Schedule I And Quarterly Info Part II (Selected Quarterly Financial Results) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Total revenues									$ 49,666	$ 49,386	$ 47,542
Compensation and benefits									25,972	25,385	22,527
Business development, occupancy, equipment									3,402	2,995	2,723
Subscriptions, clearing, and execution									9,682	8,627	7,296
Professional fee and other operating									6,251	8,459	7,345
Depreciation and amortization									318	261	249
Total operating expenses									45,625	45,727	40,140
Operating income (loss)									4,041	3,659	7,402
Interest expense, net									7,584	8,487	6,178
Income (loss) from equity method affiliates									(553)
Income (loss) before income tax expense (benefit)									(4,096)	(4,828)	1,224
Income tax expense (benefit)									(523)	(841)	(1,211)
Net income (loss)									(3,573)	(3,987)	2,435
Less: comprehensive income (loss) attributable to the non-controlling interest									(1,518)	(1,562)	461
Net income (loss) attributable to Cohen & Company Inc.									$ (2,054)	$ (2,463)	$ 2,064
Basic income (loss) per common share									$ (1.81)	$ (2.14)	$ 1.71
Weighted average shares outstanding-basic									1,136,574	1,152,073	1,206,906
Diluted income (loss) per common share									$ (1.81)	$ (2.14)	$ 1.60
Weighted average shares outstanding-diluted									1,681,173	1,684,482	2,592,254
Cohen & Company [Member]
Total revenues	$ 16,090	$ 11,267	$ 11,169	$ 11,140	$ 15,621	$ 12,237	$ 12,190	$ 9,338	$ 1,340	$ 921	$ 4,939
Compensation and benefits	6,159	7,017	6,432	6,364	6,425	7,177	6,589	5,194
Business development, occupancy, equipment	926	770	895	811	759	725	644	867
Subscriptions, clearing, and execution	2,950	2,403	2,056	2,273	2,209	2,433	2,151	1,834
Professional fee and other operating	1,942	1,440	1,190	1,679	3,855	1,483	1,379	1,742
Depreciation and amortization	79	80	78	81	85	63	52	61
Total operating expenses	12,056	11,710	10,651	11,208	13,333	11,881	10,815	9,698
Operating income (loss)	4,034	(443)	518	(68)	2,288	356	1,375	(360)	1,340	921	4,939
Interest expense, net	(2,255)	(1,536)	(1,939)	(1,854)	(2,282)	(2,185)	(2,201)	(1,819)	(4,074)	(4,251)	(4,104)
Income (loss) from equity method affiliates	(188)	(109)	(248)	(8)
Income (loss) before income tax expense (benefit)	1,591	(2,088)	(1,669)	(1,930)	6	(1,829)	(826)	(2,179)	(2,734)	(3,330)	835
Income tax expense (benefit)	394	(170)	(641)	(106)	418	(595)	(636)	(28)	(680)	(867)	(1,229)
Net income (loss)	1,197	(1,918)	(1,028)	(1,824)	(412)	(1,234)	(190)	(2,151)	(2,054)	(2,463)	2,064
Less: comprehensive income (loss) attributable to the non-controlling interest	423	(702)	(618)	(622)	6	(583)	(270)	(677)
Net income (loss) attributable to Cohen & Company Inc.	$ 774	$ (1,216)	$ (410)	$ (1,202)	$ (418)	$ (651)	$ 80	$ (1,474)	$ (2,054)	$ (2,463)	$ 2,064
Basic income (loss) per common share	$ 0.69	$ (1.06)	$ (0.36)	$ (1.06)	$ (0.37)	$ (0.57)	$ 0.07	$ (1.26)
Weighted average shares outstanding-basic	1,125,311	1,143,909	1,143,909	1,133,166	1,117,576	1,145,323	1,172,919	1,172,476
Diluted income (loss) per common share	$ 0.56	$ (1.06)	$ (0.36)	$ (1.06)	$ (0.37)	$ (0.57)	$ 0.07	$ (1.26)
Weighted average shares outstanding-diluted	2,757,194	1,676,318	1,676,318	1,665,575	1,649,985	1,677,732	1,719,671	1,704,885