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Loans And Allowance For Credit Losses (Credit Quality Commercial Loan Portfolio Non-Vintage) (Details) - Commercial Portfolio Segment [Member] $ in Thousands | Dec. 31, 2019 USD ($)
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Financing Receivable, Credit Quality Indicator [Line Items] |
Commercial Loan Portfolio Gross Carrying Amount | $ 9,298,380
Pass [Member] |
Financing Receivable, Credit Quality Indicator [Line Items] |
Commercial Loan Portfolio Gross Carrying Amount | 8,910,119
Special Mention [Member] |
Financing Receivable, Credit Quality Indicator [Line Items] |
Commercial Loan Portfolio Gross Carrying Amount | 215,256
Substandard [Member] |
Financing Receivable, Credit Quality Indicator [Line Items] |
Commercial Loan Portfolio Gross Carrying Amount | 164,484
Non-Accrual [Member] |
Financing Receivable, Credit Quality Indicator [Line Items] |
Commercial Loan Portfolio Gross Carrying Amount | 8,521
Business [Member] |
Financing Receivable, Credit Quality Indicator [Line Items] |
Commercial Loan Portfolio Gross Carrying Amount | 5,565,449
Business [Member] | Pass [Member] |
Financing Receivable, Credit Quality Indicator [Line Items] |
Commercial Loan Portfolio Gross Carrying Amount | 5,393,928
Business [Member] | Special Mention [Member] |
Financing Receivable, Credit Quality Indicator [Line Items] |
Commercial Loan Portfolio Gross Carrying Amount | 80,089
Business [Member] | Substandard [Member] |
Financing Receivable, Credit Quality Indicator [Line Items] |
Commercial Loan Portfolio Gross Carrying Amount | 83,943
Business [Member] | Non-Accrual [Member] |
Financing Receivable, Credit Quality Indicator [Line Items] |
Commercial Loan Portfolio Gross Carrying Amount | 7,489
Real Estate - Construction And Land [Member] |
Financing Receivable, Credit Quality Indicator [Line Items] |
Commercial Loan Portfolio Gross Carrying Amount | 899,377
Real Estate - Construction And Land [Member] | Pass [Member] |
Financing Receivable, Credit Quality Indicator [Line Items] |
Commercial Loan Portfolio Gross Carrying Amount | 856,364
Real Estate - Construction And Land [Member] | Special Mention [Member] |
Financing Receivable, Credit Quality Indicator [Line Items] |
Commercial Loan Portfolio Gross Carrying Amount | 42,541
Real Estate - Construction And Land [Member] | Substandard [Member] |
Financing Receivable, Credit Quality Indicator [Line Items] |
Commercial Loan Portfolio Gross Carrying Amount | 470
Real Estate - Construction And Land [Member] | Non-Accrual [Member] |
Financing Receivable, Credit Quality Indicator [Line Items] |
Commercial Loan Portfolio Gross Carrying Amount | 2
Real Estate - Business [Member] |
Financing Receivable, Credit Quality Indicator [Line Items] |
Commercial Loan Portfolio Gross Carrying Amount | 2,833,554
Real Estate - Business [Member] | Pass [Member] |
Financing Receivable, Credit Quality Indicator [Line Items] |
Commercial Loan Portfolio Gross Carrying Amount | 2,659,827
Real Estate - Business [Member] | Special Mention [Member] |
Financing Receivable, Credit Quality Indicator [Line Items] |
Commercial Loan Portfolio Gross Carrying Amount | 92,626
Real Estate - Business [Member] | Substandard [Member] |
Financing Receivable, Credit Quality Indicator [Line Items] |
Commercial Loan Portfolio Gross Carrying Amount | 80,071
Real Estate - Business [Member] | Non-Accrual [Member] |
Financing Receivable, Credit Quality Indicator [Line Items] |
Commercial Loan Portfolio Gross Carrying Amount | $ 1,030

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