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Allowance for Loan Losses and Credit Quality of Loans, Impaired Loans (Details) - USD ($) $ in Thousands | 3 Months Ended |
--- | --- | ---
Mar. 31, 2017 | Mar. 31, 2016 | Dec. 31, 2016
Allowance for Loan Losses and Credit Quality of Loans [Abstract] |  |  |
Threshold balance for classified loans to be evaluated individually for impairment | $ 800 |  |
With an allowance recorded [Abstract] |  |  |
Recorded investment balance (book) | 25,309 |  | $ 28,874
Unpaid principal balance (legal) | 27,351 |  | 31,582
Related allowance | 422 |  | 1,517
Average recorded investment | 25,672 | $ 33,374 |
Interest income recognized | 206 | 324 |
Originated Loans [Member] |  |  |
With no related allowance recorded [Abstract] |  |  |
Recorded investment balance (book) | 24,141 |  | 21,912
Unpaid principal balance (legal) | 26,183 |  | 24,321
With an allowance recorded [Abstract] |  |  |
Average recorded investment | 25,371 | 32,169 |
Interest income recognized | 206 | 324 |
Originated Loans [Member] | Commercial Loans [Member] |  |  |
With no related allowance recorded [Abstract] |  |  |
Recorded investment balance (book) | 9,568 |  | 7,313
Unpaid principal balance (legal) | 9,868 |  | 7,970
With an allowance recorded [Abstract] |  |  |
Recorded investment balance (book) | 1,168 |  | 5,757
Unpaid principal balance (legal) | 1,168 |  | 5,940
Related allowance | 422 |  | 826
Originated Loans [Member] | Commercial Loans [Member] | Commercial [Member] |  |  |
With no related allowance recorded [Abstract] |  |  |
Recorded investment balance (book) | 3,495 |  | 1,278
Unpaid principal balance (legal) | 3,536 |  | 1,697
With an allowance recorded [Abstract] |  |  |
Average recorded investment | 2,926 | 2,773 |
Interest income recognized | 0 | 19 |
Originated Loans [Member] | Commercial Loans [Member] | Commercial Real Estate [Member] |  |  |
With no related allowance recorded [Abstract] |  |  |
Recorded investment balance (book) | 3,778 |  | 3,816
Unpaid principal balance (legal) | 3,810 |  | 3,841
With an allowance recorded [Abstract] |  |  |
Recorded investment balance (book) | 1,081 |  | 5,553
Unpaid principal balance (legal) | 1,081 |  | 5,736
Related allowance | 335 |  | 735
Average recorded investment | 5,995 | 13,509 |
Interest income recognized | 44 | 100 |
Originated Loans [Member] | Commercial Loans [Member] | Agricultural [Member] |  |  |
With no related allowance recorded [Abstract] |  |  |
Recorded investment balance (book) | 130 |  | 130
Unpaid principal balance (legal) | 138 |  | 137
With an allowance recorded [Abstract] |  |  |
Recorded investment balance (book) | 37 |  | 49
Unpaid principal balance (legal) | 37 |  | 49
Related allowance | 37 |  | 37
Average recorded investment | 173 | 158 |
Interest income recognized | 0 | 0 |
Originated Loans [Member] | Commercial Loans [Member] | Agricultural Real Estate [Member] |  |  |
With no related allowance recorded [Abstract] |  |  |
Recorded investment balance (book) | 1,520 |  | 1,434
Unpaid principal balance (legal) | 1,660 |  | 1,567
With an allowance recorded [Abstract] |  |  |
Recorded investment balance (book) | 50 |  | 155
Unpaid principal balance (legal) | 50 |  | 155
Related allowance | 50 |  | 54
Average recorded investment | 1,580 | 616 |
Interest income recognized | 11 | 11 |
Originated Loans [Member] | Commercial Loans [Member] | Business Banking [Member] |  |  |
With no related allowance recorded [Abstract] |  |  |
Recorded investment balance (book) | 645 |  | 655
Unpaid principal balance (legal) | 724 |  | 728
With an allowance recorded [Abstract] |  |  |
Average recorded investment | 650 | 978 |
Interest income recognized | 2 | 6 |
Originated Loans [Member] | Consumer Loans [Member] |  |  |
With no related allowance recorded [Abstract] |  |  |
Recorded investment balance (book) | 8,379 |  | 8,488
Unpaid principal balance (legal) | 9,287 |  | 9,445
Originated Loans [Member] | Consumer Loans [Member] | Indirect [Member] |  |  |
With no related allowance recorded [Abstract] |  |  |
Recorded investment balance (book) | 5 |  | 5
Unpaid principal balance (legal) | 15 |  | 16
With an allowance recorded [Abstract] |  |  |
Average recorded investment | 5 | 11 |
Interest income recognized | 0 | 0 |
Originated Loans [Member] | Consumer Loans [Member] | Home Equity [Member] |  |  |
With no related allowance recorded [Abstract] |  |  |
Recorded investment balance (book) | 8,374 |  | 8,483
Unpaid principal balance (legal) | 9,272 |  | 9,429
With an allowance recorded [Abstract] |  |  |
Average recorded investment | 8,431 | 8,003 |
Interest income recognized | 110 | 121 |
Originated Loans [Member] | Residential Real Estate Mortgages [Member] |  |  |
With no related allowance recorded [Abstract] |  |  |
Recorded investment balance (book) | 6,194 |  | 6,111
Unpaid principal balance (legal) | 7,028 |  | 6,906
With an allowance recorded [Abstract] |  |  |
Average recorded investment | 5,611 | 6,121 |
Interest income recognized | 39 | 67 |
Acquired Loans [Member] |  |  |
With an allowance recorded [Abstract] |  |  |
Average recorded investment | 301 | 1,205 |
Interest income recognized | 0 | 0 |
Acquired Loans [Member] | Commercial Loans [Member] |  |  |
With an allowance recorded [Abstract] |  |  |
Recorded investment balance (book) | 0 |  | 1,205
Unpaid principal balance (legal) | 0 |  | 1,321
Related allowance | 0 |  | 691
Acquired Loans [Member] | Commercial Loans [Member] | Commercial Real Estate [Member] |  |  |
With an allowance recorded [Abstract] |  |  |
Recorded investment balance (book) | 0 |  | 1,205
Unpaid principal balance (legal) | 0 |  | 1,321
Related allowance | 0 |  | $ 691
Average recorded investment | 301 | 1,205 |
Interest income recognized | $ 0 | $ 0 |

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