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LOAN SERVICING ACTIVITIES - Narrative (Details) - USD ($) $ in Thousands | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
LOAN SERVICING ACTIVITIES |  |  |  |
Principal balances outstanding | $ 9,244,661 | $ 5,622,044 |  |
Bank held borrowers' escrow balances | 2,900 | 3,900 |  |
Fair value of SRAs | $ 3,856 | $ 1,710 | $ 1,459 | $ 1,315
Weighted average default rate | 1.24 | 1.30 |  |
Real estate and C&I loans |  |  |  |
LOAN SERVICING ACTIVITIES |  |  |  |
Principal balances outstanding | $ 471,900 | $ 377,700 |  |
Minimum |  |  |  |
LOAN SERVICING ACTIVITIES |  |  |  |
Discount rates | 7.80% | 4.00% |  |
Prepayment speeds | 5.00% | 5.00% |  |
Maximum |  |  |  |
LOAN SERVICING ACTIVITIES |  |  |  |
Discount rates | 12.00% | 17.00% |  |
Prepayment speeds | 38.00% | 20.00% |  |

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