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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Amount of financing receivables related to acquired loans that were individually evaluated for impairment.

+ References

No definition available.

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The threshold balance for classified loans to be individually evaluated for impairment.

+ References

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953550-111524

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- Definition

Amount of allowance for credit losses related to recorded investment.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
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- Definition

Amount of unpaid principal balance of impaired financing receivables with related allowance for credit losses and without related allowance for credit losses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
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- Definition

Amount of investment in impaired financing receivables for which there is no related allowance for credit losses.

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- Definition

Amount of unpaid principal balance of impaired financing receivables for which there is no related allowance for credit losses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount of investment in impaired financing receivables for which there is a related allowance for credit losses.

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Unpaid principal balance of impaired financing receivables for which there is a related allowance for credit losses.

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-Publisher FASB
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