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LOANS AND ALLOWANCE FOR LOAN LOSSES - Credit Quality Indicator (Details) - USD ($) | 3 Months Ended |  |
--- | --- | --- | ---
Mar. 31, 2017 | Mar. 31, 2018 | Dec. 31, 2017
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | $ 1,323,529,000 | $ 1,315,582,000
Deteriorated Loans Transferred in [Abstract] |  |  |
Allowance for loan and lease loss, recovery of bad debts | $ 0 |  |
Loans acquired with deteriorated credit quality |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 0 | 792,000
Not Rated |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 467,690,000 | 464,414,000
Pass |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 807,453,000 | 807,976,000
Special Mention |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 20,289,000 | 14,112,000
Substandard |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 21,737,000 | 25,489,000
Doubtful |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 6,360,000 | 2,799,000
Commercial and agricultural: |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 201,037,000 | 199,576,000
Commercial and agricultural: | Loans acquired with deteriorated credit quality |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  |  | 0
Commercial Mortgages |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 649,413,000 | 646,174,000
Commercial Mortgages | Loans acquired with deteriorated credit quality |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  |  | 792,000
Commercial Mortgages | Construction |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 55,560,000 | 45,688,000
Commercial Mortgages | Construction | Loans acquired with deteriorated credit quality |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 0 | 0
Commercial Mortgages | Construction | Not Rated |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 0 | 0
Commercial Mortgages | Construction | Pass |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 55,430,000 | 45,553,000
Commercial Mortgages | Construction | Special Mention |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 0 | 0
Commercial Mortgages | Construction | Substandard |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 130,000 | 135,000
Commercial Mortgages | Construction | Doubtful |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 0 | 0
Commercial Mortgages | Commercial mortgages |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 593,853,000 | 600,486,000
Commercial Mortgages | Commercial mortgages | Loans acquired with deteriorated credit quality |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 0 | 792,000
Commercial Mortgages | Commercial mortgages | Not Rated |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 0 | 0
Commercial Mortgages | Commercial mortgages | Pass |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 567,624,000 | 575,321,000
Commercial Mortgages | Commercial mortgages | Special Mention |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 11,570,000 | 9,665,000
Commercial Mortgages | Commercial mortgages | Substandard |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 13,307,000 | 13,331,000
Commercial Mortgages | Commercial mortgages | Doubtful |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 1,352,000 | 1,377,000
Residential mortgages |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 195,096,000 | 194,937,000
Residential and consumer finance receivable [Abstract] |  |  |
Residential and consumer loans receivable |  | 195,096,000 | 194,937,000
Residential mortgages | Loans acquired with deteriorated credit quality |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 0 | 0
Residential mortgages | Performing |  |  |
Residential and consumer finance receivable [Abstract] |  |  |
Residential and consumer loans receivable |  | 191,941,000 | 191,777,000
Residential mortgages | Non-Performing |  |  |
Residential and consumer finance receivable [Abstract] |  |  |
Residential and consumer loans receivable |  | 3,155,000 | 3,160,000
Residential mortgages | Not Rated |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 191,941,000 | 191,777,000
Residential mortgages | Pass |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 0 | 0
Residential mortgages | Special Mention |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 0 | 0
Residential mortgages | Substandard |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 3,155,000 | 3,160,000
Residential mortgages | Doubtful |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 0 | 0
Consumer loans: |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 277,983,000 | 274,895,000
Consumer loans: | Loans acquired with deteriorated credit quality |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  |  | 0
Consumer loans: | Credit cards |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 1,418,000 | 1,516,000
Residential and consumer finance receivable [Abstract] |  |  |
Residential and consumer loans receivable |  | 1,418,000 | 1,516,000
Consumer loans: | Credit cards | Loans acquired with deteriorated credit quality |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 0 | 0
Consumer loans: | Credit cards | Performing |  |  |
Residential and consumer finance receivable [Abstract] |  |  |
Residential and consumer loans receivable |  | 1,418,000 | 1,516,000
Consumer loans: | Credit cards | Non-Performing |  |  |
Residential and consumer finance receivable [Abstract] |  |  |
Residential and consumer loans receivable |  | 0 | 0
Consumer loans: | Credit cards | Not Rated |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 1,418,000 | 1,516,000
Consumer loans: | Credit cards | Pass |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 0 | 0
Consumer loans: | Credit cards | Special Mention |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 0 | 0
Consumer loans: | Credit cards | Substandard |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 0 | 0
Consumer loans: | Credit cards | Doubtful |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 0 | 0
Consumer loans: | Home equity lines and loans |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 100,902,000 | 100,878,000
Residential and consumer finance receivable [Abstract] |  |  |
Residential and consumer loans receivable |  | 100,902,000 | 100,878,000
Consumer loans: | Home equity lines and loans | Loans acquired with deteriorated credit quality |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 0 | 0
Consumer loans: | Home equity lines and loans | Performing |  |  |
Residential and consumer finance receivable [Abstract] |  |  |
Residential and consumer loans receivable |  | 99,600,000 | 99,568,000
Consumer loans: | Home equity lines and loans | Non-Performing |  |  |
Residential and consumer finance receivable [Abstract] |  |  |
Residential and consumer loans receivable |  | 1,302,000 | 1,310,000
Consumer loans: | Home equity lines and loans | Not Rated |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 99,600,000 | 99,568,000
Consumer loans: | Home equity lines and loans | Pass |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 0 | 0
Consumer loans: | Home equity lines and loans | Special Mention |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 0 | 0
Consumer loans: | Home equity lines and loans | Substandard |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 1,302,000 | 1,310,000
Consumer loans: | Home equity lines and loans | Doubtful |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 0 | 0
Consumer loans: | Indirect consumer loans |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 157,340,000 | 153,532,000
Residential and consumer finance receivable [Abstract] |  |  |
Residential and consumer loans receivable |  | 157,340,000 | 153,532,000
Consumer loans: | Indirect consumer loans | Loans acquired with deteriorated credit quality |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 0 | 0
Consumer loans: | Indirect consumer loans | Performing |  |  |
Residential and consumer finance receivable [Abstract] |  |  |
Residential and consumer loans receivable |  | 156,454,000 | 152,598,000
Consumer loans: | Indirect consumer loans | Non-Performing |  |  |
Residential and consumer finance receivable [Abstract] |  |  |
Residential and consumer loans receivable |  | 886,000 | 934,000
Consumer loans: | Indirect consumer loans | Not Rated |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 156,454,000 | 152,598,000
Consumer loans: | Indirect consumer loans | Pass |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 0 | 0
Consumer loans: | Indirect consumer loans | Special Mention |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 0 | 0
Consumer loans: | Indirect consumer loans | Substandard |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 886,000 | 934,000
Consumer loans: | Indirect consumer loans | Doubtful |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 0 | 0
Consumer loans: | Direct consumer loans |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 18,323,000 | 18,969,000
Residential and consumer finance receivable [Abstract] |  |  |
Residential and consumer loans receivable |  | 18,323,000 | 18,969,000
Consumer loans: | Direct consumer loans | Loans acquired with deteriorated credit quality |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 0 | 0
Consumer loans: | Direct consumer loans | Performing |  |  |
Residential and consumer finance receivable [Abstract] |  |  |
Residential and consumer loans receivable |  | 18,277,000 | 18,955,000
Consumer loans: | Direct consumer loans | Non-Performing |  |  |
Residential and consumer finance receivable [Abstract] |  |  |
Residential and consumer loans receivable |  | 46,000 | 14,000
Consumer loans: | Direct consumer loans | Not Rated |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 18,277,000 | 18,955,000
Consumer loans: | Direct consumer loans | Pass |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 0 | 0
Consumer loans: | Direct consumer loans | Special Mention |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 0 | 0
Consumer loans: | Direct consumer loans | Substandard |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 46,000 | 14,000
Consumer loans: | Direct consumer loans | Doubtful |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 0 | 0
Commercial and industrial | Commercial and agricultural: |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 200,507,000 | 199,030,000
Commercial and industrial | Commercial and agricultural: | Loans acquired with deteriorated credit quality |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 0 | 0
Commercial and industrial | Commercial and agricultural: | Not Rated |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 0 | 0
Commercial and industrial | Commercial and agricultural: | Pass |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 183,869,000 | 186,556,000
Commercial and industrial | Commercial and agricultural: | Special Mention |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 8,719,000 | 4,447,000
Commercial and industrial | Commercial and agricultural: | Substandard |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 2,911,000 | 6,605,000
Commercial and industrial | Commercial and agricultural: | Doubtful |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 5,008,000 | 1,422,000
Agricultural | Commercial and agricultural: |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 530,000 | 546,000
Agricultural | Commercial and agricultural: | Loans acquired with deteriorated credit quality |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 0 | 0
Agricultural | Commercial and agricultural: | Not Rated |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 0 | 0
Agricultural | Commercial and agricultural: | Pass |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 530,000 | 546,000
Agricultural | Commercial and agricultural: | Special Mention |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 0 | 0
Agricultural | Commercial and agricultural: | Substandard |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | 0 | 0
Agricultural | Commercial and agricultural: | Doubtful |  |  |
Finance receivable by credit quality indicator [Abstract] |  |  |
Loans |  | $ 0 | $ 0

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