EQUITY SECURITIES - Summarized Financial Information (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Results of Operations
Pre-tax loss	$ (81,863)	$ 9,676	$ (95,057)	$ 21,891
Net loss	(73,493)	7,147	(83,800)	17,270
tZero.com, Inc.
Results of Operations
Revenues	266	820	764	1,560
Pre-tax loss	(3,088)	(8,067)	(8,295)	(13,447)
Net loss	$ (3,111)	$ (8,816)	$ (8,435)	$ (13,196)