Loans - Loans Individually Evaluated for Impairment Including Loans Modified in Troubled Debt Restructurings by Portfolio Segment (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
With an allowance recorded:
Allowance for Loan Losses Allocated	$ 5,154	$ 2,301
With no related allowance recorded:
Unpaid Principal Balance, Total	33,579	24,431
Recorded Investment, Total	30,892	20,755
Commercial, industrial and agricultural
With an allowance recorded:
Unpaid Principal Balance	7,111	2,657
Recorded Investment	7,068	1,476
Allowance for Loan Losses Allocated	3,523	673
With no related allowance recorded:
Unpaid Principal Balance	4,780	9,845
Recorded Investment	4,627	9,695
Commercial mortgages
With an allowance recorded:
Unpaid Principal Balance	6,542	6,541
Recorded Investment	4,312	4,349
Allowance for Loan Losses Allocated	1,580	1,594
With no related allowance recorded:
Unpaid Principal Balance	14,666	4,903
Recorded Investment	14,425	4,770
Residential Real Estate
With an allowance recorded:
Unpaid Principal Balance	480	485
Recorded Investment	460	465
Allowance for Loan Losses Allocated	51	34
With no related allowance recorded:
Unpaid Principal Balance	0	0
Recorded Investment	$ 0	$ 0

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

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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=118936363&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=118936363&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.

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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=118936363&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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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=118936363&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=118936363&loc=d3e5212-111524

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