Allowance for Credit Losses - Amortized Cost Basis of Loans and Leases on Nonaccrual Status (Details) - USD ($)	3 Months Ended
Mar. 31, 2020	Jan. 01, 2020
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual Loans and Leases With No Allowance for Credit Losses	$ 806,000
Nonaccrual Loans and Leases	6,926,000	$ 5,468,000
Interest income on nonaccrual loans	0
Commercial and Industrial
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual Loans and Leases	32,000	32,000
Commercial real estate
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual Loans and Leases		30,000
Construction
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual Loans and Leases	2,422,000
Residential
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual Loans and Leases With No Allowance for Credit Losses	806,000
Nonaccrual Loans and Leases	$ 4,472,000	$ 5,406,000

Amount of financing receivable on nonaccrual status with no allowance for credit loss.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 16
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919258-210447

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount of financing receivable on nonaccrual status.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5111-111524

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 16
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919258-210447

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- Definition

Reflects the amount of additional interest income that would have been recorded if impaired or nonperforming loans were instead current, in compliance with their original terms, and outstanding throughout the reporting period or since origination (if held for part of the period).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=118939409&loc=d3e18794-111554

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