SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Schedule of equity securities (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Debt and Equity Securities, FV-NI [Line Items]
Cost	$ 99,859	$ 36,851
Gross Unrealized Gain	264,879	74,099
Gross Unrealized Loss	(2,960)	(1,847)
Fair Value	361,778	109,103
Trading securities - Debt
Debt and Equity Securities, FV-NI [Line Items]
Cost	56,037	32,765
Gross Unrealized Gain	262,811	72,689
Gross Unrealized Loss	(1,488)	(583)
Fair Value	317,360	104,871
Trading securities - Equity
Debt and Equity Securities, FV-NI [Line Items]
Cost	43,822	4,086
Gross Unrealized Gain	2,068	1,410
Gross Unrealized Loss	(1,472)	(1,264)
Fair Value	$ 44,418	$ 4,232