Loans and Allowance for Credit Losses on Loans - Allowance for credit losses and recorded investment in loans by loan classification and by impairment method (Details) $ in Thousands	Dec. 31, 2019 USD ($)
Unpaid Principal Balance
Total with no related allowance recorded	$ 7,567
Total with an allowance recorded	2,697
Total	10,264
Recorded Investment
Total with no related allowance recorded	7,567
Total with an allowance recorded	2,697
Total	10,264
Total with an allowance recorded, Allowance for Loan Losses Allocated	1,835
Commercial
Unpaid Principal Balance
Total with no related allowance recorded	2,113
Total with an allowance recorded	2,697
Recorded Investment
Total with no related allowance recorded	2,113
Total with an allowance recorded	2,697
Total with an allowance recorded, Allowance for Loan Losses Allocated	1,835
Home equity
Unpaid Principal Balance
Total with no related allowance recorded	360
Recorded Investment
Total with no related allowance recorded	360
CRE
Unpaid Principal Balance
Total with no related allowance recorded	5,094
Recorded Investment
Total with no related allowance recorded	$ 5,094

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

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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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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+ 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
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-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5212-111524

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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=121611835&loc=d3e5212-111524

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+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 15
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