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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
--- | ---
Mar. 31, 2019 | Mar. 31, 2018
Average Recorded Investment and Interest Income Recognized [Abstract] |  |
Average recorded investment | $ 21,062 | $ 21,182
Interest income recognized | 214 | 222
Originated Loans [Member] |  |
Average Recorded Investment and Interest Income Recognized [Abstract] |  |
Average recorded investment | 21,062 | 21,182
Interest income recognized | 214 | 222
Originated Loans [Member] | Commercial Loans [Member] |  |
Average Recorded Investment and Interest Income Recognized [Abstract] |  |
Average recorded investment | 6,007 | 5,927
Interest income recognized | 37 | 37
Originated Loans [Member] | Commercial Loans [Member] | C&I [Member] |  |
Average Recorded Investment and Interest Income Recognized [Abstract] |  |
Average recorded investment | 462 | 467
Interest income recognized | 1 | 0
Originated Loans [Member] | Commercial Loans [Member] | CRE [Member] |  |
Average Recorded Investment and Interest Income Recognized [Abstract] |  |
Average recorded investment | 4,282 | 4,506
Interest income recognized | 30 | 32
Originated Loans [Member] | Commercial Loans [Member] | Business Banking [Member] |  |
Average Recorded Investment and Interest Income Recognized [Abstract] |  |
Average recorded investment | 1,263 | 954
Interest income recognized | 6 | 5
Originated Loans [Member] | Consumer Loans [Member] |  |
Average Recorded Investment and Interest Income Recognized [Abstract] |  |
Average recorded investment | 7,889 | 8,374
Interest income recognized | 100 | 112
Originated Loans [Member] | Consumer Loans [Member] | Dealer Finance [Member] |  |
Average Recorded Investment and Interest Income Recognized [Abstract] |  |
Average recorded investment | 173 | 184
Interest income recognized | 2 | 3
Originated Loans [Member] | Consumer Loans [Member] | Direct [Member] |  |
Average Recorded Investment and Interest Income Recognized [Abstract] |  |
Average recorded investment | 7,716 | 8,190
Interest income recognized | 98 | 109
Originated Loans [Member] | Residential Real Estate [Member] |  |
Average Recorded Investment and Interest Income Recognized [Abstract] |  |
Average recorded investment | 7,166 | 6,881
Interest income recognized | $ 77 | $ 73

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