SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Schedule of Equity Securities (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022
Debt and Equity Securities, FV-NI [Line Items]
Cost	$ 44,670		$ 63,383
Gross Unrealized Gain	15,641	$ 14,819
Gross Unrealized Loss	(7,458)	(16,594)
Fair Value	52,853		61,608
Equity securities - Life Sciences Portfolio
Debt and Equity Securities, FV-NI [Line Items]
Cost	28,498		28,498
Gross Unrealized Gain	14,354	14,815
Gross Unrealized Loss	(666)	(617)
Fair Value	42,186		42,696
Equity securities - other common stock
Debt and Equity Securities, FV-NI [Line Items]
Cost	16,172		34,885
Gross Unrealized Gain	1,287	4
Gross Unrealized Loss	(6,792)	$ (15,977)
Fair Value	$ 10,667		$ 18,912