Loans and Allowance for Loan and Lease Losses (Narrative) (Details)	3 Months Ended	12 Months Ended
Mar. 31, 2020 USD ($) Loan Borrower	Dec. 31, 2019 USD ($) Loan
Financing Receivable, Allowance for Credit Losses [Line Items]
Financing receivable deferred fees and costs	$ 1,019,000	$ 1,081,000
Financing receivable, modifications, recorded investment	$ 981,000	$ 2,238,000
Number of troubled debt restructured loans \| Loan	0	0
Number of borrowers \| Borrower	482
Aggregate loans outstanding	$ 220,576,000
Eight Loans with Five Relationships [Member] \| Nonaccruing [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Financing receivable, modifications, recorded investment		$ 1,748,000
One Large Relationships [Member] \| Nonaccruing [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Financing receivable, modifications, recorded investment		1,252,000
Residential Mortgage [Member] \| Residential Portfolio [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Financing receivable, modifications, recorded investment	495,000	490,000
Residential Mortgage [Member] \| Residential Portfolio [Member] \| Four Unrelated Borrowers [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Financing receivable, modifications, recorded investment	495,000
Residential Mortgage [Member] \| Residential Portfolio [Member] \| Three Unrelated Borrowers [Member] \| Accruing
Financing Receivable, Allowance for Credit Losses [Line Items]
Financing receivable, modifications, recorded investment		$ 490,000
Commercial Real Estate [Member] \| Residential Mortgage [Member] \| Residential Portfolio [Member] \| Four Unrelated Borrowers [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Financing receivable, modifications, recorded investment	440,000
Commercial Real Estate - Construction [Member] \| Residential Mortgage [Member] \| Residential Portfolio [Member] \| Four Unrelated Borrowers [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Financing receivable, modifications, recorded investment	39,000
Commercial and Industrial [Member] \| Residential Mortgage [Member] \| Residential Portfolio [Member] \| Four Unrelated Borrowers [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Financing receivable, modifications, recorded investment	$ 7,000

Financing receivable deferred fees and costs.

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- Definition

Number of borrowers.

+ References

No definition available.

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- Definition

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+ References

No definition available.

+ Details

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- Definition

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

+ References

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- Definition

Amount of financing receivable modified as troubled debt restructuring.

+ 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

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=118939409&loc=d3e18845-111554

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- Definition

This is the sum of principal amount outstanding for both securitized and unsecuritized loans of all types.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118948506&loc=d3e107314-111719

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