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LOANS AND ALLOWANCE FOR LOAN LOSSES - Impaired Loans (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Unpaid Principal Balance |  |  |
Total | $ 16,546 | $ 15,712 |
Recorded Investment |  |  |
Total | 10,589 | 15,665 |
Allowance for Loan Losses Allocated | 1,527 | 8,097 |
Average Recorded Investment |  |  |
With no related allowance recorded | 14,690 | 14,423 | $ 10,972
Interest Income Recognized |  |  |
With no related allowance recorded | 76 | 72 | 61
Residential Mortgages |  |  |
Unpaid Principal Balance |  |  |
With no related allowance recorded | 1,283 | 554 |
Recorded Investment |  |  |
With no related allowance recorded | 1,271 | 525 |
Average Recorded Investment |  |  |
With no related allowance recorded | 952 | 422 | 416
Interest Income Recognized |  |  |
With no related allowance recorded | 25 | 44 | 7
Construction | Commercial mortgages |  |  |
Unpaid Principal Balance |  |  |
With no related allowance recorded | 188 | 247 |
Recorded Investment |  |  |
With no related allowance recorded | 189 | 247 |
Average Recorded Investment |  |  |
With no related allowance recorded | 219 | 278 | 337
Interest Income Recognized |  |  |
With no related allowance recorded | 8 | 10 | 11
Commercial mortgages | Commercial mortgages |  |  |
Unpaid Principal Balance |  |  |
With no related allowance recorded | 6,814 | 3,501 |
With an allowance recorded | 258 | 5,093 |
Recorded Investment |  |  |
With no related allowance recorded | 4,760 | 3,503 |
With an allowance recorded | 168 | 5,094 |
Allowance for Loan Losses Allocated | 74 | 2,097 |
Average Recorded Investment |  |  |
With no related allowance recorded | 4,103 | 3,605 | 4,193
With an allowance recorded | 2,949 | 6,524 | 2,315
Interest Income Recognized |  |  |
With no related allowance recorded | 16 | 12 | 21
With an allowance recorded | 0 | 0 | 4
Home equity lines and loans | Consumer Loans |  |  |
Unpaid Principal Balance |  |  |
With no related allowance recorded | 645 | 171 |
With an allowance recorded | 170 | 0 |
Recorded Investment |  |  |
With no related allowance recorded | 631 | 149 |
With an allowance recorded | 170 | 0 |
Allowance for Loan Losses Allocated | 52 | 0 |
Average Recorded Investment |  |  |
With no related allowance recorded | 446 | 137 | 60
With an allowance recorded | 104 | 0 | 0
Interest Income Recognized |  |  |
With no related allowance recorded | 7 | 6 | 3
With an allowance recorded | 0 | 0 | 0
Commercial and industrial | Commercial and industrial |  |  |
Unpaid Principal Balance |  |  |
With no related allowance recorded | 1,960 | 133 |
With an allowance recorded | 5,228 | 6,013 |
Recorded Investment |  |  |
With no related allowance recorded | 1,963 | 133 |
With an allowance recorded | 1,437 | 6,014 |
Allowance for Loan Losses Allocated | 1,401 | 6,000 |
Average Recorded Investment |  |  |
With no related allowance recorded | 936 | 248 | 608
With an allowance recorded | 4,981 | 3,209 | 3,043
Interest Income Recognized |  |  |
With no related allowance recorded | 16 | 0 | 12
With an allowance recorded | $ 4 | $ 0 | $ 3

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