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Impaired Loans (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016
Summary of the impaired loans by portfolio class of loans |  |
Loans with a Specific Valuation Allowance, Recorded Balance | $ 17,689 | $ 22,128
Loans with a Specific Valuation Allowance, Unpaid Principal Balance | 18,400 | 22,374
Specific valuation allowance | 5,223 | 6,881
Loans with a Specific Valuation Allowance, Average Balance | 18,986 | 26,745
Loans without a Specific Valuation Allowance, Recorded Balance | 102,305 | 108,135
Loans without a Specific Valuation Allowance, Unpaid Principal Balance | 122,833 | 131,059
Loans without a Specific Valuation Allowance, Average Balance | 107,945 | 108,827
Recorded balance | 119,994 | 130,263
Unpaid principal balance | 141,233 | 153,433
Average balance | 126,931 | 135,572
Residential Real Estate | Residential Real Estate |  |
Summary of the impaired loans by portfolio class of loans |  |
Loans with a Specific Valuation Allowance, Recorded Balance | 2,978 | 2,759
Loans with a Specific Valuation Allowance, Unpaid Principal Balance | 3,046 | 2,825
Specific valuation allowance | 246 | 856
Loans with a Specific Valuation Allowance, Average Balance | 2,928 | 4,942
Loans without a Specific Valuation Allowance, Recorded Balance | 9,421 | 8,853
Loans without a Specific Valuation Allowance, Unpaid Principal Balance | 10,380 | 9,925
Loans without a Specific Valuation Allowance, Average Balance | 9,834 | 12,858
Recorded balance | 12,399 | 11,612
Unpaid principal balance | 13,426 | 12,750
Average balance | 12,762 | 17,800
Commercial | Commercial Real Estate |  |
Summary of the impaired loans by portfolio class of loans |  |
Loans with a Specific Valuation Allowance, Recorded Balance | 4,545 | 9,129
Loans with a Specific Valuation Allowance, Unpaid Principal Balance | 4,573 | 9,130
Specific valuation allowance | 500 | 922
Loans with a Specific Valuation Allowance, Average Balance | 5,851 | 10,441
Loans without a Specific Valuation Allowance, Recorded Balance | 72,991 | 76,505
Loans without a Specific Valuation Allowance, Unpaid Principal Balance | 89,839 | 94,180
Loans without a Specific Valuation Allowance, Average Balance | 76,427 | 72,323
Recorded balance | 77,536 | 85,634
Unpaid principal balance | 94,412 | 103,310
Average balance | 82,278 | 82,764
Commercial | Other Commercial |  |
Summary of the impaired loans by portfolio class of loans |  |
Loans with a Specific Valuation Allowance, Recorded Balance | 8,183 | 8,814
Loans with a Specific Valuation Allowance, Unpaid Principal Balance | 8,378 | 8,929
Specific valuation allowance | 3,851 | 4,419
Loans with a Specific Valuation Allowance, Average Balance | 8,477 | 9,840
Loans without a Specific Valuation Allowance, Recorded Balance | 14,849 | 15,136
Loans without a Specific Valuation Allowance, Unpaid Principal Balance | 16,931 | 17,724
Loans without a Specific Valuation Allowance, Average Balance | 15,129 | 15,537
Recorded balance | 23,032 | 23,950
Unpaid principal balance | 25,309 | 26,653
Average balance | 23,606 | 25,377
Consumer and Other | Home Equity |  |
Summary of the impaired loans by portfolio class of loans |  |
Loans with a Specific Valuation Allowance, Recorded Balance | 186 | 334
Loans with a Specific Valuation Allowance, Unpaid Principal Balance | 199 | 345
Specific valuation allowance | 56 | 296
Loans with a Specific Valuation Allowance, Average Balance | 359 | 257
Loans without a Specific Valuation Allowance, Recorded Balance | 3,569 | 5,600
Loans without a Specific Valuation Allowance, Unpaid Principal Balance | 4,098 | 7,120
Loans without a Specific Valuation Allowance, Average Balance | 4,734 | 6,004
Recorded balance | 3,755 | 5,934
Unpaid principal balance | 4,297 | 7,465
Average balance | 5,093 | 6,261
Consumer and Other | Other Consumer |  |
Summary of the impaired loans by portfolio class of loans |  |
Loans with a Specific Valuation Allowance, Recorded Balance | 1,797 | 1,092
Loans with a Specific Valuation Allowance, Unpaid Principal Balance | 2,204 | 1,145
Specific valuation allowance | 570 | 388
Loans with a Specific Valuation Allowance, Average Balance | 1,371 | 1,265
Loans without a Specific Valuation Allowance, Recorded Balance | 1,475 | 2,041
Loans without a Specific Valuation Allowance, Unpaid Principal Balance | 1,585 | 2,110
Loans without a Specific Valuation Allowance, Average Balance | 1,821 | 2,105
Recorded balance | 3,272 | 3,133
Unpaid principal balance | 3,789 | 3,255
Average balance | $ 3,192 | $ 3,370

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