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Loans And Allowance For Credit Losses (Outstanding Balance Of Loans Classified As Troubled Debt Restructurings) (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Loans And Allowance For Loan Losses [Line Items] |  |
Restructured loans | $ 140,627 | $ 79,450
Balance 90 days past due at any time during previous 12 months | 1,869 |
Commercial Portfolio Segment [Member] | Business [Member] |  |
Loans And Allowance For Loan Losses [Line Items] |  |
Restructured loans | 71,088 |
Balance 90 days past due at any time during previous 12 months | 664 |
Commercial Portfolio Segment [Member] | Real Estate - Construction And Land [Member] |  |
Loans And Allowance For Loan Losses [Line Items] |  |
Restructured loans | 40 |
Balance 90 days past due at any time during previous 12 months | 0 |
Commercial Portfolio Segment [Member] | Real Estate - Business [Member] |  |
Loans And Allowance For Loan Losses [Line Items] |  |
Restructured loans | 55,306 |
Balance 90 days past due at any time during previous 12 months | 0 |
Personal Banking Portfolio Segment [Member] | Real Estate - Personal [Member] |  |
Loans And Allowance For Loan Losses [Line Items] |  |
Restructured loans | 3,222 |
Balance 90 days past due at any time during previous 12 months | 242 |
Personal Banking Portfolio Segment [Member] | Consumer [Member] |  |
Loans And Allowance For Loan Losses [Line Items] |  |
Restructured loans | 3,365 |
Balance 90 days past due at any time during previous 12 months | 242 |
Personal Banking Portfolio Segment [Member] | Revolving Home Equity [Member] |  |
Loans And Allowance For Loan Losses [Line Items] |  |
Restructured loans | 28 |
Balance 90 days past due at any time during previous 12 months | 0 |
Personal Banking Portfolio Segment [Member] | Consumer Credit Card [Member] |  |
Loans And Allowance For Loan Losses [Line Items] |  |
Restructured loans | 7,578 |
Balance 90 days past due at any time during previous 12 months | $ 721 |

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- Definition Loans And Allowance For Loan Losses [Line Items] + References No definition available. + Details
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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=121611835&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=121585226&loc=d3e18845-111554 + Details
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