| **FAIR VALUE - Quantitative Information (Details) $ in Thousands** | Sep. 30, 2022 USD ($) | Dec. 31, 2021 USD ($) |
|--------------------------------------------------------------------|-----------------------|-----------------------|
| **Financial Assets:**                                              |                  |                  |
| MSRs                                                               | $ 110,411             | $ 79,107              |
| Level 3 | MSRs                                                     |                  |                  |
| **Financial Assets:**                                              |                  |                  |
| MSRs                                                               | $ 110,411             | $ 79,107              |
| Level 3 | MSRs | CPR | Minimum                                     |                  |                  |
| **Financial Assets:**                                              |                  |                  |
| Unobservable inputs (as a percent)                                 | 0.0381                | 0.0742                |
| Level 3 | MSRs | CPR | Maximum                                     |                  |                  |
| **Financial Assets:**                                              |                  |                  |
| Unobservable inputs (as a percent)                                 | 1.0000                | 0.8271                |
| Level 3 | MSRs | CPR | Weighted Average                            |                  |                  |
| **Financial Assets:**                                              |                  |                  |
| Unobservable inputs (as a percent)                                 | 0.0760                | 0.1286                |
| Level 3 | MSRs | Discount rate                                     |                  |                  |
| **Financial Assets:**                                              |                  |                  |
| Unobservable inputs (as a percent)                                 | 0.0935                | 0.0935                |

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| - Definition
Aggregate amount of servicing assets that are subsequently measured at fair value and servicing assets that are subsequently measured using the amortization method.
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| - Definition
Value of input used to measure servicing asset.
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