Loans - Impaired Financing Receivables with Related and not Related Allowances (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
With no related allowance recorded:
Average Recorded Investment, Total		$ 25,825
Interest Income Recognized, Total		259
Cash Basis Interest Recognized, Total		259
Commercial Industrial And Agricultural [Member]
With an allowance recorded:
Average Recorded Investment		4,272
Interest Income Recognized		17
Cash Basis Interest Recognized	$ 17
With no related allowance recorded:
Average Recorded Investment		7,161
Interest Income Recognized		42
Cash Basis Interest Recognized		42
Commercial Mortgages
With an allowance recorded:
Average Recorded Investment		4,331
Interest Income Recognized		37
Cash Basis Interest Recognized	37
With no related allowance recorded:
Average Recorded Investment		9,598
Interest Income Recognized		158
Cash Basis Interest Recognized		158
Residential Real Estate [Member]
With an allowance recorded:
Average Recorded Investment		463
Interest Income Recognized		5
Cash Basis Interest Recognized	$ 5
With no related allowance recorded:
Average Recorded Investment		0
Interest Income Recognized		0
Cash Basis Interest Recognized		$ 0

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=121611835&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=121611835&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.

+ References

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- Definition

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=121611835&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=121611835&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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