Allowance for Loan Losses and Credit Quality of Loans, Troubled Debt Restructurings (Details) $ in Thousands	12 Months Ended
Dec. 31, 2018 USD ($) Contract	Dec. 31, 2017 USD ($) Contract
Troubled Debt Restructured Loans [Abstract]
Number of contracts \| Contract	46	42
Pre-modification outstanding recorded investment	$ 2,285	$ 6,115
Post-modification outstanding recorded investment	$ 2,280	$ 6,116
Number of contracts \| Contract	66	57
Recorded Investment	$ 4,055	$ 3,515
Commercial Loans [Member]
Troubled Debt Restructured Loans [Abstract]
Number of contracts \| Contract	5	4
Pre-modification outstanding recorded investment	$ 581	$ 3,685
Post-modification outstanding recorded investment	$ 581	$ 3,620
Number of contracts \| Contract	3	2
Recorded Investment	$ 338	$ 474
Commercial Loans [Member] \| Commercial [Member]
Troubled Debt Restructured Loans [Abstract]
Number of contracts \| Contract		1
Pre-modification outstanding recorded investment		$ 3,300
Post-modification outstanding recorded investment		$ 3,239
Number of contracts \| Contract	0	1
Recorded Investment	$ 0	$ 145
Commercial Loans [Member] \| Business Banking [Member]
Troubled Debt Restructured Loans [Abstract]
Number of contracts \| Contract	5	3
Pre-modification outstanding recorded investment	$ 581	$ 385
Post-modification outstanding recorded investment	$ 581	$ 381
Number of contracts \| Contract	3	1
Recorded Investment	$ 338	$ 329
Consumer Loans [Member]
Troubled Debt Restructured Loans [Abstract]
Number of contracts \| Contract	27	23
Pre-modification outstanding recorded investment	$ 605	$ 976
Post-modification outstanding recorded investment	$ 601	$ 1,022
Number of contracts \| Contract	37	36
Recorded Investment	$ 1,931	$ 1,739
Consumer Loans [Member] \| Dealer Finance [Member]
Troubled Debt Restructured Loans [Abstract]
Number of contracts \| Contract	17
Pre-modification outstanding recorded investment	$ 204
Post-modification outstanding recorded investment	$ 202
Consumer Loans [Member] \| Direct [Member]
Troubled Debt Restructured Loans [Abstract]
Number of contracts \| Contract	10
Pre-modification outstanding recorded investment	$ 401
Post-modification outstanding recorded investment	$ 399
Number of contracts \| Contract	37
Recorded Investment	$ 1,931
Consumer Loans [Member] \| Indirect [Member]
Troubled Debt Restructured Loans [Abstract]
Number of contracts \| Contract		8
Pre-modification outstanding recorded investment		$ 145
Post-modification outstanding recorded investment		$ 143
Number of contracts \| Contract	0	2
Recorded Investment	$ 0	$ 19
Consumer Loans [Member] \| Home Equity [Member]
Troubled Debt Restructured Loans [Abstract]
Number of contracts \| Contract		13
Pre-modification outstanding recorded investment		$ 552
Post-modification outstanding recorded investment		$ 600
Number of contracts \| Contract	0	34
Recorded Investment	$ 0	$ 1,720
Consumer Loans [Member] \| Direct [Member]
Troubled Debt Restructured Loans [Abstract]
Number of contracts \| Contract		2
Pre-modification outstanding recorded investment		$ 279
Post-modification outstanding recorded investment		$ 279
Number of contracts \| Contract		0
Recorded Investment		$ 0
Residential Real Estate [Member]
Troubled Debt Restructured Loans [Abstract]
Number of contracts \| Contract	14	15
Pre-modification outstanding recorded investment	$ 1,099	$ 1,454
Post-modification outstanding recorded investment	$ 1,098	$ 1,474
Number of contracts \| Contract	26	19
Recorded Investment	$ 1,786	$ 1,302

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-Publisher FASB
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-Topic 310
-SubTopic 10
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