Loans (Schedule Of Loans By Portfolio Segment) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013		Dec. 31, 2012		Mar. 31, 2012		Dec. 31, 2011
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	$ 15,889,670		$ 16,708,582		$ 15,971,330
Allowance for loan losses	265,218		276,963		346,016		384,351
Total net loans	15,624,452		16,431,619		15,625,314
Commercial Financial And Industrial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	8,091,186				7,705,153
Consumer Real Estate Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	5,590,180				5,858,821
Permanent Mortgage Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	793,282				788,700
Credit Card And Other Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	299,143				271,730
Commercial Portfolio Segment [Member] | Commercial Financial And Industrial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	8,091,186		8,796,956		7,705,153
Commercial Portfolio Segment [Member] | Income C R E [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	1,062,588		1,109,930		1,247,089
Commercial Portfolio Segment [Member] | Residential C R E [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	53,291		58,305		99,837
Retail [Member] | Consumer Real Estate Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	5,590,180	[1]	5,688,703	[1]	5,858,821	[1]
Retail [Member] | Permanent Mortgage Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	793,282	[2]	765,583	[2]	788,700	[2]
Retail [Member] | Credit Card And Other Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	299,143		289,105		271,730
Restricted Consumer Real Estate Loans And Secured Borrowings [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	386,400		402,400		467,000
Restricted Permanent Mortgage Real Estate Loans And Secured Borrowings [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	$ 13,000		$ 13,200		$ 38,000

[1] Balances as of March 31, 2013 and 2012, and December 31, 2012 include $386.4 million, $467.0 million, and $402.4 million of restricted and secured real estate loans, respectively. See Note 13 - Variable Interest Entities for additional information.

[2] Balances as of March 31, 2013 and 2012, and December 31, 2012 include $13.0 million, $38.0 million and $13.2 million of restricted and secured real estate loans, respectively. See Note 13 - Variable Interest Entities for additional information.