EQUITY SECURITIES PORTFOLIO INVESTMENT - Unrealized and Realized Gains or Losses on Investment (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Debt and Equity Securities, FV-NI [Line Items]
Change in fair value of investment			$ (266,202)	$ 115,509
Trading Securites - LF Fund Public Securities
Debt and Equity Securities, FV-NI [Line Items]
Change in fair value of investment	$ (39,008)	$ 243,930	(243,106)	214,247
Realized investment gains (losses)	36,397	37,112	101,102	52,167
Equity Securities - LF Fund Private Securities
Debt and Equity Securities, FV-NI [Line Items]
Change in fair value of investment	0	(180,023)	0	(102,067)
Trading Securites Lf Fund Securities
Debt and Equity Securities, FV-NI [Line Items]
Net realized and unrealized gain (loss) on investments	$ (2,611)	$ 101,019	$ (142,004)	$ 164,347

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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