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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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- References

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- Definition

Average 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 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5258-111524

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Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

+ 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
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524

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