Allowance for Credit Losses and Credit Quality of Loans, Troubled Debt Restructurings (Details) $ in Thousands	12 Months Ended
Dec. 31, 2020 USD ($) Contract	Dec. 31, 2019 USD ($) Contract
Troubled Debt Restructuring [Abstract]
Number of contracts \| Contract	37	37
Pre-modification outstanding recorded investment	$ 2,900	$ 2,508
Post-modification outstanding recorded investment	$ 3,026	$ 2,603
Number of contracts \| Contract	64	55
Recorded Investment	$ 3,774	$ 2,606
Commercial Loans [Member]
Troubled Debt Restructuring [Abstract]
Number of contracts \| Contract	1	5
Pre-modification outstanding recorded investment	$ 22	$ 892
Post-modification outstanding recorded investment	$ 22	$ 898
Number of contracts \| Contract	2
Recorded Investment	$ 555
Commercial Loans [Member] \| C&I [Member]
Troubled Debt Restructuring [Abstract]
Number of contracts \| Contract	1	1
Pre-modification outstanding recorded investment	$ 22	$ 65
Post-modification outstanding recorded investment	$ 22	$ 65
Number of contracts \| Contract	1
Recorded Investment	$ 387
Commercial Loans [Member] \| CRE [Member]
Troubled Debt Restructuring [Abstract]
Number of contracts \| Contract		1
Pre-modification outstanding recorded investment		$ 402
Post-modification outstanding recorded investment		$ 402
Number of contracts \| Contract	1
Recorded Investment	$ 168
Commercial Loans [Member] \| Business Banking [Member]
Troubled Debt Restructuring [Abstract]
Number of contracts \| Contract		3
Pre-modification outstanding recorded investment		$ 425
Post-modification outstanding recorded investment		$ 431
Consumer Loans [Member]
Troubled Debt Restructuring [Abstract]
Number of contracts \| Contract	1	20
Pre-modification outstanding recorded investment	$ 44	$ 584
Post-modification outstanding recorded investment	$ 44	$ 614
Number of contracts \| Contract	1	32
Recorded Investment	$ 6	$ 1,403
Consumer Loans [Member] \| Auto [Member]
Troubled Debt Restructuring [Abstract]
Number of contracts \| Contract	1
Pre-modification outstanding recorded investment	$ 44
Post-modification outstanding recorded investment	$ 44
Number of contracts \| Contract	1
Recorded Investment	$ 6
Consumer Loans [Member] \| Indirect Auto [Member]
Troubled Debt Restructuring [Abstract]
Number of contracts \| Contract		9
Pre-modification outstanding recorded investment		$ 134
Post-modification outstanding recorded investment		$ 134
Number of contracts \| Contract		3
Recorded Investment		$ 18
Consumer Loans [Member] \| Direct [Member]
Troubled Debt Restructuring [Abstract]
Number of contracts \| Contract		11
Pre-modification outstanding recorded investment		$ 450
Post-modification outstanding recorded investment		$ 480
Number of contracts \| Contract		29
Recorded Investment		$ 1,385
Residential [Member]
Troubled Debt Restructuring [Abstract]
Number of contracts \| Contract	35	12
Pre-modification outstanding recorded investment	$ 2,834	$ 1,032
Post-modification outstanding recorded investment	$ 2,960	$ 1,091
Number of contracts \| Contract	61	23
Recorded Investment	$ 3,213	$ 1,203

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953676-111524

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Number of financing receivable contracts modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953682-111524

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Amount of financing receivable modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953682-111524

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