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Fair Value Measurements - Assets Measured at Fair Value on Nonrecurring Basis by Significant Unobservable Inputs (Details) - Fair Value, Measurements, Nonrecurring | Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($)
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Liabilities measured at fair value on nonrecurring basis | $ 0 | $ 0
Level 3 |  |
ASSETS |  |
Total Assets | 74,917,000 | 43,062,000
Collateral method | Level 3 |  |
ASSETS |  |
Loans individually evaluated | 67,402,000 | 38,697,000
Other real estate owned | 1,953,000 | 3,231,000
Loans held for sale | 586,000 |
Discount rate | Level 3 |  |
ASSETS |  |
Mortgage servicing rights | $ 4,976,000 | $ 1,134,000
Costs to sell | Collateral method | Level 3 |  |
ASSETS |  |
Other real estate owned, measurement input |  | 0.0700
Minimum | Appraisal adjustment | Collateral method | Level 3 |  |
ASSETS |  |
Loans held for investment, measurement input | 0 | 0
Minimum | Discount rate | Discount rate | Level 3 |  |
ASSETS |  |
Loans held for investment, measurement input |  | 0.0475
Mortgage servicing rights, measurement input | 0.0924 | 0.0939
Minimum | Costs to sell | Collateral method | Level 3 |  |
ASSETS |  |
Other real estate owned, measurement input | 0.04 |
Minimum | Constant prepayment rates | Discount rate | Level 3 |  |
ASSETS |  |
Mortgage servicing rights, measurement input | 0.0882 | 0.0746
Maximum | Appraisal adjustment | Collateral method | Level 3 |  |
ASSETS |  |
Loans held for investment, measurement input | 0.47 | 0.20
Maximum | Discount rate | Discount rate | Level 3 |  |
ASSETS |  |
Loans held for investment, measurement input |  | 0.0550
Mortgage servicing rights, measurement input | 0.1255 | 0.1254
Maximum | Costs to sell | Collateral method | Level 3 |  |
ASSETS |  |
Other real estate owned, measurement input | 0.0700 |
Maximum | Constant prepayment rates | Discount rate | Level 3 |  |
ASSETS |  |
Mortgage servicing rights, measurement input | 0.1458 | 0.1274
Weighted Average | Appraisal adjustment | Collateral method | Level 3 |  |
ASSETS |  |
Loans held for investment, measurement input | 0.1690 | 0.0855
Weighted Average | Discount rate | Discount rate | Level 3 |  |
ASSETS |  |
Loans held for investment, measurement input |  | 0.0528
Mortgage servicing rights, measurement input | 0.0942 | 0.0949
Weighted Average | Costs to sell | Collateral method | Level 3 |  |
ASSETS |  |
Other real estate owned, measurement input | 0.0492 | 0.0700
Weighted Average | Constant prepayment rates | Discount rate | Level 3 |  |
ASSETS |  |
Mortgage servicing rights, measurement input | 0.1337 | 0.0973

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