EQUITY SECURITIES PORTFOLIO INVESTMENT - Unrealized and Realized Gains or Losses on Investment (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Debt and Equity Securities, FV-NI [Line Items]
Change in fair value of investment			$ (229,850)	$ 49,007
Trading Securites - LF Fund Public Securities
Debt and Equity Securities, FV-NI [Line Items]
Change in fair value of investment	$ (32,458)	$ (35,057)	(204,098)	(29,683)
Realized investment gains (losses)	5,217	15,055	64,705	15,055
Equity Securities - LF Fund Private Securities
Debt and Equity Securities, FV-NI [Line Items]
Change in fair value of investment	0	46,154	0	77,956
Trading Securites Lf Fund Securities
Debt and Equity Securities, FV-NI [Line Items]
Net realized and unrealized gain (loss) on investments	$ (27,241)	$ 26,152	$ (139,393)	$ 63,328

Amount of unrealized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(3)(d))
-URI http://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263

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-Section 50
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Amount of realized and unrealized gain (loss) on investment.

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