Loans (Rollforward Of The Allowance For Loan Losses By Portfolio Segment) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning Balance	$ 265,218	$ 346,016	$ 276,963	$ 384,351
Charge-offs	(30,272)	(49,728)	(66,372)	(106,811)
Recoveries	11,988	9,763	21,343	20,511
Provision for loan losses	15,000	15,000	30,000	23,000
Ending Balance	261,934	321,051	261,934	321,051
Allowance - individually evaluated for impairment	82,111	96,205	82,111	96,205
Allowance - collectively evaluated for impairment	179,823	224,846	179,823	224,846
Individually evaluated for impairment	477,517	494,018	477,517	494,018
Collectively evaluated for impairment	15,677,896	15,691,745	15,677,896	15,691,745
Purchase credit impaired loans	41,633		41,633
Loans, net of unearned income	16,197,046	16,185,763	16,197,046	16,185,763	16,708,582
Commercial Financial And Industrial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning Balance	86,105	119,578	96,191	130,413
Charge-offs	(6,896)	(10,159)	(11,332)	(16,233)
Recoveries	4,101	2,162	6,597	6,676
Provision for loan losses	10,192	(936)	2,046	(10,211)
Ending Balance	93,502	110,645	93,502	110,645
Allowance - individually evaluated for impairment	16,201	31,458	16,201	31,458
Allowance - collectively evaluated for impairment	77,301	79,187	77,301	79,187
Individually evaluated for impairment	118,081	155,863	118,081	155,863
Collectively evaluated for impairment	8,245,494	7,825,502	8,245,494	7,825,502
Purchase credit impaired loans	3,586		3,586
Loans, net of unearned income	8,367,161	7,981,365	8,367,161	7,981,365
Commercial Real Estate Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning Balance	15,138	46,049	19,997	55,586
Charge-offs	(716)	(4,002)	(2,097)	(13,621)
Recoveries	1,470	1,043	2,116	1,539
Provision for loan losses	(1,961)	(1,544)	(6,085)	(1,958)
Ending Balance	13,931	41,546	13,931	41,546
Allowance - individually evaluated for impairment	552	7,707	552	7,707
Allowance - collectively evaluated for impairment	13,379	33,839	13,379	33,839
Individually evaluated for impairment	40,856	92,645	40,856	92,645
Collectively evaluated for impairment	1,140,003	1,221,524	1,140,003	1,221,524
Purchase credit impaired loans	37,347		37,347
Loans, net of unearned income	1,218,206	1,314,169	1,218,206	1,314,169
Consumer Real Estate Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning Balance	131,417	141,647	128,949	165,077
Charge-offs	(18,384)	(29,136)	(42,380)	(63,269)
Recoveries	5,030	5,175	10,534	9,314
Provision for loan losses	2,785	15,735	23,745	22,299
Ending Balance	120,848	133,421	120,848	133,421
Allowance - individually evaluated for impairment	42,393	32,688	42,393	32,688
Allowance - collectively evaluated for impairment	78,455	100,733	78,455	100,733
Individually evaluated for impairment	178,198	125,040	178,198	125,040
Collectively evaluated for impairment	5,370,560	5,730,524	5,370,560	5,730,524
Purchase credit impaired loans	682		682
Loans, net of unearned income	5,549,440	5,855,564	5,549,440	5,855,564
Permanent Mortgage Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning Balance	25,448	32,572	24,928	26,194
Charge-offs	(1,824)	(3,071)	(5,211)	(7,709)
Recoveries	624	648	768	1,171
Provision for loan losses	2,855	(1,037)	6,618	9,456
Ending Balance	27,103	29,112	27,103	29,112
Allowance - individually evaluated for impairment	22,725	24,131	22,725	24,131
Allowance - collectively evaluated for impairment	4,378	4,981	4,378	4,981
Individually evaluated for impairment	139,665	119,537	139,665	119,537
Collectively evaluated for impairment	606,489	636,170	606,489	636,170
Purchase credit impaired loans	0		0
Loans, net of unearned income	746,154	755,707	746,154	755,707
Credit Card And Other Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning Balance	7,110	6,170	6,898	7,081
Charge-offs	(2,452)	(3,360)	(5,352)	(5,979)
Recoveries	763	735	1,328	1,811
Provision for loan losses	1,129	2,782	3,676	3,414
Ending Balance	6,550	6,327	6,550	6,327
Allowance - individually evaluated for impairment	240	221	240	221
Allowance - collectively evaluated for impairment	6,310	6,106	6,310	6,106
Individually evaluated for impairment	717	933	717	933
Collectively evaluated for impairment	315,350	278,025	315,350	278,025
Purchase credit impaired loans	18		18
Loans, net of unearned income	$ 316,085	$ 278,958	$ 316,085	$ 278,958