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Fair Value Measurements - Assets Measured at Fair Value on Nonrecurring Basis by Significant Unobservable Inputs (Details) - Fair Value, Measurements, Nonrecurring | Sep. 30, 2021 USD ($) | Dec. 31, 2020 USD ($)
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Liabilities measured at fair value on a nonrecurring basis | $ 0 | $ 0
Level 3 |  |
ASSETS |  |
Total Assets | 63,132,000 | 74,917,000
Collateral method | Level 3 |  |
ASSETS |  |
Loans individually evaluated | 41,135,000 | 67,402,000
Other real estate owned | 13,313,000 | 1,953,000
Discounted cash flow method | Level 3 |  |
ASSETS |  |
Mortgage servicing rights | 7,015,000 | 4,976,000
Contractual agreement | Level 3 |  |
ASSETS |  |
Loans held for sale | $ 1,669,000 | $ 586,000
Minimum | Appraisal adjustment | Collateral method | Level 3 |  |
ASSETS |  |
Loans held for investment, measurement input | 0 | 0
Minimum | Costs to sell | Collateral method | Level 3 |  |
ASSETS |  |
Other real estate owned, measurement input | 0.0400 | 0.0400
Minimum | Discount rate | Discounted cash flow method | Level 3 |  |
ASSETS |  |
Mortgage servicing rights, measurement input | 0.0921 | 0.0924
Minimum | Constant prepayment rates | Discounted cash flow method | Level 3 |  |
ASSETS |  |
Mortgage servicing rights, measurement input | 0.0793 | 0.0882
Maximum | Appraisal adjustment | Collateral method | Level 3 |  |
ASSETS |  |
Loans held for investment, measurement input | 0.1700 | 0.4700
Maximum | Costs to sell | Collateral method | Level 3 |  |
ASSETS |  |
Other real estate owned, measurement input | 0.0700 | 0.0700
Maximum | Discount rate | Discounted cash flow method | Level 3 |  |
ASSETS |  |
Mortgage servicing rights, measurement input | 0.1254 | 0.1255
Maximum | Constant prepayment rates | Discounted cash flow method | Level 3 |  |
ASSETS |  |
Mortgage servicing rights, measurement input | 0.1496 | 0.1458
Weighted Average | Appraisal adjustment | Collateral method | Level 3 |  |
ASSETS |  |
Loans held for investment, measurement input | 0.1368 | 0.1690
Weighted Average | Costs to sell | Collateral method | Level 3 |  |
ASSETS |  |
Other real estate owned, measurement input | 0.0677 | 0.0492
Weighted Average | Discount rate | Discounted cash flow method | Level 3 |  |
ASSETS |  |
Mortgage servicing rights, measurement input | 0.0938 | 0.0942
Weighted Average | Constant prepayment rates | Discounted cash flow method | Level 3 |  |
ASSETS |  |
Mortgage servicing rights, measurement input | 0.1069 | 0.1337

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