Equity (Schedule Of Effects Of Changes In Ownership Interest Subsidiary) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Equity [Abstract]
Net income (loss) attributable to Cohen & Company Inc.	$ (651)	$ (547)	$ (2,045)	$ 551
Increase / (decrease) in Cohen & Company Inc. paid in capital for the acquisition / (surrender) of additional units in consolidated subsidiary, net			(139)	153
Changes from net income / (loss) attributable to Cohen & Company Inc. and transfers (to) from non-controlling interest			$ (2,184)	$ 704

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

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