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LOANS AND ALLOWANCE FOR LOAN LOSSES - Impaired Loans (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Unpaid Principal Balance |  |  |
Total | $ 14,094 | $ 12,852 |
Recorded Investment |  |  |
Total | 13,926 | 11,926 |
Allowance for Loan Losses Allocated | 5,937 | 876 |
Average Recorded Investment |  |  |
With no related allowance recorded | 12,699 | 13,735 | $ 15,451
Interest Income Recognized |  |  |
With no related allowance recorded | 154 | 312 | 444
Residential Mortgages |  |  |
Unpaid Principal Balance |  |  |
With no related allowance recorded | 450 | 395 |
Recorded Investment |  |  |
With no related allowance recorded | 427 | 396 |
Average Recorded Investment |  |  |
With no related allowance recorded | 418 | 366 | 244
Interest Income Recognized |  |  |
With no related allowance recorded | 8 | 5 | 4
Construction | Commercial mortgages: |  |  |
Unpaid Principal Balance |  |  |
With no related allowance recorded | 364 | 277 |
Recorded Investment |  |  |
With no related allowance recorded | 365 | 278 |
Average Recorded Investment |  |  |
With no related allowance recorded | 830 | 320 | 992
Interest Income Recognized |  |  |
With no related allowance recorded | 12 | 14 | 36
Commercial mortgages | Commercial mortgages: |  |  |
Unpaid Principal Balance |  |  |
With no related allowance recorded | 4,135 | 8,792 |
With an allowance recorded | 2,989 | 2,245 |
Recorded Investment |  |  |
With no related allowance recorded | 4,138 | 7,857 |
With an allowance recorded | 2,799 | 2,247 |
Allowance for Loan Losses Allocated | 802 | 735 |
Average Recorded Investment |  |  |
With no related allowance recorded | 5,606 | 6,793 | 7,728
With an allowance recorded | 3,751 | 4,749 | 4,503
Interest Income Recognized |  |  |
With no related allowance recorded | 78 | 240 | 264
With an allowance recorded | 12 | 6 | 49
Home equity lines and loans | Consumer Loans |  |  |
Unpaid Principal Balance |  |  |
With no related allowance recorded | 64 | 93 |
With an allowance recorded | 0 | 360 |
Recorded Investment |  |  |
With no related allowance recorded | 64 | 95 |
With an allowance recorded | 0 | 360 |
Allowance for Loan Losses Allocated | 0 | 141 |
Average Recorded Investment |  |  |
With no related allowance recorded | 74 | 102 | 396
With an allowance recorded | 144 | 362 | 84
Interest Income Recognized |  |  |
With no related allowance recorded | 3 | 5 | 6
With an allowance recorded | 0 | 0 | 18
Commercial and industrial | Commercial, and Agricultural |  |  |
Unpaid Principal Balance |  |  |
With no related allowance recorded | 861 | 690 |
With an allowance recorded | 5,231 | 0 |
Recorded Investment |  |  |
With no related allowance recorded | 867 | 693 |
With an allowance recorded | 5,266 | 0 |
Allowance for Loan Losses Allocated | 5,135 | 0 |
Average Recorded Investment |  |  |
With no related allowance recorded | 706 | 1,010 | 1,358
With an allowance recorded | 1,170 | 33 | 146
Interest Income Recognized |  |  |
With no related allowance recorded | 35 | 42 | 64
With an allowance recorded | $ 6 | $ 0 | $ 3

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