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LOANS AND ALLOWANCE FOR LOAN LOSSES - Troubled Debt Restructuring (Details) | 3 Months Ended |
--- | --- | ---
Mar. 31, 2018 USD ($) loan | Mar. 31, 2017 USD ($) loan | Dec. 31, 2017 USD ($)
Troubled Debt Restructurings [Abstract] |  |  |
Recorded investment in troubled debt restructurings | $ 7,300,000 |  | $ 7,700,000
Troubled debt restructuring reserve | 500,000 |  | 700,000
Troubled debt restructurings accruing interest under modified terms | 1,500,000 |  | 1,700,000
Troubled debt restructurings on non-accrual status | 5,800,000 |  | 6,000,000
Additional amounts committed to customers with loans classified as troubled debt restructurings | $ 0 |  | $ 0
Number of loans | 0 | 0 |
Increase (decrease) in allowance for loan losses |  | $ 0 |
TDR charge-offs | $ 0 | $ 0 |
Loans by class modified as troubled debt restructurings [Abstract] |  |  |
Number of loans | loan | 1 | 1 |
Pre-modification outstanding recorded investment | $ 100,000 | $ 166,000 |
Post-modification outstanding recorded investment | $ 100,000 | $ 166,000 |
Commercial and industrial |  |  |
Troubled Debt Restructurings [Abstract] |  |  |
Number of loans | loan | 1 |  |
Commercial and industrial | Commercial and agricultural: |  |  |
Loans by class modified as troubled debt restructurings [Abstract] |  |  |
Number of loans | loan | 1 |  |
Pre-modification outstanding recorded investment | $ 100,000 |  |
Post-modification outstanding recorded investment | $ 100,000 |  |
Commercial mortgages |  |  |
Troubled Debt Restructurings [Abstract] |  |  |
Number of loans | loan |  | 1 |
Commercial mortgages | Commercial Mortgages |  |  |
Loans by class modified as troubled debt restructurings [Abstract] |  |  |
Number of loans | loan |  | 1 |
Pre-modification outstanding recorded investment |  | $ 166,000 |
Post-modification outstanding recorded investment |  | $ 166,000 |

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- Definition The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings and are on nonaccrual status as of the balance sheet date. + References No definition available. + Details
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- Definition The increase (decrease) in the allowance for credit losses related to financing receivables. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524 + Details
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- Definition Post-modification amount of investment in financing receivables modified by troubled debt restructurings. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524 + Details
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