the liabilities of a derivative or group of derivatives.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482907/825-10-50-10

+ Details

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

X

- Details

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

X

- Details

Name:	us-gaap_PositionAxis=us-gaap_LongMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_PositionAxis=us-gaap_ShortMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_DerivativeInstrumentRiskAxis=cohn_EquityDerivativesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_DerivativeInstrumentRiskAxis=cohn_ShareForwardLiabilitiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: