EQUITY SECURITIES PORTFOLIO INVESTMENT - Unrealized and Realized Gains or Losses on Investment (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Debt and Equity Securities, FV-NI [Line Items]
Change in fair value of investment	$ (26,701)	$ 3,343
Trading Securites - LF Fund Public Securities
Debt and Equity Securities, FV-NI [Line Items]
Change in fair value of investment	(28,581)	577
Realized investment gains (losses)	28,581	0
Trading Securites Lf Fund Securities
Debt and Equity Securities, FV-NI [Line Items]
Net realized and unrealized gain (loss) on investments	$ 0	$ 577

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
-Topic 944
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
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Amount of realized and unrealized gain (loss) on investment.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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