SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Schedule of significant unobservable inputs of level 3 financial assets and liabilities (Details) $ in Thousands	Mar. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair value	$ 452,496	$ 532,419
Total assets measured at fair value	1,315,265	1,524,874
Mandatorily redeemable noncontrolling interests issued after November 5, 2003	5,601	5,835
Contingent consideration	29,322	27,986
Total liabilities measured at fair value	41,346	42,421
Significant unobservable inputs (Level 3)
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair value	452,496	532,419
Total assets measured at fair value	1,127,175	1,268,057
Mandatorily redeemable noncontrolling interests issued after November 5, 2003	5,601	5,835
Contingent consideration	29,322
Total liabilities measured at fair value	$ 34,923	$ 33,820
Significant unobservable inputs (Level 3) \| Market interest rate
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Contingent earnout, measurement input, percent	0.085	0.085
Significant unobservable inputs (Level 3) \| Weighted Average \| Market interest rate
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Contingent earnout, measurement input, percent	0.085	0.085
Significant unobservable inputs (Level 3) \| Market approach
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair value	$ 572,900	$ 662,158
Fair value	231,837	19,897
Mandatorily redeemable noncontrolling interests issued after November 5, 2003	$ 5,601	$ 5,835
Significant unobservable inputs (Level 3) \| Market approach \| Operating income multiple
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Mandatorily redeemable noncontrolling interesting, measurement input	6.0	6.0
Significant unobservable inputs (Level 3) \| Market approach \| Minimum \| Multiple of EBITDA
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Equity securities, measurement input	2.3	0.7
Significant unobservable inputs (Level 3) \| Market approach \| Minimum \| Multiple of Sales
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Equity securities, measurement input	0.7	0.8
Loans receivable at fair value, measurement input	0.6
Significant unobservable inputs (Level 3) \| Market approach \| Minimum \| Market price of related security
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Equity securities, measurement input	0.05	0.04
Loans receivable at fair value, measurement input	17.22	19.87
Significant unobservable inputs (Level 3) \| Market approach \| Maximum \| Multiple of EBITDA
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Equity securities, measurement input	9.0	13.5
Significant unobservable inputs (Level 3) \| Market approach \| Maximum \| Multiple of Sales
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Equity securities, measurement input	3.8	3.8
Loans receivable at fair value, measurement input	0.7
Significant unobservable inputs (Level 3) \| Market approach \| Maximum \| Market price of related security
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Equity securities, measurement input	11.20	92.51
Significant unobservable inputs (Level 3) \| Market approach \| Weighted Average \| Multiple of EBITDA
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Equity securities, measurement input	8.1	7.1
Significant unobservable inputs (Level 3) \| Market approach \| Weighted Average \| Multiple of Sales
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Equity securities, measurement input	0.9	1.0
Loans receivable at fair value, measurement input	0.7
Significant unobservable inputs (Level 3) \| Market approach \| Weighted Average \| Market price of related security
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Equity securities, measurement input	10.74	12.27
Loans receivable at fair value, measurement input	17.22	19.87
Significant unobservable inputs (Level 3) \| Market approach \| Weighted Average \| Operating income multiple
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Mandatorily redeemable noncontrolling interesting, measurement input	6.0	6.0
Significant unobservable inputs (Level 3) \| Discounted cash flow
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair value	$ 58,579	$ 58,331
Fair value	220,659	512,522
Contingent consideration	$ 29,322	$ 27,985
Significant unobservable inputs (Level 3) \| Discounted cash flow \| EBITDA volatility
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Contingent earnout, measurement input, percent	0.700	0.70
Significant unobservable inputs (Level 3) \| Discounted cash flow \| Asset volatility
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Contingent earnout, measurement input, percent	0.690	0.69
Significant unobservable inputs (Level 3) \| Discounted cash flow \| Revenue volatility
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Contingent earnout, measurement input, percent		0.051
Significant unobservable inputs (Level 3) \| Discounted cash flow \| Minimum \| Market interest rate
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Equity securities, measurement input	0.202	0.202
Loans receivable at fair value, measurement input	0.139	0.100
Significant unobservable inputs (Level 3) \| Discounted cash flow \| Minimum \| Revenue volatility
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Contingent earnout, measurement input, percent	0.050
Significant unobservable inputs (Level 3) \| Discounted cash flow \| Maximum \| Market interest rate
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Equity securities, measurement input	0.213	0.570
Loans receivable at fair value, measurement input	0.272	0.416
Significant unobservable inputs (Level 3) \| Discounted cash flow \| Maximum \| Revenue volatility
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Contingent earnout, measurement input, percent	0.063
Significant unobservable inputs (Level 3) \| Discounted cash flow \| Weighted Average \| Market interest rate
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Equity securities, measurement input	0.212	0.246
Loans receivable at fair value, measurement input	0.184	0.171
Significant unobservable inputs (Level 3) \| Discounted cash flow \| Weighted Average \| EBITDA volatility
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Contingent earnout, measurement input, percent	0.700	0.70
Significant unobservable inputs (Level 3) \| Discounted cash flow \| Weighted Average \| Asset volatility
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Contingent earnout, measurement input, percent	0.690	0.69
Significant unobservable inputs (Level 3) \| Discounted cash flow \| Weighted Average \| Revenue volatility
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Contingent earnout, measurement input, percent	0.056	0.051
Significant unobservable inputs (Level 3) \| Option pricing model
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair value	$ 43,200	$ 15,149
Significant unobservable inputs (Level 3) \| Option pricing model \| Minimum \| Annualized volatility
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Equity securities, measurement input	0.250	0.250
Significant unobservable inputs (Level 3) \| Option pricing model \| Maximum \| Annualized volatility
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Equity securities, measurement input	1.880	1.870
Significant unobservable inputs (Level 3) \| Option pricing model \| Weighted Average \| Annualized volatility
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Equity securities, measurement input	0.730	0.750

Loans Receivable, Measurement Input

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Redeemable Noncontrolling Interest, Equity, Measurement Input

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No definition available.

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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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- Definition

Amount of liability recognized arising from contingent consideration in a business combination.

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Value of input used to measure contingent consideration liability from business combination.

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- Definition

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

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Value of input used to measure investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Fair value of financial and nonfinancial obligations.

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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

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The aggregate fair value as of the reporting date of all noncontrolling interests which are redeemable by the (parent) entity (1) at a fixed or determinable price on a fixed or determinable date, (2) at the option of the holder of the noncontrolling interest, or (3) upon occurrence of an event that is not solely within the control of the (parent) entity. This item includes noncontrolling interest holder's ownership (or holders' ownership) regardless of the type of equity interest (common, preferred, other) including all potential organizational (legal) forms of the investee entity.

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