| **FAIR VALUE - Quantitative Information (Details) $ in Thousands** | Sep. 30, 2023 USD ($) | Dec. 31, 2022 USD ($) |
|--------------------------------------------------------------------|-----------------------|-----------------------|
| **Financial Assets:**                                              |                  |                  |
| MSRs                                                               | $ 104,523             | $ 107,383             |
| Level 3 | Mortgage servicing                                       |                  |                  |
| **Financial Assets:**                                              |                  |                  |
| MSRs                                                               | $ 104,523             | $ 107,383             |
| Level 3 | Mortgage servicing | Discount rate                       |                  |                  |
| **Financial Assets:**                                              |                  |                  |
| Unobservable inputs (as a percent)                                 | 0.0980                | 0.0954                |
| Level 3 | Mortgage servicing | Minimum | CPR                       |                  |                  |
| **Financial Assets:**                                              |                  |                  |
| Unobservable inputs (as a percent)                                 | 0.0000                | 0.0000                |
| Level 3 | Mortgage servicing | Maximum | CPR                       |                  |                  |
| **Financial Assets:**                                              |                  |                  |
| Unobservable inputs (as a percent)                                 | 1.0000                | 1.0000                |
| Level 3 | Mortgage servicing | Weighted Average | CPR              |                  |                  |
| **Financial Assets:**                                              |                  |                  |
| Unobservable inputs (as a percent)                                 | 0.0745                | 0.0756                |

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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.
+ References
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| - Definition
Value of input used to measure servicing asset.
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