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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) $ in Thousands |  | 12 Months Ended |  |
--- | --- | --- | --- | ---
Jan. 29, 2018 USD ($) shares | Dec. 31, 2017 USD ($) subsidary location | Mar. 31, 2018 USD ($) | Dec. 31, 2016 USD ($)
Property, Plant and Equipment [Line Items] |  |  |  |
Number of subsidiaries | subsidary |  | 5 |  |
Goodwill impairment |  | $ 0 |  |
Total assets |  | 1,962,624 |  | $ 1,828,336
Loans, net |  | 1,347,779 |  | 1,233,651
Total deposits |  | $ 1,676,320 |  | $ 1,576,791
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 |  |
Forecast | Accumulated Other Comprehensive Loss | Accounting Standards Update 2018-02 |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |
Cumulative effect of new accounting principle in period of adoption |  |  | $ (487) |
Forecast | Retained Earnings | Accounting Standards Update 2018-02 |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |
Cumulative effect of new accounting principle in period of adoption |  |  | $ 487 |
Westbound Bank |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |
Total assets |  | $ 228,000 |  |
Loans, net |  | 160,300 |  |
Total deposits |  | $ 188,500 |  |
Westbound Bank |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |
Number of branch locations acquired | location |  | 4 |  |
Subsequent Event | Westbound Bank |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |
Equity interests issued (in shares) | shares | 900,000 |  |  |
Consideration paid | $ 6,400 |  |  |

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