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FAIR VALUE MEASUREMENTS - Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis (Details) - USD ($) $ in Thousands | Jun. 30, 2024 | Dec. 31, 2023
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Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments, at fair value | $ 687,507 | $ 701,964
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 | $ 4,879 | $ 2,789
Assets, fair value disclosure | 786,369 | 704,753
Securities sold, not yet purchased | 5,235 | 4,809
Contingent consideration liability | 4,389 | 6,583
Derivative liabilities | 274,033 | 368,673
Total of liabilities measured at fair value | 283,657 | 380,065
Fair Value, Measurements, Recurring | Debt |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments, at fair value | 99,254 | 4,285
Fair Value, Measurements, Recurring | Equity |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments, at fair value | 54,442 | 54,717
Fair Value, Measurements, Recurring | Alternative investments |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments, at fair value | 57,679 | 61,680
Fair Value, Measurements, Recurring | Debt |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments, at fair value | 145,151 | 191,325
Fair Value, Measurements, Recurring | Equity |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments, at fair value | 282,782 | 343,139
Fair Value, Measurements, Recurring | Private equity |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments, at fair value | 48,199 | 46,818
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 | 24,488 |
Fair Value, Measurements, Recurring | U.S. Treasury Securities |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Cash and cash equivalents | 69,495 |
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 | 669,846 | 598,186
Securities sold, not yet purchased | 5,235 | 4,809
Contingent consideration liability | 0 | 0
Derivative liabilities | 0 | 0
Total of liabilities measured at fair value | 5,235 | 4,809
Fair Value, Measurements, Recurring | Level 1 | Debt |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments, at fair value | 98,350 | 4,285
Fair Value, Measurements, Recurring | Level 1 | Equity |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments, at fair value | 53,831 | 54,224
Fair Value, Measurements, Recurring | Level 1 | Alternative investments |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments, at fair value | 10,540 | 15,676
Fair Value, Measurements, Recurring | Level 1 | Debt |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments, at fair value | 130,409 | 180,907
Fair Value, Measurements, Recurring | Level 1 | Equity |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments, at fair value | 282,733 | 343,094
Fair Value, Measurements, Recurring | Level 1 | Private equity |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments, at fair value | 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 | 24,488 |
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 | 69,495 |
Fair Value, Measurements, Recurring | Level 2 |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Derivative assets | 4,879 | 2,789
Assets, fair value disclosure | 20,522 | 13,202
Securities sold, not yet purchased | 0 | 0
Contingent consideration liability | 0 | 0
Derivative liabilities | 274,033 | 368,673
Total of liabilities measured at fair value | 274,033 | 368,673
Fair Value, Measurements, Recurring | Level 2 | Debt |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments, at fair value | 904 | 0
Fair Value, Measurements, Recurring | Level 2 | Equity |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments, at fair value | 0 | 0
Fair Value, Measurements, Recurring | Level 2 | Alternative investments |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments, at fair value | 0 | 0
Fair Value, Measurements, Recurring | Level 2 | Debt |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments, at fair value | 14,739 | 10,413
Fair Value, Measurements, Recurring | Level 2 | Equity |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments, at fair value | 0 | 0
Fair Value, Measurements, Recurring | Level 2 | Private equity |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments, at fair value | 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 |
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 |
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 | 875 | 766
Securities sold, not yet purchased | 0 | 0
Contingent consideration liability | 4,389 | 6,583
Derivative liabilities | 0 | 0
Total of liabilities measured at fair value | 4,389 | 6,583
Fair Value, Measurements, Recurring | Level 3 | Debt |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments, at fair value | 0 | 0
Fair Value, Measurements, Recurring | Level 3 | Equity |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments, at fair value | 611 | 493
Fair Value, Measurements, Recurring | Level 3 | Alternative investments |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments, at fair value | 0 | 0
Fair Value, Measurements, Recurring | Level 3 | Debt |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments, at fair value | 0 | 0
Fair Value, Measurements, Recurring | Level 3 | Equity |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments, at fair value | 0 | 0
Fair Value, Measurements, Recurring | Level 3 | Private equity |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments, at fair value | 264 | 273
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 |
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 |
Fair Value, Measurements, Recurring | NAV |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Derivative assets | 0 | 0
Assets, fair value disclosure | 95,126 | 92,599
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, at fair value | 0 | 0
Fair Value, Measurements, Recurring | NAV | Equity |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments, at fair value | 0 | 0
Fair Value, Measurements, Recurring | NAV | Alternative investments |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments, at fair value | 47,139 | 46,004
Fair Value, Measurements, Recurring | NAV | Debt |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments, at fair value | 3 | 5
Fair Value, Measurements, Recurring | NAV | Equity |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments, at fair value | 49 | 45
Fair Value, Measurements, Recurring | NAV | Private equity |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Investments, at fair value | 47,935 | $ 46,545
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 |
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 |

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