Loans - Restructured in Troubled Debt (Details) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020 USD ($) loan	Sep. 30, 2019 USD ($) loan	Sep. 30, 2020 USD ($) loan	Sep. 30, 2019 USD ($) loan	Dec. 31, 2019 USD ($) loan
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans \| loan	32		32		23
Loan Balance	$ 10,970		$ 10,970		$ 9,802
Specific Reserve	$ 806		$ 806		$ 358
Number of loans, period of time \| loan	1	1	10	1
Trouble Debt Restructuring
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of loans, period of time \| loan	1	1	10	1
Pre-Modification Outstanding Recorded Investment Balance	$ 46	$ 383	$ 1,755	$ 383
Post-Modification Outstanding Recorded Investment Reserve	$ 46	$ 383	$ 1,755	$ 383
Commercial, industrial and agricultural
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans \| loan	17		17		10
Loan Balance	$ 4,379		$ 4,379		$ 3,093
Specific Reserve	$ 497		$ 497		$ 28
Commercial, industrial and agricultural \| Trouble Debt Restructuring
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of loans, period of time \| loan	0	0	8	0
Pre-Modification Outstanding Recorded Investment Balance	$ 0	$ 0	$ 1,593	$ 0
Post-Modification Outstanding Recorded Investment Reserve	$ 0	$ 0	$ 1,593	$ 0
Commercial mortgages
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans \| loan	14		14		13
Loan Balance	$ 6,482		$ 6,482		$ 6,709
Specific Reserve	$ 309		$ 309		$ 330
Commercial mortgages \| Trouble Debt Restructuring
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of loans, period of time \| loan	1	1	1	1
Pre-Modification Outstanding Recorded Investment Balance	$ 46	$ 383	$ 46	$ 383
Post-Modification Outstanding Recorded Investment Reserve	$ 46	$ 383	$ 46	$ 383
Residential real estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans \| loan	1		1		0
Loan Balance	$ 109		$ 109		$ 0
Specific Reserve	$ 0		$ 0		$ 0
Residential real estate \| Trouble Debt Restructuring
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of loans, period of time \| loan	0	0	1	0
Pre-Modification Outstanding Recorded Investment Balance	$ 0	$ 0	$ 116	$ 0
Post-Modification Outstanding Recorded Investment Reserve	$ 0	$ 0	$ 116	$ 0
Consumer
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans \| loan	0		0		0
Loan Balance	$ 0		$ 0		$ 0
Specific Reserve	$ 0		$ 0		$ 0
Consumer \| Trouble Debt Restructuring
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of loans, period of time \| loan	0	0	0	0
Pre-Modification Outstanding Recorded Investment Balance	$ 0	$ 0	$ 0	$ 0
Post-Modification Outstanding Recorded Investment Reserve	$ 0	$ 0	$ 0	$ 0
Credit cards
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans \| loan	0		0		0
Loan Balance	$ 0		$ 0		$ 0
Specific Reserve	$ 0		$ 0		$ 0
Credit cards \| Trouble Debt Restructuring
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of loans, period of time \| loan	0	0	0	0
Pre-Modification Outstanding Recorded Investment Balance	$ 0	$ 0	$ 0	$ 0
Post-Modification Outstanding Recorded Investment Reserve	$ 0	$ 0	$ 0	$ 0

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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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-SubTopic 40
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