Allowance for Credit Losses - Impaired Loans (Details) $ in Thousands	12 Months Ended
Dec. 31, 2019 USD ($)
Average Recorded Investment
Impaired loans with no related allowance recorded	$ 15,329
Impaired loans with a related allowance recorded	11,608
Total impaired loans	26,937
Interest Income Recognized
Impaired loans with no related allowance recorded	1,352
Impaired loans with a related allowance recorded	464
Total impaired loans	1,816
Commercial and Industrial
Average Recorded Investment
Impaired loans with no related allowance recorded	3,687
Impaired loans with a related allowance recorded	4,485
Total impaired loans	8,172
Interest Income Recognized
Impaired loans with no related allowance recorded	431
Impaired loans with a related allowance recorded	85
Total impaired loans	516
Commercial real estate
Average Recorded Investment
Impaired loans with no related allowance recorded	2,825
Impaired loans with a related allowance recorded	710
Total impaired loans	3,535
Interest Income Recognized
Impaired loans with no related allowance recorded	481
Impaired loans with a related allowance recorded	40
Total impaired loans	521
Construction
Average Recorded Investment
Impaired loans with no related allowance recorded	8,777
Total impaired loans	15,190
Interest Income Recognized
Impaired loans with no related allowance recorded	440
Total impaired loans	779
Residential Mortgage
Average Recorded Investment
Impaired loans with no related allowance recorded	40
Impaired loans with a related allowance recorded	6,413
Total impaired loans	40
Interest Income Recognized
Impaired loans with a related allowance recorded	$ 339

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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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- References

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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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-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 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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