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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Narrative (Details) |  |  |  | 12 Months Ended |  |
--- | --- | --- | --- | --- | --- | ---
Mar. 04, 2022 USD ($) | Mar. 16, 2020 | Jan. 01, 2020 USD ($) | Dec. 31, 2021 USD ($) Segment Family ResidentialHouse | Dec. 31, 2020 USD ($) | Mar. 09, 2022 $ / shares | Mar. 27, 2020 USD ($)
Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |
Number of families secured by loans of real estate | Family |  |  |  | 4 |  |  |
Number of housing units secured by loans from segment | ResidentialHouse |  |  |  | 5 |  |  |
Goodwill impairment |  |  |  | $ 0 |  |  |
Number of operating segments | Segment |  |  |  | 1 |  |  |
Number of reportable operating segments | Segment |  |  |  | 1 |  |  |
Impact of adoption of ASC 326, tax |  |  |  |  | $ 955,000 |  |
Decrease to retained earnings |  |  |  | $ 107,645,000 | $ 113,449,000 |  |
Subsequent Event [Member] |  |  |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |
Subordinated notes | $ 35,000,000 |  |  |  |  |  |
Notes, maturity date | Apr. 01, 2032 |  |  |  |  |  |
Stated annual interest rate | 3.625% |  |  |  |  |  |
Cash dividend per share | $ / shares |  |  |  |  |  | $ 0.22 |
Core Deposits [Member] |  |  |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |
Core deposit amortization period |  |  |  | 10 years |  |  |
Paycheck Protection Program Loans |  |  |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |
Percentage of government guaranteed loans |  |  |  | 100.00% |  |  |
Accounting Standards Update 2016-13 |  |  |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |
Change in Accounting Principle, Accounting Standards Update, Adoption Date |  |  |  | Jan. 01, 2020 |  |  |
Increase to allowance for credit losses |  |  | $ 4,548,000 |  |  |  |
Increase to allowance for credit losses, percent |  |  | 28.10% |  |  |  |
Accounting Standards Update 2016-13 | Cumulative Effect, Period of Adoption, Adjustment [Member] | Restatement Adjustment [Member] |  |  |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |
Impact of adoption of ASC 326, tax |  |  | $ 955,000 |  |  |  |
Decrease to retained earnings |  |  | $ 3,593,000 |  |  |  |
COVID-19 |  |  |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |
Maximum authorized amount of coronavirus aid, relief and economic security |  |  |  |  |  |  | $ 2,000,000,000,000
Description of federal fund interest rate |  |  |  | Due to the COVID-19 pandemic, market interest rates declined significantly, with the 10-year Treasury bond falling below 1.00% on March 3, 2020 for the first time. On March 16, 2020, the Federal Open Market Committee reduced the target federal funds rate range to 0.00% to 0.25%, at which it remains as of December 31, 2021. |  |  |
COVID-19 | Minimum |  |  |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |
Federal open market committee reduced target federal funds interest rate. |  | 0.00% |  |  |  |  |
COVID-19 | Maximum |  |  |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |
Federal open market committee reduced target federal funds interest rate. |  | 0.25% |  |  |  |  |

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