Allowance for Loan Losses and Credit Quality of Loans, Troubled Debt Restructured Loans (Details) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018 USD ($) Contract	Jun. 30, 2017 USD ($) Contract	Jun. 30, 2018 USD ($) Contract	Jun. 30, 2017 USD ($) Contract
Troubled Debt Restructured Loans [Abstract]
Number of contracts \| Contract	2	11	17	16
Pre-modification outstanding recorded investment	$ 19	$ 4,213	$ 828	$ 4,522
Post-modification outstanding recorded investment	$ 18	$ 4,147	$ 829	$ 4,469
Number of contracts \| Contract	21	19	40	34
Recorded Investment	$ 1,152	$ 1,183	$ 2,425	$ 2,013
Commercial Loans [Member]
Troubled Debt Restructured Loans [Abstract]
Number of contracts \| Contract	1	2	3	2
Pre-modification outstanding recorded investment	$ 6	$ 3,637	$ 369	$ 3,637
Post-modification outstanding recorded investment	$ 5	$ 3,572	$ 371	$ 3,572
Number of contracts \| Contract	1	1	2	2
Recorded Investment	$ 58	$ 329	$ 258	$ 474
Commercial Loans [Member] \| Commercial [Member]
Troubled Debt Restructured Loans [Abstract]
Number of contracts \| Contract		1		1
Pre-modification outstanding recorded investment		$ 3,300		$ 3,300
Post-modification outstanding recorded investment		$ 3,239		$ 3,239
Number of contracts \| Contract	0		0	1
Recorded Investment	$ 0		$ 0	$ 145
Commercial Loans [Member] \| Business Banking [Member]
Troubled Debt Restructured Loans [Abstract]
Number of contracts \| Contract	1	1	3	1
Pre-modification outstanding recorded investment	$ 6	$ 337	$ 369	$ 337
Post-modification outstanding recorded investment	$ 5	$ 333	$ 371	$ 333
Number of contracts \| Contract	1	1	2	1
Recorded Investment	$ 58	$ 329	$ 258	$ 329
Consumer Loans [Member]
Troubled Debt Restructured Loans [Abstract]
Number of contracts \| Contract	1	5	9	8
Pre-modification outstanding recorded investment	$ 13	$ 230	$ 136	$ 337
Post-modification outstanding recorded investment	$ 13	$ 229	$ 135	$ 343
Number of contracts \| Contract	13	14	25	24
Recorded Investment	$ 495	$ 603	$ 1,260	$ 1,120
Consumer Loans [Member] \| Indirect [Member]
Troubled Debt Restructured Loans [Abstract]
Number of contracts \| Contract		3		3
Pre-modification outstanding recorded investment		$ 32		$ 32
Post-modification outstanding recorded investment		$ 31		$ 31
Number of contracts \| Contract	0	1	0	2
Recorded Investment	$ 0	$ 14	$ 0	$ 19
Consumer Loans [Member] \| Dealer Finance [Member]
Troubled Debt Restructured Loans [Abstract]
Number of contracts \| Contract	1		7
Pre-modification outstanding recorded investment	$ 13		$ 95
Post-modification outstanding recorded investment	$ 13		$ 94
Consumer Loans [Member] \| Home Equity [Member]
Troubled Debt Restructured Loans [Abstract]
Number of contracts \| Contract		1		4
Pre-modification outstanding recorded investment		$ 78		$ 185
Post-modification outstanding recorded investment		$ 78		$ 192
Number of contracts \| Contract	0	13	0	22
Recorded Investment	$ 0	$ 589	$ 0	$ 1,101
Consumer Loans [Member] \| Direct [Member]
Troubled Debt Restructured Loans [Abstract]
Number of contracts \| Contract		1	2	1
Pre-modification outstanding recorded investment		$ 120	$ 41	$ 120
Post-modification outstanding recorded investment		$ 120	$ 41	$ 120
Number of contracts \| Contract	13	0	25	0
Recorded Investment	$ 495	$ 0	$ 1,260	$ 0
Residential Real Estate [Member]
Troubled Debt Restructured Loans [Abstract]
Number of contracts \| Contract		4	5	6
Pre-modification outstanding recorded investment		$ 346	$ 323	$ 548
Post-modification outstanding recorded investment		$ 346	$ 323	$ 554
Number of contracts \| Contract	7	4	13	8
Recorded Investment	$ 599	$ 251	$ 907	$ 419

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Number of financing receivables that have been modified by troubled debt restructurings.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
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