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Allowance for Loan Losses and Credit Quality of Loans, Average Recorded Investments on Loans Specifically Evaluated for Impairment and Interest Income Recognized (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2017 | Jun. 30, 2016 | Jun. 30, 2017 | Jun. 30, 2016
Financing Receivable, Impaired [Line Items] |  |  |  |
Average recorded investment | $ 24,508 | $ 35,641 | $ 25,446 | $ 34,382
Interest income recognized | 194 | 204 | 422 | 484
Originated Loans [Member] |  |  |  |
Financing Receivable, Impaired [Line Items] |  |  |  |
Average recorded investment | 24,508 | 34,436 | 25,274 | 33,177
Interest income recognized | 194 | 204 | 422 | 484
Originated Loans [Member] | Commercial Loans [Member] | Commercial [Member] |  |  |  |
Financing Receivable, Impaired [Line Items] |  |  |  |
Average recorded investment | 3,931 | 3,126 | 3,419 | 2,972
Interest income recognized | 0 | 0 | 0 | 0
Originated Loans [Member] | Commercial Loans [Member] | Commercial Real Estate [Member] |  |  |  |
Financing Receivable, Impaired [Line Items] |  |  |  |
Average recorded investment | 3,243 | 15,278 | 4,584 | 14,264
Interest income recognized | 1 | 0 | 45 | 74
Originated Loans [Member] | Commercial Loans [Member] | Agricultural [Member] |  |  |  |
Financing Receivable, Impaired [Line Items] |  |  |  |
Average recorded investment | 157 | 18 | 165 | 98
Interest income recognized | 1 | 0 | 1 | 1
Originated Loans [Member] | Commercial Loans [Member] | Agricultural Real Estate [Member] |  |  |  |
Financing Receivable, Impaired [Line Items] |  |  |  |
Average recorded investment | 1,549 | 610 | 1,564 | 613
Interest income recognized | 10 | 11 | 21 | 22
Originated Loans [Member] | Commercial Loans [Member] | Business Banking [Member] |  |  |  |
Financing Receivable, Impaired [Line Items] |  |  |  |
Average recorded investment | 890 | 969 | 788 | 973
Interest income recognized | 3 | 6 | 5 | 12
Originated Loans [Member] | Consumer Loans [Member] | Indirect [Member] |  |  |  |
Financing Receivable, Impaired [Line Items] |  |  |  |
Average recorded investment | 25 | 9 | 16 | 10
Interest income recognized | 1 | 0 | 1 | 0
Originated Loans [Member] | Consumer Loans [Member] | Home Equity [Member] |  |  |  |
Financing Receivable, Impaired [Line Items] |  |  |  |
Average recorded investment | 8,205 | 8,223 | 8,310 | 8,093
Interest income recognized | 110 | 120 | 220 | 241
Originated Loans [Member] | Consumer Loans [Member] | Direct [Member] |  |  |  |
Financing Receivable, Impaired [Line Items] |  |  |  |
Average recorded investment | 120 | 0 | 120 | 0
Interest income recognized | 0 | 0 | 0 | 0
Originated Loans [Member] | Residential Real Estate Mortgages [Member] |  |  |  |
Financing Receivable, Impaired [Line Items] |  |  |  |
Average recorded investment | 6,388 | 6,203 | 6,308 | 6,154
Interest income recognized | 68 | 67 | 129 | 134
Acquired Loans [Member] |  |  |  |
Financing Receivable, Impaired [Line Items] |  |  |  |
Average recorded investment | 0 | 1,205 | 172 | 1,205
Interest income recognized | 0 | 0 | 0 | 0
Acquired Loans [Member] | Commercial Loans [Member] | Commercial Real Estate [Member] |  |  |  |
Financing Receivable, Impaired [Line Items] |  |  |  |
Average recorded investment | 0 | 1,205 | 172 | 1,205
Interest income recognized | $ 0 | $ 0 | $ 0 | $ 0

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- Definition Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5258-111524 + Details
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