v3.25.4

Note 5 - Investment Banking and New Issue and Net Trading - Investment Banking and New Issue (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Cash revenue	$ 141,169	$ 39,084	$ 10,016
Noncash revenue	232,398	24,338	18,248
Revenue before gain (loss) on financial instruments	373,567	63,422	28,264
New Issue and Advisory [Member]
Revenue	187,608	40,778	23,952
Origination [Member]
Cash revenue	3,916	1,856	2,091
Noncash revenue	0	0	0
Revenue before gain (loss) on financial instruments	3,916	1,856	2,091
Cohen & Company Capital Markets (CCM) [Member] | Noncash Consideration [Member]
Gains / (losses) on CCM financial instruments received as non-cash consideration	(185,959)	(22,644)	(4,312)
Cohen & Company Capital Markets (CCM) [Member] | Underwriting [Member]
Cash revenue	46,995	4,733	0
Noncash revenue	14,633	1,423	0
Revenue before gain (loss) on financial instruments	61,628	6,156	0
Cohen & Company Capital Markets (CCM) [Member] | New Issue and Advisory [Member]
Cash revenue	90,258	32,495	7,925
Noncash revenue	217,765	22,915	18,248
Revenue before gain (loss) on financial instruments	$ 308,023	$ 55,410	$ 26,173

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