Loans And Allowance For Credit Losses (Summary Classification Of Held To Maturity Loan Portfolio) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2020	Dec. 31, 2019
Loans And Allowance For Loan Losses [Line Items]
Loans and Leases Receivable, Gross	$ 16,420,927	$ 16,420,927	$ 14,737,817
Interest Receivable	41,300	41,300
Commercial Portfolio Segment [Member]
Loans And Allowance For Loan Losses [Line Items]
Accrued Interest Receivable on Held for Investment Loans, Write Off	89	258
Personal Banking Portfolio Segment [Member]
Loans And Allowance For Loan Losses [Line Items]
Accrued Interest Receivable on Held for Investment Loans, Write Off	1,700	4,400
Business [Member]
Loans And Allowance For Loan Losses [Line Items]
Loans and Leases Receivable, Gross	6,683,413	6,683,413	5,565,449
Real Estate - Construction And Land [Member]
Loans And Allowance For Loan Losses [Line Items]
Loans and Leases Receivable, Gross	1,009,729	1,009,729	899,377
Real Estate - Business [Member]
Loans And Allowance For Loan Losses [Line Items]
Loans and Leases Receivable, Gross	2,993,192	2,993,192	2,833,554
Real Estate - Personal [Member]
Loans And Allowance For Loan Losses [Line Items]
Loans and Leases Receivable, Gross	2,753,867	2,753,867	2,354,760
Consumer [Member]
Loans And Allowance For Loan Losses [Line Items]
Loans and Leases Receivable, Gross	2,006,360	2,006,360	1,964,145
Revolving Home Equity [Member]
Loans And Allowance For Loan Losses [Line Items]
Loans and Leases Receivable, Gross	324,203	324,203	349,251
Consumer Credit Card [Member]
Loans And Allowance For Loan Losses [Line Items]
Loans and Leases Receivable, Gross	647,893	647,893	764,977
Overdrafts [Member]
Loans And Allowance For Loan Losses [Line Items]
Loans and Leases Receivable, Gross	$ 2,270	$ 2,270	$ 6,304

Amount of interest receivable on held for investment loans that has been written off.

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- Definition

Loans And Allowance For Loan Losses [Line Items]

+ References

No definition available.

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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=120391452&loc=d3e13212-122682

+ Details

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- Definition

Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=121593590&loc=d3e4428-111522

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