Loans - Impaired Financing Receivables with Related and not Related Allowances (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2020
With no related allowance recorded:
Average Recorded Investment, Total	$ 29,008	$ 26,851
Interest Income Recognized, Total	149	408
Cash Basis Interest Recognized, Total	149	408
Commercial, industrial and agricultural
With an allowance recorded:
Average Recorded Investment	2,052	3,532
Interest Income Recognized	28	45
Cash Basis Interest Recognized	28	45
With no related allowance recorded:
Average Recorded Investment	7,367	7,196
Interest Income Recognized	49	91
Cash Basis Interest Recognized	49	91
Commercial mortgages
With an allowance recorded:
Average Recorded Investment	4,330	4,330
Interest Income Recognized	4	41
Cash Basis Interest Recognized	4	41
With no related allowance recorded:
Average Recorded Investment	14,684	11,293
Interest Income Recognized	66	224
Cash Basis Interest Recognized	66	224
Residential real estate
With an allowance recorded:
Average Recorded Investment	461	462
Interest Income Recognized	0	5
Cash Basis Interest Recognized	0	5
With no related allowance recorded:
Average Recorded Investment	114	38
Interest Income Recognized	2	2
Cash Basis Interest Recognized	$ 2	$ 2

Impaired Financing Receivable, Average Recorded Investment With An Allowance Recorded [Abstract]

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- Definition

Impaired Financing Receivable, Average Recorded Investment With No Allowance Recorded [Abstract]

+ References

No definition available.

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- Definition

Average 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 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=123577603&loc=d3e5212-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=123577603&loc=d3e5258-111524

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- Definition

Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

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Amount of interest income recognized on a cash-basis method of accounting that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

+ References

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Amount of average investment 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 17
-URI http://asc.fasb.org/extlink&oid=123577603&loc=d3e5258-111524

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=123577603&loc=d3e5212-111524

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Amount of interest income, recognized on accrual basis, on financing receivables that are recognized as impaired, for which there is no related allowance for credit losses.

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Amount of interest income, recognized on cash basis, on financing receivables, for which there is no related allowance for credit losses and are recognized as impaired.

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Amount of interest income, recognized on accrual basis, on financing receivables, for which there is a related allowance for credit losses and are recognized as impaired.

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Amount of interest income on financing receivables, for which there is a related allowance for credit losses, recognized on a cash-basis method of accounting that the financing receivables were impaired.

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