Loans And Allowance For Credit Losses (Summary Of Major Portfolio Segment And Specific Loan Class) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for sale	$ 171,328	$ 251,651
Commercial and industrial	12,481,083	11,256,945
Leasing	387,929	422,513
Owner occupied	7,437,195	7,589,082
Municipal	449,418	494,183
Total commercial	20,755,625	19,762,723
Construction and land development	2,182,821	1,939,413
Term	8,005,837	8,062,819
Loans receivable, gross, commercial, real estate	10,188,658	10,002,232
Home equity credit line	2,133,120	2,177,680
1-4 family residential	4,736,665	4,350,329
Construction and other consumer real estate	324,922	321,235
Bankcard and other revolving plans	356,240	306,428
Other	197,864	216,379
Total consumer	7,748,811	7,372,051
FDIC-supported loans	350,271	528,241
Total loans	$ 39,043,365	$ 37,665,247

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Amount before allowance of commercial leases and leveraged lease transactions where the entity is long-term creditor. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes leases covered under loss sharing agreements.