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Allowance for Loan Losses and Credit Quality of Loans, Impaired Loans (Details) - USD ($) $ in Thousands | Mar. 31, 2019 | Dec. 31, 2018
--- | --- | ---
Allowance for Loan Losses and Credit Quality of Loans [Abstract] |  |
Threshold balance for classified loans to be evaluated individually for impairment | $ 750 |
Total Loans [Abstract] |  |
Recorded investment balance (book) | 21,042 | $ 20,578
Unpaid principal balance (legal) | 29,250 | 28,552
Related allowance | 25 | 25
Acquired impaired loans specifically evaluated for impairment | 0 | 0
Originated Loans [Member] |  |
With an allowance recorded [Abstract] |  |
Recorded investment balance (book) | 20,813 | 20,345
Unpaid principal balance (legal) | 29,014 | 28,314
Originated Loans [Member] | Commercial Loans [Member] |  |
With no related allowance recorded [Abstract] |  |
Recorded investment balance (book) | 5,780 | 5,553
Unpaid principal balance (legal) | 9,129 | 8,828
With an allowance recorded [Abstract] |  |
Recorded investment balance (book) | 229 | 233
Unpaid principal balance (legal) | 236 | 238
Total Loans [Abstract] |  |
Related allowance | 25 | 25
Originated Loans [Member] | Commercial Loans [Member] | C&I [Member] |  |
With no related allowance recorded [Abstract] |  |
Recorded investment balance (book) | 244 | 228
Unpaid principal balance (legal) | 516 | 497
With an allowance recorded [Abstract] |  |
Recorded investment balance (book) | 229 | 233
Unpaid principal balance (legal) | 236 | 238
Total Loans [Abstract] |  |
Related allowance | 25 | 25
Originated Loans [Member] | Commercial Loans [Member] | CRE [Member] |  |
With no related allowance recorded [Abstract] |  |
Recorded investment balance (book) | 4,237 | 4,312
Unpaid principal balance (legal) | 6,272 | 6,330
Originated Loans [Member] | Commercial Loans [Member] | Business Banking [Member] |  |
With no related allowance recorded [Abstract] |  |
Recorded investment balance (book) | 1,299 | 1,013
Unpaid principal balance (legal) | 2,341 | 2,001
Originated Loans [Member] | Consumer Loans [Member] |  |
With no related allowance recorded [Abstract] |  |
Recorded investment balance (book) | 7,813 | 7,887
Unpaid principal balance (legal) | 10,046 | 10,072
Originated Loans [Member] | Consumer Loans [Member] | Dealer Finance [Member] |  |
With no related allowance recorded [Abstract] |  |
Recorded investment balance (book) | 187 | 143
Unpaid principal balance (legal) | 283 | 241
Originated Loans [Member] | Consumer Loans [Member] | Direct [Member] |  |
With no related allowance recorded [Abstract] |  |
Recorded investment balance (book) | 7,626 | 7,744
Unpaid principal balance (legal) | 9,763 | 9,831
Originated Loans [Member] | Residential Real Estate [Member] |  |
With an allowance recorded [Abstract] |  |
Recorded investment balance (book) | 7,220 | 6,905
Unpaid principal balance (legal) | $ 9,839 | $ 9,414

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