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Allowance for Loan Losses and Credit Quality of Loans, Impaired Loans (Details) - USD ($) $ in Thousands | Sep. 30, 2019 | Jun. 30, 2019 | Dec. 31, 2018
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Allowance for Loan Losses and Credit Quality of Loans [Abstract] |  |  |
Threshold balance for classified loans to be evaluated individually for impairment | $ 1,000 | $ 750 |
Total Loans [Abstract] |  |  |
Recorded investment balance (book) | 18,057 |  | $ 20,578
Unpaid principal balance (legal) | 22,125 |  | 28,552
Related allowance | 0 |  | 25
Acquired impaired loans specifically evaluated for impairment | 0 |  | 0
Originated Loans [Member] |  |  |
With no related allowance recorded [Abstract] |  |  |
Recorded investment balance (book) | 18,057 |  | 20,345
Unpaid principal balance (legal) | 22,125 |  | 28,314
Originated Loans [Member] | Commercial Loans [Member] |  |  |
With no related allowance recorded [Abstract] |  |  |
Recorded investment balance (book) | 3,117 |  | 5,553
Unpaid principal balance (legal) | 3,762 |  | 8,828
With an allowance recorded [Abstract] |  |  |
Recorded investment balance (book) | 0 |  | 233
Unpaid principal balance (legal) | 0 |  | 238
Total Loans [Abstract] |  |  |
Related allowance | 0 |  | 25
Originated Loans [Member] | Commercial Loans [Member] | C&I [Member] |  |  |
With no related allowance recorded [Abstract] |  |  |
Recorded investment balance (book) | 78 |  | 228
Unpaid principal balance (legal) | 304 |  | 497
With an allowance recorded [Abstract] |  |  |
Recorded investment balance (book) | 0 |  | 233
Unpaid principal balance (legal) | 0 |  | 238
Total Loans [Abstract] |  |  |
Related allowance | 0 |  | 25
Originated Loans [Member] | Commercial Loans [Member] | CRE [Member] |  |  |
With no related allowance recorded [Abstract] |  |  |
Recorded investment balance (book) | 2,046 |  | 4,312
Unpaid principal balance (legal) | 2,046 |  | 6,330
Originated Loans [Member] | Commercial Loans [Member] | Business Banking [Member] |  |  |
With no related allowance recorded [Abstract] |  |  |
Recorded investment balance (book) | 993 |  | 1,013
Unpaid principal balance (legal) | 1,412 |  | 2,001
Originated Loans [Member] | Consumer Loans [Member] |  |  |
With no related allowance recorded [Abstract] |  |  |
Recorded investment balance (book) | 7,267 |  | 7,887
Unpaid principal balance (legal) | 8,743 |  | 10,072
Originated Loans [Member] | Consumer Loans [Member] | Dealer Finance [Member] |  |  |
With no related allowance recorded [Abstract] |  |  |
Recorded investment balance (book) | 194 |  | 143
Unpaid principal balance (legal) | 279 |  | 241
Originated Loans [Member] | Consumer Loans [Member] | Direct [Member] |  |  |
With no related allowance recorded [Abstract] |  |  |
Recorded investment balance (book) | 7,073 |  | 7,744
Unpaid principal balance (legal) | 8,464 |  | 9,831
Originated Loans [Member] | Residential Real Estate [Member] |  |  |
With no related allowance recorded [Abstract] |  |  |
Recorded investment balance (book) | 7,673 |  | 6,905
Unpaid principal balance (legal) | $ 9,620 |  | $ 9,414

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