Allowance for Loan Losses (the Allowance) - Loan and lease modifications granted categorized as TDRs (Details) $ in Thousands	12 Months Ended
Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($) contract
Loan and lease modifications
Number of Contracts \| contract		5
Pre-Modification Outstanding Recorded Investment		$ 2,973
Post-Modification Outstanding Recorded Investment		2,973
Related Allowance		63
Loan and lease modifications granted and subsequently defaulted	$ 0	$ 0
Commercial mortgage
Loan and lease modifications
Number of Contracts \| contract		1
Pre-Modification Outstanding Recorded Investment		$ 796
Post-Modification Outstanding Recorded Investment		$ 796
Land and Construction
Loan and lease modifications
Number of Contracts \| contract		1
Pre-Modification Outstanding Recorded Investment		$ 1,628
Post-Modification Outstanding Recorded Investment		$ 1,628
Commercial and industrial
Loan and lease modifications
Number of Contracts \| contract		2
Pre-Modification Outstanding Recorded Investment		$ 282
Post-Modification Outstanding Recorded Investment		282
Related Allowance		$ 63
Small Business Loans
Loan and lease modifications
Number of Contracts \| contract		1
Pre-Modification Outstanding Recorded Investment		$ 267
Post-Modification Outstanding Recorded Investment		$ 267

Amount of credit loss expense (reversal of expense) for financing receivable from change in methodology.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 11
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919244-210447

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+ References

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Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953676-111524

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Amount, after troubled debt restructuring, of modified financing receivable.

+ References

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Amount, before troubled debt restructuring, of financing receivable to be modified.

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Amount of financing receivable modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953682-111524

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