Loans (Retail Loan Portfolio Categorized by Performance Status) (Details) $ in Thousands	Sep. 30, 2020 USD ($)
Residential Real Estate Loans [Member]
Financing Receivable Recorded Investment [Line Items]
2020	$ 106,889
2019	100,698
2018	94,325
2017	73,933
2016	71,581
Prior	149,476
Revolving Loans Amortized Cost Basis	0
Revolving Loans Converted to Term	0
Total	596,902
Residential Real Estate Loans [Member] \| Performing [Member]
Financing Receivable Recorded Investment [Line Items]
2020	106,889
2019	100,498
2018	93,116
2017	73,143
2016	71,269
Prior	148,682
Revolving Loans Amortized Cost Basis	0
Revolving Loans Converted to Term	0
Total	593,597
Residential Real Estate Loans [Member] \| Non-Performing [Member]
Financing Receivable Recorded Investment [Line Items]
2020	0
2019	200
2018	1,209
2017	790
2016	312
Prior	794
Revolving Loans Amortized Cost Basis	0
Revolving Loans Converted to Term	0
Total	3,305
Residential Real Estate Lines [Member]
Financing Receivable Recorded Investment [Line Items]
2020	0
2019	0
2018	0
2017	0
2016	0
Prior	0
Revolving Loans Amortized Cost Basis	83,792
Revolving Loans Converted to Term	10,225
Total	94,017
Residential Real Estate Lines [Member] \| Performing [Member]
Financing Receivable Recorded Investment [Line Items]
2020	0
2019	0
2018	0
2017	0
2016	0
Prior	0
Revolving Loans Amortized Cost Basis	83,746
Revolving Loans Converted to Term	10,064
Total	93,810
Residential Real Estate Lines [Member] \| Non-Performing [Member]
Financing Receivable Recorded Investment [Line Items]
2020	0
2019	0
2018	0
2017	0
2016	0
Prior	0
Revolving Loans Amortized Cost Basis	46
Revolving Loans Converted to Term	161
Total	207
Consumer Indirect [Member]
Financing Receivable Recorded Investment [Line Items]
2020	223,514
2019	220,856
2018	187,388
2017	128,840
2016	58,038
Prior	21,943
Revolving Loans Amortized Cost Basis	0
Revolving Loans Converted to Term	0
Total	840,579
Consumer Indirect [Member] \| Performing [Member]
Financing Receivable Recorded Investment [Line Items]
2020	223,417
2019	220,615
2018	186,913
2017	128,567
2016	57,873
Prior	21,950
Revolving Loans Amortized Cost Basis	0
Revolving Loans Converted to Term	0
Total	839,335
Consumer Indirect [Member] \| Non-Performing [Member]
Financing Receivable Recorded Investment [Line Items]
2020	97
2019	241
2018	475
2017	273
2016	165
Prior	(7)
Revolving Loans Amortized Cost Basis	0
Revolving Loans Converted to Term	0
Total	1,244
Other Consumer [Member]
Financing Receivable Recorded Investment [Line Items]
2020	5,950
2019	3,684
2018	2,073
2017	1,088
2016	466
Prior	688
Revolving Loans Amortized Cost Basis	2,911
Revolving Loans Converted to Term	0
Total	16,860
Other Consumer [Member] \| Performing [Member]
Financing Receivable Recorded Investment [Line Items]
2020	5,950
2019	3,684
2018	2,073
2017	1,083
2016	466
Prior	688
Revolving Loans Amortized Cost Basis	2,910
Revolving Loans Converted to Term	0
Total	16,854
Other Consumer [Member] \| Non-Performing [Member]
Financing Receivable Recorded Investment [Line Items]
2020	0
2019	0
2018	0
2017	5
2016	0
Prior	0
Revolving Loans Amortized Cost Basis	1
Revolving Loans Converted to Term	0
Total	$ 6

Financing receivable after deferred income offset amount.

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Amount of financing receivable originated four years prior to current fiscal year.

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Amount of financing receivable originated three years prior to current fiscal year.

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Amount of financing receivable originated two years prior to current fiscal year.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of financing receivable that can be withdrawn, repaid and redrawn.

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Amount of revolving financing receivable converted to term loan.

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