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FAIR VALUE MEASUREMENTS - Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis (Details) - USD ($) $ in Thousands | Sep. 30, 2025 | Dec. 31, 2024
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Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments | $ 605,080 | $ 598,048
Derivative Asset, Statement of Financial Position [Extensible Enumeration] | Other assets | Other assets
Derivative Liability, Statement of Financial Position [Extensible Enumeration] | Other liabilities | Other liabilities
Fair Value, Measurements, Recurring |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Derivative assets | $ 523 | $ 3,787
Assets, fair value disclosure | 635,456 | 632,483
Securities sold, not yet purchased | 4,076 | 4,529
Contingent consideration liability | 2,274 | 4,495
Derivative liabilities | 222,587 | 274,280
Total of liabilities measured at fair value | 228,937 | 283,304
Fair Value, Measurements, Recurring | Debt |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments | 1,704 |
Fair Value, Measurements, Recurring | Equity |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments | 58,530 | 58,623
Fair Value, Measurements, Recurring | Alternative investments |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments | 50,001 | 59,230
Fair Value, Measurements, Recurring | Debt |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments | 116,531 | 147,173
Fair Value, Measurements, Recurring | Equity |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments | 330,496 | 289,610
Fair Value, Measurements, Recurring | Private equity |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments | 47,818 | 43,412
Fair Value, Measurements, Recurring | U.S. Treasury Securities |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Deposits with banks and short-term investments | 29,753 | 24,666
Fair Value, Measurements, Recurring | U.S. Treasury Securities |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Cash and cash equivalents |  | 5,982
Restricted cash | 100 |
Fair Value, Measurements, Recurring | Level 1 |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Derivative assets | 0 | 0
Assets, fair value disclosure | 530,750 | 517,693
Securities sold, not yet purchased | 4,076 | 4,529
Contingent consideration liability | 0 | 0
Derivative liabilities | 0 | 0
Total of liabilities measured at fair value | 4,076 | 4,529
Fair Value, Measurements, Recurring | Level 1 | Debt |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments | 1,300 |
Fair Value, Measurements, Recurring | Level 1 | Equity |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments | 57,845 | 58,034
Fair Value, Measurements, Recurring | Level 1 | Alternative investments |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments | 6,825 | 10,763
Fair Value, Measurements, Recurring | Level 1 | Debt |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments | 104,795 | 129,004
Fair Value, Measurements, Recurring | Level 1 | Equity |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments | 330,132 | 289,244
Fair Value, Measurements, Recurring | Level 1 | Private equity |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments | 0 | 0
Fair Value, Measurements, Recurring | Level 1 | U.S. Treasury Securities |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Deposits with banks and short-term investments | 29,753 | 24,666
Fair Value, Measurements, Recurring | Level 1 | U.S. Treasury Securities |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Cash and cash equivalents |  | 5,982
Restricted cash | 100 |
Fair Value, Measurements, Recurring | Level 2 |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Derivative assets | 523 | 3,787
Assets, fair value disclosure | 12,963 | 22,269
Securities sold, not yet purchased | 0 | 0
Contingent consideration liability | 0 | 0
Derivative liabilities | 222,587 | 274,280
Total of liabilities measured at fair value | 222,587 | 274,280
Fair Value, Measurements, Recurring | Level 2 | Debt |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments | 404 |
Fair Value, Measurements, Recurring | Level 2 | Equity |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments | 0 | 0
Fair Value, Measurements, Recurring | Level 2 | Alternative investments |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments | 0 | 0
Fair Value, Measurements, Recurring | Level 2 | Debt |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments | 11,733 | 18,166
Fair Value, Measurements, Recurring | Level 2 | Equity |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments | 303 | 316
Fair Value, Measurements, Recurring | Level 2 | Private equity |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments | 0 | 0
Fair Value, Measurements, Recurring | Level 2 | U.S. Treasury Securities |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Deposits with banks and short-term investments | 0 | 0
Fair Value, Measurements, Recurring | Level 2 | U.S. Treasury Securities |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Cash and cash equivalents |  | 0
Restricted cash | 0 |
Fair Value, Measurements, Recurring | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Derivative assets | 0 | 0
Assets, fair value disclosure | 975 | 845
Securities sold, not yet purchased | 0 | 0
Contingent consideration liability | 2,274 | 4,495
Derivative liabilities | 0 | 0
Total of liabilities measured at fair value | 2,274 | 4,495
Fair Value, Measurements, Recurring | Level 3 | Debt |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments | 0 |
Fair Value, Measurements, Recurring | Level 3 | Equity |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments | 685 | 589
Fair Value, Measurements, Recurring | Level 3 | Alternative investments |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments | 0 | 0
Fair Value, Measurements, Recurring | Level 3 | Debt |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments | 0 | 0
Fair Value, Measurements, Recurring | Level 3 | Equity |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments | 0 | 0
Fair Value, Measurements, Recurring | Level 3 | Private equity |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments | 290 | 256
Fair Value, Measurements, Recurring | Level 3 | U.S. Treasury Securities |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Deposits with banks and short-term investments | 0 | 0
Fair Value, Measurements, Recurring | Level 3 | U.S. Treasury Securities |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Cash and cash equivalents |  | 0
Restricted cash | 0 |
Fair Value, Measurements, Recurring | NAV |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Derivative assets | 0 | 0
Assets, fair value disclosure | 90,768 | 91,676
Securities sold, not yet purchased | 0 | 0
Contingent consideration liability | 0 | 0
Derivative liabilities | 0 | 0
Total of liabilities measured at fair value | 0 | 0
Fair Value, Measurements, Recurring | NAV | Debt |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments | 0 |
Fair Value, Measurements, Recurring | NAV | Equity |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments | 0 | 0
Fair Value, Measurements, Recurring | NAV | Alternative investments |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments | 43,176 | 48,467
Fair Value, Measurements, Recurring | NAV | Debt |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments | 3 | 3
Fair Value, Measurements, Recurring | NAV | Equity |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments | 61 | 50
Fair Value, Measurements, Recurring | NAV | Private equity |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments | 47,528 | 43,156
Fair Value, Measurements, Recurring | NAV | U.S. Treasury Securities |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Deposits with banks and short-term investments | 0 | 0
Fair Value, Measurements, Recurring | NAV | U.S. Treasury Securities |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Cash and cash equivalents |  | $ 0
Restricted cash | $ 0 |

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- Definition Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. 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