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Loans And Related Allowances For Loan Losses (Modification of Troubled Debt Restructuring by Class) (Details) $ in Thousands | 12 Months Ended
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Dec. 31, 2019 USD ($) loan contract | Dec. 31, 2018 USD ($) loan contract
Financing Receivable, Modifications [Line Items] |  |
Number of Contracts | loan | 15 | 16
Recorded Investment | $ 4,200 | $ 4,900
Temporary Rate Modification [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Number of Contracts | contract | 2 |
Recorded Investment | $ 244 |
Temporary Rate Modification [Member] | Residential mortgage- term [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Number of Contracts | contract | 2 |
Recorded Investment | $ 244 |
Extension Of Maturity [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Number of Contracts | contract |  | 2
Recorded Investment |  | $ 566
Extension Of Maturity [Member] | Commercial real estate- all other CRE [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Number of Contracts | contract |  | 1
Recorded Investment |  | $ 179
Extension Of Maturity [Member] | Acquisition and development- 1-4 family residential construction [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Number of Contracts | contract |  | 1
Recorded Investment |  | $ 387
Modification Of Payment And Other Terms [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Number of Contracts | contract | 2 | 4
Recorded Investment | $ 470 | $ 793
Modification Of Payment And Other Terms [Member] | Commercial real estate- non owner-occupied [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Number of Contracts | contract |  | 3
Recorded Investment |  | $ 358
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 | $ 227 |
Modification Of Payment And Other Terms [Member] | Residential mortgage- term [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Number of Contracts | contract | 1 | 1
Recorded Investment | $ 243 | $ 435

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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 + Details
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