| **DESCRIPTION OF BUSINESS, BASIS OF PRESENTATION AND ACCOUNTING POLICIES - General (Details) $ in Millions** | Apr. 11, 2022 USD ($) institutional_client employee | Dec. 31, 2023 USD ($) |
|--------------------------------------------------------------------------------------------------------------|-----------------------------------------------------|-----------------------|
| FDIC | Structured LLC                                                                                        |                                                |                  |
| **Noncontrolling Interest [Line Items]**                                                                     |                                                |                  |
| Equity ownership, excluding consolidated entity and equity method investee, percentage                       |                                                | 20.00%                |
| Joint venture, acquired amount                                                                               |                                                | $ 1,100               |
| Joint venture portfolio amount                                                                               |                                                | $ 9,000               |
| Pierpoint Capital Holdings LLC                                                                               |                                                |                  |
| **Noncontrolling Interest [Line Items]**                                                                     |                                                |                  |
| Acquisition, percentage of stock acquired                                                                    | 100.00%                                             |                  |
| Fair value of consideration transferred                                                                      | $ 448                                               |                  |
| Number of employees acquired | employee                                                                      | 230                                                 |                  |
| Number of active institutional clients acquired | institutional_client                                       | 1,300                                               |                  |

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| - Definition
Percentage of voting equity interests acquired at the acquisition date in the business combination.
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|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.
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| - Definition
Percentage of ownership of equity interest excluding interest in entity that is consolidated and equity method investee.
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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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