v3.25.4

Note 8 - Financial Instruments - Other Investments, at Fair Value (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
Other Investments, Fair Value Disclosure	$ 57,258	$ 35,262
CREO JV [Member]
Other Investments, Fair Value Disclosure	8,940	6,432
U.S. Insurance JV [Member]
Other Investments, Fair Value Disclosure	2,375	2,825
Equity Securities [Member]
Other Investments, Fair Value Disclosure	21,457	11,072
Placement Unit and Warrants [Member]
Other Investments, Fair Value Disclosure	19,997	1,587
Corporate Bond Securities [Member]
Other Investments, Fair Value Disclosure	535	531
Fair Value Receivables [Member]
Notes receivable	2,783	11,250
Interest In SPVs [Member]
Other Investments, Fair Value Disclosure	0	1,565
CK Capital Value Fund [Member]
Other Investments, Fair Value Disclosure	$ 1,171	$ 0

X

- Definition

Amount of investments, other than trading securities, measured at fair value.

+ References

No definition available.

+ Details

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Namespace Prefix:	cohn_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

X

- Definition

Fair value portion of an agreement for an unconditional promise by the maker to pay the holder a definite sum of money at a future date.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 28
-Subparagraph (c)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482907/825-10-50-28

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 11
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482907/825-10-50-11

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 11
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482907/825-10-50-11

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-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

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