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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Narrative (Details) |  | 12 Months Ended |
--- | --- | --- | ---
Jan. 01, 2020 | Dec. 31, 2019 USD ($) subsidary Family Residentialhouse segment | Mar. 31, 2019 USD ($)
Property, Plant and Equipment [Line Items] |  |  |
Number of subsidiaries | subsidary |  | 6 |
Number of families secured by loans of real estate | Family |  | 4 |
Goodwill impairment |  | $ 0 |
Number of operating segments | segment |  | 1 |
Number of reportable operating segments | segment |  | 1 |
Operating lease right of use asset |  | $ 11,554,000 |
Operating lease liability |  | $ 11,675,000 |
Accounting Standards Update 2016-02 |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Operating lease right of use asset |  |  | $ 12,000,000.0
Operating lease liability |  |  | 12,000,000.0
Accumulated Other Comprehensive Loss | Accounting Standards Update 2018-02 |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Reclassification of certain tax effects from accumulated other comprehensive income |  |  | 486,000
Retained Earnings | Accounting Standards Update 2018-02 |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Reclassification of certain tax effects from accumulated other comprehensive income |  |  | $ 486,000
Core Deposits |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Core deposit amortization period |  | 10 years |
Maximum |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Number of housing units secured by loans from segment | Residentialhouse |  | 5 |
Maximum | Accounting Standards Update 2016-13 | Subsequent Event |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Increase to allowance for credit losses, percent | 30.00% |  |
Minimum | Accounting Standards Update 2016-13 | Subsequent Event |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Increase to allowance for credit losses, percent | 20.00% |  |

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