Note 23 - Related Party Transactions - Routine Transactions Recognized in the Statements of Operations (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024	Dec. 31, 2024
Asset management	$ 395	$ 473	$ 791	$ 974
Principal transactions and other income	(44)	(455)	89	(214)
Income (loss) from equity method affiliates	(1,437)	(5,996)	981	23,049	$ 21,704
Interest expense (income)	288	234	574	720
CREO JV [Member]
Asset management	131	187	282	371
Principal transactions and other income	(105)	(276)	(33)	(117)
U.S. Insurance JV [Member]
Asset management	264	286	509	603
Principal transactions and other income	46	(179)	107	(102)
Columbus Circle SPAC [Member]
Principal transactions and other income	15	0	15	0
Income (loss) from equity method affiliates	(1,307)	0	(1,307)	0
Columbus Circle SPAC	(10)	(26)	16	(52)
Other SPAC Sponsor Entities [Member]
Principal transactions and other income	0	0	0	5
Income (loss) from equity method affiliates	(663)	(5,985)	1,439	23,176
Dutch Real Estate Entities [Member]
Income (loss) from equity method affiliates	533	(11)	849	(127)
Equity Method Affiliates [Member]
Income (loss) from equity method affiliates	(1,437)	(5,996)	981	23,049
Columbus Circle SPAC	(10)	(26)	16	(52)
JKD Investor [Member]
Interest expense (income)	$ 288	$ 234	$ 574	$ 720