Loans (Narrative) (Details)	3 Months Ended	12 Months Ended
Mar. 31, 2020 USD ($) item contract loan	Mar. 31, 2019 contract loan	Dec. 31, 2019 USD ($) loan item
Financing Receivable, Past Due [Line Items]
Allowance for loan losses, TDR	$ 0		$ 14,000
Number of days past due to be considered default	90 days
Minimum prior year principal balance of commercial Real estate loans required to be reviewed annually			80.00%
Number of contracts with payment default \| contract	0	0
Number of commitments to lend \| item	0		0
Number of loans in the process of foreclosure \| loan	0		0
Number of loans modified \| loan	0	0
Accrued interest receivable	$ 8,656,000		$ 8,409,000
Residential Mortgages [Member]
Financing Receivable, Past Due [Line Items]
Real estate acquired through foreclosure	$ 0		$ 0

Allowance for Loan and Lease Losses, Trouble Debt Restructuring

No definition available.

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- Definition

Loans And Leases Receivable, Number Of Commitments To Lend

+ References

No definition available.

+ Details

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- Definition

Represents the minimum prior year principal balance of commercial real estate loans that is required to be reviewed annually.

+ References

No definition available.

+ Details

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- Definition

The number of days that a loan is past due to be considered in default under the modified terms of TDR.

+ References

No definition available.

+ Details

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- Definition

Number of Loans In Process Of Foreclosure

+ References

No definition available.

+ Details

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- Definition

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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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953682-111524

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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.

+ Details

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- Definition

Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.8)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Carrying amount as of the balance sheet date of land and buildings obtained through foreclosure proceedings or defeasance in full or partial satisfaction of a debt arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5162-111524

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=118952595&loc=d3e4437-111522

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Period Type:	instant

- Details

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