Loans And Related Allowances For Loan Losses (Modification of Troubled Debt Restructuring by Class) (Details) $ in Thousands	12 Months Ended
Dec. 31, 2020 USD ($) contract	Dec. 31, 2019 USD ($) contract
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	10,891
Temporary Rate Modification [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	1	2
Recorded Investment \| $	$ 46	$ 244
Temporary Rate Modification [Member] \| Residential mortgage- term [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	1	2
Recorded Investment \| $	$ 46	$ 244
Extension Of Maturity [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	4	0
Recorded Investment \| $	$ 887
Extension Of Maturity [Member] \| Acquisition and development- All other A&D [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	2
Recorded Investment \| $	$ 430
Extension Of Maturity [Member] \| Residential mortgage- term [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	2
Recorded Investment \| $	$ 457
Modification Of Payment And Other Terms [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	4	2
Recorded Investment \| $	$ 2,582	$ 470
Modification Of Payment And Other Terms [Member] \| Commercial real estate- non owner-occupied [Member]
Financing Receivable, Modifications [Line Items]
Recorded Investment \| $		$ 0
Modification Of Payment And Other Terms [Member] \| Commercial real estate- all other CRE [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	1
Recorded Investment \| $	$ 2,226
Modification Of Payment And Other Terms [Member] \| Acquisition and development- All other A&D [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract		1
Recorded Investment \| $	$ 0	$ 227
Modification Of Payment And Other Terms [Member] \| Residential mortgage- term [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	3	1
Recorded Investment \| $	$ 356	$ 243

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.

No definition available.

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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=121611835&loc=SL6953676-111524

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- Definition

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

+ References

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