Loans - Loans Individually Evaluated for Impairment Including Loans Modified in Troubled Debt Restructurings by Portfolio Segment (Details) $ in Thousands	Dec. 31, 2019 USD ($)
With an allowance recorded:
Allowance for Loan Losses Allocated	$ 2,301
With no related allowance recorded:
Unpaid Principal Balance, Total	24,431
Recorded Investment, Total	20,755
Commercial, industrial, and agricultural
With an allowance recorded:
Unpaid Principal Balance	2,657
Recorded Investment	1,476
Allowance for Loan Losses Allocated	673
With no related allowance recorded:
Unpaid Principal Balance	9,845
Recorded Investment	9,695
Commercial mortgages
With an allowance recorded:
Unpaid Principal Balance	6,541
Recorded Investment	4,349
Allowance for Loan Losses Allocated	1,594
With no related allowance recorded:
Unpaid Principal Balance	4,903
Recorded Investment	4,770
Residential Real Estate
With an allowance recorded:
Unpaid Principal Balance	485
Recorded Investment	465
Allowance for Loan Losses Allocated	34
With no related allowance recorded:
Unpaid Principal Balance	0
Recorded Investment	$ 0

Impaired Financing Receivable, Unpaid Principal Balance With No Allowance Recorded [Abstract]

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- Definition

Impaired Financing Receivable, Unpaid Principal Balance With an Allowance Recorded [Abstract]

+ References

No definition available.

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- Definition

Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953550-111524

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- Definition

Amount of allowance for credit losses related to recorded investment.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5212-111524

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Amount of unpaid principal balance of impaired financing receivables with related allowance for credit losses and without related allowance for credit losses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (a)(4)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5212-111524

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Amount of investment in impaired financing receivables for which there is no related allowance for credit losses.

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- Definition

Amount of unpaid principal balance of impaired financing receivables for which there is no related allowance for credit losses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (a)(4)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5212-111524

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Amount of investment in impaired financing receivables for which there is a related allowance for credit losses.

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- Definition

Unpaid principal balance of impaired financing receivables for which there is a related allowance for credit losses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (a)(4)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5212-111524

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