Loans (Schedule Of Loans By Portfolio Segment) (Details) - USD ($) $ in Thousands	Mar. 31, 2017		Dec. 31, 2016		Mar. 31, 2016	Dec. 31, 2015
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	$ 19,090,074	[1]	$ 19,589,520	[1]	$ 17,574,994
Allowance for loan losses	201,968		202,068		204,034	$ 210,242
Total net loans	18,888,106		19,387,452
Commercial Financial And Industrial Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	11,703,996		12,148,087		10,239,183
Allowance for loan losses	93,107		89,398		80,887	73,637
Commercial Real Estate Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	2,173,311		2,135,523		1,848,569
Allowance for loan losses	30,888		33,852		25,626	25,159
Consumer Real Estate Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	4,456,811	[2]	4,523,752	[2]	4,690,230
Allowance for loan losses	49,680		50,357		67,321	80,614
Permanent Mortgage Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	409,235		423,125		442,791
Allowance for loan losses	15,893		16,289		18,754	18,947
Credit Card And Other Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	346,721		359,033		354,221
Allowance for loan losses	12,400		12,172		$ 11,446	$ 11,885
Restricted And Secured Consumer Real Estate Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	$ 32,500		$ 35,900

[1] March 31, 2017 and December 31, 2016 include $30.3 million and $28.5 million, respectively, of held-to-maturity consumer mortgage loans se cured by residential real estate properties in process of foreclosure.

[2] Balances as of March 3 1 , 201 7 and December 31, 201 6 , include $ 32 . 5 million and $ 35 . 9 million of restricted real estate loans, respectively. See Note 13 - Variable Interest Entities for additional information.