Note 25 - Net Capital Requirements - Statutory Net Capital Requirements (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
Actual Net Capital or Liquid Capital	$ 79,119	$ 49,988
Amount Required	964	893
Excess	78,155	49,095
Cohen Securities [Member]
Actual Net Capital or Liquid Capital	77,093	48,414
Amount Required	250	250
Excess	76,843	48,164
CCFESA [Member]
Actual Net Capital or Liquid Capital	2,026	1,574
Amount Required	714	643
Excess	$ 1,312	$ 931

Amount of net capital in excess of minimum required net capital, calculated under Aggregate Indebtedness Standard.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Rule 15c3-1
-Number 240
-Section 15c3-1
-Publisher SEC

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Minimum amount of net capital required to be maintained by broker-dealer and its subsidiary, calculated under Aggregate Indebtedness Standard.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Rule 15c3-1
-Number 240
-Section 15c3-1
-Publisher SEC

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Data Type:	xbrli:monetaryItemType
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Amount of net capital of broker-dealer.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Rule 15c3-1
-Number 240
-Section 15c3-1
-Publisher SEC

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Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	dei_LegalEntityAxis=cohn_CCFESAMember
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