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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2018 USD ($) subsidary segment | Mar. 31, 2019 USD ($)
Property, Plant and Equipment [Line Items] |  |
Number of subsidiaries | subsidary | 6 |
Goodwill impairment | $ 0 |
Number of reportable operating segments | segment | 1 |
Core Deposits |  |
Property, Plant and Equipment [Line Items] |  |
Core deposit amortization period | 10 years |
Maximum | Bank Buildings |  |
Property, Plant and Equipment [Line Items] |  |
Estimated useful life | 40 years |
Maximum | Equipment |  |
Property, Plant and Equipment [Line Items] |  |
Estimated useful life | 10 years |
Maximum | Furniture and Fixtures |  |
Property, Plant and Equipment [Line Items] |  |
Estimated useful life | 7 years |
Maximum | Software |  |
Property, Plant and Equipment [Line Items] |  |
Estimated useful life | 5 years |
Maximum | Automobiles |  |
Property, Plant and Equipment [Line Items] |  |
Estimated useful life | 4 years |
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 |
Expected impact | Accounting Standards Update 2016-02 |  |
Property, Plant and Equipment [Line Items] |  |
Expected increase to recorded assets |  | $ 12,000,000
Expected increase to recorded liabilities |  | $ 12,000,000

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