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MORTGAGE BANKING OPERATIONS - Sensitivity Analysis (Details) $ in Thousands | 9 Months Ended |
--- | --- | ---
Sep. 30, 2021 USD ($) | Dec. 31, 2020
Key economic assumptions and the sensitivity of the current fair value for single family MSRs |  |
Fair value of single family MSR | $ 61,206 |
Expected weighted-average life (in years) | 5 years 10 months 13 days |
Constant Prepayment Rate [Abstract] |  |
Impact on fair value of 25 basis points adverse change in interest rates | $ (3,490) |
Impact on fair value of 50 basis points adverse change in interest rates | (7,016) |
Discount Rate [Abstract] |  |
Impact on fair value of 100 basis points increase | (2,949) |
Impact on fair value of 200 basis points increase | $ (5,675) |
Minimum | CPRs |  |
Key economic assumptions and the sensitivity of the current fair value for single family MSRs |  |
Measurement input (as a percent) | 0.0798 | 0.0813
Minimum | Discount rate |  |
Key economic assumptions and the sensitivity of the current fair value for single family MSRs |  |
Measurement input (as a percent) | 0.0654 | 0.0650
Maximum | CPRs |  |
Key economic assumptions and the sensitivity of the current fair value for single family MSRs |  |
Measurement input (as a percent) | 0.1743 | 0.1970
Maximum | Discount rate |  |
Key economic assumptions and the sensitivity of the current fair value for single family MSRs |  |
Measurement input (as a percent) | 0.1378 | 0.1314
Weighted average | CPRs |  |
Key economic assumptions and the sensitivity of the current fair value for single family MSRs |  |
Measurement input (as a percent) | 0.1074 | 0.1281
Weighted average | Discount rate |  |
Key economic assumptions and the sensitivity of the current fair value for single family MSRs |  |
Measurement input (as a percent) | 0.0784 | 0.0827

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