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Allowance for Credit Losses and Credit Quality of Loans, Average Recorded Investments on Loans Specifically Evaluated for Impairment and Interest Income Recognized (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018
Average Recorded Investment and Interest Income Recognized [Abstract] |  |
Average recorded investment | $ 19,733 | $ 20,429
Interest income recognized | 891 | 901
Originated Loans [Member] |  |
Average Recorded Investment and Interest Income Recognized [Abstract] |  |
Average recorded investment | 19,733 | 20,429
Interest income recognized | 891 | 901
Originated Loans [Member] | Commercial Loans [Member] |  |
Average Recorded Investment and Interest Income Recognized [Abstract] |  |
Average recorded investment | 4,642 | 5,549
Interest income recognized | 148 | 155
Originated Loans [Member] | Commercial Loans [Member] | C&I [Member] |  |
Average Recorded Investment and Interest Income Recognized [Abstract] |  |
Average recorded investment | 242 | 453
Interest income recognized | 1 | 1
Originated Loans [Member] | Commercial Loans [Member] | CRE [Member] |  |
Average Recorded Investment and Interest Income Recognized [Abstract] |  |
Average recorded investment | 3,311 | 4,078
Interest income recognized | 123 | 128
Originated Loans [Member] | Commercial Loans [Member] | Business Banking [Member] |  |
Average Recorded Investment and Interest Income Recognized [Abstract] |  |
Average recorded investment | 1,089 | 1,018
Interest income recognized | 24 | 26
Originated Loans [Member] | Consumer Loans [Member] |  |
Average Recorded Investment and Interest Income Recognized [Abstract] |  |
Average recorded investment | 7,586 | 8,101
Interest income recognized | 393 | 441
Originated Loans [Member] | Consumer Loans [Member] | Indirect Auto [Member] |  |
Average Recorded Investment and Interest Income Recognized [Abstract] |  |
Average recorded investment | 192 | 179
Interest income recognized | 10 | 10
Originated Loans [Member] | Consumer Loans [Member] | Direct [Member] |  |
Average Recorded Investment and Interest Income Recognized [Abstract] |  |
Average recorded investment | 7,387 | 7,922
Interest income recognized | 382 | 431
Originated Loans [Member] | Consumer Loans [Member] | Specialty Lending [Member] |  |
Average Recorded Investment and Interest Income Recognized [Abstract] |  |
Average recorded investment | 7 | 0
Interest income recognized | 1 | 0
Originated Loans [Member] | Residential Real Estate [Member] |  |
Average Recorded Investment and Interest Income Recognized [Abstract] |  |
Average recorded investment | 7,505 | 6,779
Interest income recognized | $ 350 | $ 305

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