Equity (Schedule Of Effects Of Changes In Ownership Interest Subsidiary) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Equity [Abstract]
Net income (loss) attributable to Cohen & Company Inc.	$ (3,102)	$ (1,202)
Increase / (decrease) in Cohen & Company Inc. paid in capital for the acquisition / (surrender) of additional units in consolidated subsidiary, net	123	(133)
Changes from net income / (loss) attributable to Cohen & Company Inc. and transfers (to) from non-controlling interest	$ (3,225)	$ (1,069)

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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