Loans And Allowance For Loan Losses (Credit Quality Of Commercial Loan Portfolio) (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Loans And Allowance For Loan Losses [Line Items]
Carrying Amount	$ 6,815,244	$ 6,435,066
Pass [Member]
Loans And Allowance For Loan Losses [Line Items]
Carrying Amount	6,573,388	6,180,979
Special Mention [Member]
Loans And Allowance For Loan Losses [Line Items]
Carrying Amount	98,289	116,692
Substandard [Member]
Loans And Allowance For Loan Losses [Line Items]
Carrying Amount	107,802	95,852
Non-Accrual [Member]
Loans And Allowance For Loan Losses [Line Items]
Carrying Amount	35,765	41,543
Business [Member]
Loans And Allowance For Loan Losses [Line Items]
Carrying Amount	4,095,253	3,715,319
Business [Member] | Pass [Member]
Loans And Allowance For Loan Losses [Line Items]
Carrying Amount	3,993,646	3,618,120
Business [Member] | Special Mention [Member]
Loans And Allowance For Loan Losses [Line Items]
Carrying Amount	52,297	61,916
Business [Member] | Substandard [Member]
Loans And Allowance For Loan Losses [Line Items]
Carrying Amount	38,217	23,691
Business [Member] | Non-Accrual [Member]
Loans And Allowance For Loan Losses [Line Items]
Carrying Amount	11,093	11,592
Real Estate - Construction And Land [Member]
Loans And Allowance For Loan Losses [Line Items]
Carrying Amount	442,093	406,197
Real Estate - Construction And Land [Member] | Pass [Member]
Loans And Allowance For Loan Losses [Line Items]
Carrying Amount	418,424	372,515
Real Estate - Construction And Land [Member] | Special Mention [Member]
Loans And Allowance For Loan Losses [Line Items]
Carrying Amount	1,392	1,697
Real Estate - Construction And Land [Member] | Substandard [Member]
Loans And Allowance For Loan Losses [Line Items]
Carrying Amount	14,079	21,812
Real Estate - Construction And Land [Member] | Non-Accrual [Member]
Loans And Allowance For Loan Losses [Line Items]
Carrying Amount	8,198	10,173
Real Estate - Business [Member]
Loans And Allowance For Loan Losses [Line Items]
Carrying Amount	2,277,898	2,313,550
Real Estate - Business [Member] | Pass [Member]
Loans And Allowance For Loan Losses [Line Items]
Carrying Amount	2,161,318	2,190,344
Real Estate - Business [Member] | Special Mention [Member]
Loans And Allowance For Loan Losses [Line Items]
Carrying Amount	44,600	53,079
Real Estate - Business [Member] | Substandard [Member]
Loans And Allowance For Loan Losses [Line Items]
Carrying Amount	55,506	50,349
Real Estate - Business [Member] | Non-Accrual [Member]
Loans And Allowance For Loan Losses [Line Items]
Carrying Amount	$ 16,474	$ 19,778