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Allowance for Loan Losses and Credit Quality of Loans, Impaired Loans (Details) - USD ($) $ in Thousands | 3 Months Ended |
--- | --- | ---
Mar. 31, 2016 | Mar. 31, 2015 | Dec. 31, 2015
Allowance for Loan Losses and Credit Quality of Loans [Abstract] |  |  |
Minimum balance for classified loans to be evaluated individually for impairment | $ 500 |  |
With an allowance recorded [Abstract] |  |  |
Recorded investment balance (book) | 35,372 |  | $ 27,168
Unpaid principal balance (legal) | 39,422 |  | 31,665
Related allowance | 2,970 |  | 2,005
Average recorded investment | 33,374 | $ 33,026 |
Interest income recognized | 324 | 183 |
Originated Loans [Member] |  |  |
With no related allowance recorded [Abstract] |  |  |
Recorded investment balance (book) | 26,323 |  | 21,296
Unpaid principal balance (legal) | 28,409 |  | 23,828
With an allowance recorded [Abstract] |  |  |
Average recorded investment | 32,169 | 23,007 |
Interest income recognized | 324 | 183 |
Originated Loans [Member] | Commercial Loans [Member] |  |  |
With no related allowance recorded [Abstract] |  |  |
Recorded investment balance (book) | 11,847 |  | 7,586
Unpaid principal balance (legal) | 12,293 |  | 8,606
With an allowance recorded [Abstract] |  |  |
Recorded investment balance (book) | 7,844 |  | 4,667
Unpaid principal balance (legal) | 9,692 |  | 6,516
Related allowance | 2,235 |  | 1,270
Originated Loans [Member] | Commercial Loans [Member] | Commercial [Member] |  |  |
With no related allowance recorded [Abstract] |  |  |
Recorded investment balance (book) | 2,334 |  | 2,244
Unpaid principal balance (legal) | 2,581 |  | 2,490
With an allowance recorded [Abstract] |  |  |
Recorded investment balance (book) | 453 |  | 457
Unpaid principal balance (legal) | 453 |  | 457
Related allowance | 325 |  | 300
Average recorded investment | 2,773 | 1,689 |
Interest income recognized | 19 | 25 |
Originated Loans [Member] | Commercial Loans [Member] | Commercial Real Estate [Member] |  |  |
With no related allowance recorded [Abstract] |  |  |
Recorded investment balance (book) | 7,910 |  | 3,165
Unpaid principal balance (legal) | 7,920 |  | 3,175
With an allowance recorded [Abstract] |  |  |
Recorded investment balance (book) | 7,391 |  | 4,210
Unpaid principal balance (legal) | 9,239 |  | 6,059
Related allowance | 1,910 |  | 970
Average recorded investment | 13,509 | 9,125 |
Interest income recognized | 100 | 41 |
Originated Loans [Member] | Commercial Loans [Member] | Agricultural [Member] |  |  |
With no related allowance recorded [Abstract] |  |  |
Recorded investment balance (book) | 18 |  | 576
Unpaid principal balance (legal) | 24 |  | 1,164
With an allowance recorded [Abstract] |  |  |
Average recorded investment | 158 | 20 |
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) | 613 |  | 618
Unpaid principal balance (legal) | 739 |  | 744
With an allowance recorded [Abstract] |  |  |
Average recorded investment | 616 | 636 |
Interest income recognized | 11 | 11 |
Originated Loans [Member] | Commercial Loans [Member] | Business Banking [Member] |  |  |
With no related allowance recorded [Abstract] |  |  |
Recorded investment balance (book) | 972 |  | 983
Unpaid principal balance (legal) | 1,029 |  | 1,033
With an allowance recorded [Abstract] |  |  |
Average recorded investment | 978 | 873 |
Interest income recognized | 6 | 4 |
Originated Loans [Member] | Consumer Loans [Member] |  |  |
With no related allowance recorded [Abstract] |  |  |
Recorded investment balance (book) | 8,262 |  | 7,693
Unpaid principal balance (legal) | 9,181 |  | 8,595
Originated Loans [Member] | Consumer Loans [Member] | Indirect [Member] |  |  |
With no related allowance recorded [Abstract] |  |  |
Recorded investment balance (book) | 10 |  | 12
Unpaid principal balance (legal) | 20 |  | 21
With an allowance recorded [Abstract] |  |  |
Average recorded investment | 11 | 9 |
Interest income recognized | 0 | 0 |
Originated Loans [Member] | Consumer Loans [Member] | Home Equity [Member] |  |  |
With no related allowance recorded [Abstract] |  |  |
Recorded investment balance (book) | 8,252 |  | 7,681
Unpaid principal balance (legal) | 9,161 |  | 8,574
With an allowance recorded [Abstract] |  |  |
Average recorded investment | 8,003 | 6,388 |
Interest income recognized | 121 | 72 |
Originated Loans [Member] | Consumer Loans [Member] | Direct [Member] |  |  |
With an allowance recorded [Abstract] |  |  |
Average recorded investment | 0 | 2 |
Interest income recognized | 0 | 0 |
Originated Loans [Member] | Residential Real Estate Mortgages [Member] |  |  |
With no related allowance recorded [Abstract] |  |  |
Recorded investment balance (book) | 6,214 |  | 6,017
Unpaid principal balance (legal) | 6,935 |  | 6,627
With an allowance recorded [Abstract] |  |  |
Average recorded investment | 6,121 | 4,265 |
Interest income recognized | 67 | 30 |
Acquired Loans [Member] |  |  |
With an allowance recorded [Abstract] |  |  |
Average recorded investment | 1,205 | 10,019 |
Interest income recognized | 0 | 0 |
Acquired Loans [Member] | Commercial Loans [Member] |  |  |
With an allowance recorded [Abstract] |  |  |
Recorded investment balance (book) | 1,205 |  | 1,205
Unpaid principal balance (legal) | 1,321 |  | 1,321
Related allowance | 735 |  | 735
Acquired Loans [Member] | Commercial Loans [Member] | Commercial [Member] |  |  |
With an allowance recorded [Abstract] |  |  |
Average recorded investment | 0 | 2,883 |
Interest income recognized | 0 | 0 |
Acquired Loans [Member] | Commercial Loans [Member] | Commercial Real Estate [Member] |  |  |
With an allowance recorded [Abstract] |  |  |
Recorded investment balance (book) | 1,205 |  | 1,205
Unpaid principal balance (legal) | 1,321 |  | 1,321
Related allowance | 735 |  | $ 735
Average recorded investment | 1,205 | 7,136 |
Interest income recognized | $ 0 | $ 0 |

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