Loans (Rollforward Of The Allowance For Loan Losses By Portfolio Segment) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning Balance	$ 276,963	$ 384,351
Charge-offs	(36,100)	(57,083)
Recoveries	9,355	10,748
Provision for loan losses	15,000	8,000
Ending Balance	265,218	346,016
Allowance - individually evaluated for impairment	78,867	86,386
Allowance - collectively evaluated for impairment	186,351	259,630
Loans, net of unearned income	15,889,670	15,971,330	16,708,582
Individually evaluated for impairment	457,641	481,959
Collectively evaluated for impairment	15,432,029	15,489,371
Commercial Financial And Industrial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning Balance	96,191	130,413
Charge-offs	(4,436)	(6,074)
Recoveries	2,496	4,514
Provision for loan losses	(8,146)	(9,275)
Ending Balance	86,105	119,578
Allowance - individually evaluated for impairment	15,463	29,147
Allowance - collectively evaluated for impairment	70,642	90,431
Loans, net of unearned income	8,091,186	7,705,153
Individually evaluated for impairment	111,036	151,219
Collectively evaluated for impairment	7,980,150	7,553,934
Commercial Real Estate Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning Balance	19,997	55,586
Charge-offs	(1,381)	(9,619)
Recoveries	646	496
Provision for loan losses	(4,124)	(414)
Ending Balance	15,138	46,049
Allowance - individually evaluated for impairment	156	7,976
Allowance - collectively evaluated for impairment	14,982	38,073
Loans, net of unearned income	1,115,879	1,346,926
Individually evaluated for impairment	43,501	110,123
Collectively evaluated for impairment	1,072,378	1,236,803
Consumer Real Estate Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning Balance	128,949	165,077
Charge-offs	(23,996)	(34,133)
Recoveries	5,504	4,139
Provision for loan losses	20,960	6,564
Ending Balance	131,417	141,647
Allowance - individually evaluated for impairment	40,778	32,300
Allowance - collectively evaluated for impairment	90,639	109,347
Loans, net of unearned income	5,590,180	5,858,821
Individually evaluated for impairment	165,927	117,556
Collectively evaluated for impairment	5,424,253	5,741,265
Permanent Mortgage Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning Balance	24,928	26,194
Charge-offs	(3,387)	(4,638)
Recoveries	144	523
Provision for loan losses	3,763	10,493
Ending Balance	25,448	32,572
Allowance - individually evaluated for impairment	22,239	16,722
Allowance - collectively evaluated for impairment	3,209	15,850
Loans, net of unearned income	793,282	788,700
Individually evaluated for impairment	136,430	102,033
Collectively evaluated for impairment	656,852	686,667
Credit Card And Other Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning Balance	6,898	7,081
Charge-offs	(2,900)	(2,619)
Recoveries	565	1,076
Provision for loan losses	2,547	632
Ending Balance	7,110	6,170
Allowance - individually evaluated for impairment	231	241
Allowance - collectively evaluated for impairment	6,879	5,929
Loans, net of unearned income	299,143	271,730
Individually evaluated for impairment	747	1,028
Collectively evaluated for impairment	$ 298,396	$ 270,702