Loans And Allowance For Loan Losses (Aging Information On Past Due And Accruing Loans) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Loans And Allowance For Loan Losses [Line Items]
Financing Receivable, Recorded Investment, 1 to 29 Days Past Due	$ 11,625,519	$ 11,365,009
30 - 89 Days Past Due	48,442	49,796
90 Days Past Due and Still Accruing	12,181	13,658
Non-accrual	35,818	40,775
Total	11,721,960	11,469,238
Business [Member] \| Commercial Portfolio Segment [Member]
Loans And Allowance For Loan Losses [Line Items]
Financing Receivable, Recorded Investment, 1 to 29 Days Past Due	4,167,679	3,946,144
30 - 89 Days Past Due	5,893	11,152
90 Days Past Due and Still Accruing	444	1,096
Non-accrual	9,961	11,560
Total	4,183,977	3,969,952
Real Estate - Construction And Land [Member] \| Commercial Portfolio Segment [Member]
Loans And Allowance For Loan Losses [Line Items]
Financing Receivable, Recorded Investment, 1 to 29 Days Past Due	413,150	397,488
30 - 89 Days Past Due	6,032	827
90 Days Past Due and Still Accruing	258	35
Non-accrual	4,488	5,157
Total	423,928	403,507
Real Estate - Business [Member] \| Commercial Portfolio Segment [Member]
Loans And Allowance For Loan Losses [Line Items]
Financing Receivable, Recorded Investment, 1 to 29 Days Past Due	2,261,667	2,266,688
30 - 89 Days Past Due	6,293	3,661
90 Days Past Due and Still Accruing	0	0
Non-accrual	15,028	17,866
Total	2,282,988	2,288,215
Real Estate - Personal [Member] \| Personal Banking Portfolio Segment [Member]
Loans And Allowance For Loan Losses [Line Items]
Financing Receivable, Recorded Investment, 1 to 29 Days Past Due	1,874,779	1,868,606
30 - 89 Days Past Due	5,092	6,618
90 Days Past Due and Still Accruing	1,345	1,676
Non-accrual	6,341	6,192
Total	1,887,557	1,883,092
Consumer [Member] \| Personal Banking Portfolio Segment [Member]
Loans And Allowance For Loan Losses [Line Items]
Financing Receivable, Recorded Investment, 1 to 29 Days Past Due	1,750,328	1,687,285
30 - 89 Days Past Due	14,965	16,053
90 Days Past Due and Still Accruing	1,595	1,796
Non-accrual	0	0
Total	1,766,888	1,705,134
Revolving Home Equity [Member] \| Personal Banking Portfolio Segment [Member]
Loans And Allowance For Loan Losses [Line Items]
Financing Receivable, Recorded Investment, 1 to 29 Days Past Due	423,984	428,478
30 - 89 Days Past Due	2,241	1,552
90 Days Past Due and Still Accruing	739	843
Non-accrual	0	0
Total	426,964	430,873
Consumer Credit Card [Member] \| Personal Banking Portfolio Segment [Member]
Loans And Allowance For Loan Losses [Line Items]
Financing Receivable, Recorded Investment, 1 to 29 Days Past Due	724,023	764,599
30 - 89 Days Past Due	7,720	9,559
90 Days Past Due and Still Accruing	7,800	8,212
Non-accrual	0	0
Total	739,543	782,370
Overdrafts [Member] \| Personal Banking Portfolio Segment [Member]
Loans And Allowance For Loan Losses [Line Items]
Financing Receivable, Recorded Investment, 1 to 29 Days Past Due	9,909	5,721
30 - 89 Days Past Due	206	374
90 Days Past Due and Still Accruing	0	0
Non-accrual	0	0
Total	$ 10,115	$ 6,095

Financing Receivable, Recorded Investment, Thirty to Eighty-Nine Days Past Due

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Financing receivables that are less than 30 days past due.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

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Recorded investment in financing receivables that are 90 days or more past due and still accruing.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

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Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date.

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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

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