| **DESCRIPTION OF BUSINESS, BASIS OF PRESENTATION AND ACCOUNTING POLICIES - General (Details) $ in Thousands** | Apr. 11, 2022 USD ($) institutional_client employee | Mar. 31, 2023 USD ($) | Dec. 31, 2022 USD ($) |
|---------------------------------------------------------------------------------------------------------------|-----------------------------------------------------|-----------------------|-----------------------|
| **Noncontrolling Interest [Line Items]**                                                                      |                                                |                  |                  |
| Goodwill                                                                                                      |                                                | $ 2,766,665           | $ 2,767,732           |
| Pierpoint Capital Holdings LLC                                                                                |                                                |                  |                  |
| **Noncontrolling Interest [Line Items]**                                                                      |                                                |                  |                  |
| Acquisition, percentage of stock acquired                                                                     | 100.00%                                             |                  |                  |
| Fair value of consideration transferred                                                                       | $ 447,722                                           |                  |                  |
| Number of employees acquired | employee                                                                       | 230                                                 |                  |                  |
| Number of active institutional clients acquired | institutional_client                                        | 1,300                                               |                  |                  |
| Fair value measurement subject to refinement, term                                                            | 1 year                                              |                  |                  |
| Goodwill                                                                                                      | $ 170,571                                           |                  |                  |
| Finite-lived intangible assets acquired                                                                       | 39,000                                              |                  |                  |
| Business combination, unsecured intercompany loan                                                             | $ 163,000                                           |                  |                  |
| Pierpoint Capital Holdings LLC | Customer Relationships                                                       |                                                |                  |                  |
| **Noncontrolling Interest [Line Items]**                                                                      |                                                |                  |                  |
| Finite-lived intangible asset, useful life (in years)                                                         | 9 years                                             |                  |                  |
| Pierpoint Capital Holdings LLC | Technology                                                                   |                                                |                  |                  |
| **Noncontrolling Interest [Line Items]**                                                                      |                                                |                  |                  |
| Finite-lived intangible asset, useful life (in years)                                                         | 3 years                                             |                  |                  |

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