Allowance For Loan Losses (Rollforward Of The Allowance For Loan Losses By Portfolio Segment) (Details) (USD $)	3 Months Ended				9 Months Ended
	Sep. 30, 2014		Sep. 30, 2013		Sep. 30, 2014		Sep. 30, 2013		Dec. 31, 2013
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning Balance	$ 243,628,000		$ 261,934,000		$ 253,809,000		$ 276,963,000
Charge-offs	(23,684,000)		(26,046,000)		(67,140,000)		(92,418,000)
Recoveries	12,697,000		9,822,000		30,972,000		31,165,000
Provision for loan losses	6,000,000		10,000,000		21,000,000		40,000,000
Ending Balance	238,641,000		255,710,000		238,641,000		255,710,000
Allowance - individually evaluated for impairment	66,219,000		74,567,000		66,219,000		74,567,000
Allowance - collectively evaluated for impairment	169,583,000		181,143,000		169,583,000		181,143,000
Allowance - purchased credit-impaired loans	2,839,000				2,839,000
Individually evaluated for impairment	362,844,000		432,168,000		362,844,000		432,168,000
Collectively evaluated for impairment	15,409,050,000		14,928,128,000		15,409,050,000		14,928,128,000
Purchased credit-impaired loans - recorded investment	40,123,000		48,260,000	[1]	40,123,000		48,260,000	[1]
Loans, net of unearned income	15,812,017,000		15,408,556,000		15,812,017,000		15,408,556,000		15,389,074,000
Commercial Financial And Industrial Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning Balance	68,591,000		93,502,000		86,446,000		96,191,000
Charge-offs	(3,741,000)		(4,869,000)		(14,997,000)		(16,201,000)
Recoveries	5,219,000		3,242,000		8,338,000		9,839,000
Provision for loan losses	(199,000)		(495,000)		(9,917,000)		1,551,000
Ending Balance	69,870,000		91,380,000		69,870,000		91,380,000
Allowance - individually evaluated for impairment	6,039,000		15,702,000		6,039,000		15,702,000
Allowance - collectively evaluated for impairment	63,783,000		75,678,000		63,783,000		75,678,000
Allowance - purchased credit-impaired loans	48,000				48,000
Individually evaluated for impairment	46,862,000		102,729,000		46,862,000		102,729,000
Collectively evaluated for impairment	8,425,391,000		7,636,501,000		8,425,391,000		7,636,501,000
Purchased credit-impaired loans - recorded investment	5,076,000		7,712,000	[1]	5,076,000		7,712,000	[1]
Loans, net of unearned income	8,477,329,000		7,746,942,000		8,477,329,000		7,746,942,000		7,923,576,000
Commercial Real Estate Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning Balance	15,821,000		13,931,000		10,603,000		19,997,000
Charge-offs	(1,789,000)		(515,000)		(3,163,000)		(2,612,000)
Recoveries	312,000		587,000		2,323,000		2,703,000
Provision for loan losses	1,106,000		(3,010,000)		5,687,000		(9,095,000)
Ending Balance	15,450,000		10,993,000		15,450,000		10,993,000
Allowance - individually evaluated for impairment	1,104,000		1,581,000		1,104,000		1,581,000
Allowance - collectively evaluated for impairment	11,613,000		9,412,000		11,613,000		9,412,000
Allowance - purchased credit-impaired loans	2,733,000				2,733,000
Individually evaluated for impairment	22,365,000		30,266,000		22,365,000		30,266,000
Collectively evaluated for impairment	1,221,636,000		1,103,800,000		1,221,636,000		1,103,800,000
Purchased credit-impaired loans - recorded investment	34,393,000		39,645,000	[1]	34,393,000		39,645,000	[1]
Loans, net of unearned income	1,278,394,000		1,173,711,000		1,278,394,000		1,173,711,000		1,133,279,000
Consumer Real Estate Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning Balance	118,037,000		120,848,000		126,785,000		128,949,000
Charge-offs	(13,465,000)		(16,412,000)		(33,803,000)		(58,792,000)
Recoveries	5,669,000		4,398,000		16,113,000		14,932,000
Provision for loan losses	8,154,000		11,992,000		9,300,000		35,737,000
Ending Balance	118,395,000		120,826,000		118,395,000		120,826,000
Allowance - individually evaluated for impairment	41,492,000		38,426,000		41,492,000		38,426,000
Allowance - collectively evaluated for impairment	76,845,000		82,400,000		76,845,000		82,400,000
Allowance - purchased credit-impaired loans	58,000				58,000
Individually evaluated for impairment	174,532,000		170,401,000		174,532,000		170,401,000
Collectively evaluated for impairment	4,955,813,000		5,286,758,000		4,955,813,000		5,286,758,000
Purchased credit-impaired loans - recorded investment	643,000		888,000	[1]	643,000		888,000	[1]
Loans, net of unearned income	5,130,988,000	[2]	5,458,047,000	[2]	5,130,988,000	[2]	5,458,047,000	[2]	5,333,371,000	[2]
Permanent Mortgage Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning Balance	23,727,000		27,103,000		22,491,000		24,928,000
Charge-offs	(1,047,000)		(1,366,000)		(4,144,000)		(6,577,000)
Recoveries	686,000		841,000		1,958,000		1,609,000
Provision for loan losses	(3,145,000)		(1,022,000)		(84,000)		5,596,000
Ending Balance	20,221,000		25,556,000		20,221,000		25,556,000
Allowance - individually evaluated for impairment	17,329,000		18,646,000		17,329,000		18,646,000
Allowance - collectively evaluated for impairment	2,892,000		6,910,000		2,892,000		6,910,000
Allowance - purchased credit-impaired loans	0				0
Individually evaluated for impairment	118,537,000		128,124,000		118,537,000		128,124,000
Collectively evaluated for impairment	454,252,000		569,570,000		454,252,000		569,570,000
Purchased credit-impaired loans - recorded investment	0		0		0		0
Loans, net of unearned income	572,789,000		697,694,000	[3]	572,789,000		697,694,000	[3]	662,242,000	[3]
Credit Card And Other Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning Balance	17,452,000		6,550,000		7,484,000		6,898,000
Charge-offs	(3,642,000)		(2,884,000)		(11,033,000)		(8,236,000)
Recoveries	811,000		754,000		2,240,000		2,082,000
Provision for loan losses	84,000		2,535,000		16,014,000		6,211,000
Ending Balance	14,705,000		6,955,000		14,705,000		6,955,000
Allowance - individually evaluated for impairment	255,000		212,000		255,000		212,000
Allowance - collectively evaluated for impairment	14,450,000		6,743,000		14,450,000		6,743,000
Allowance - purchased credit-impaired loans	0				0
Individually evaluated for impairment	548,000		648,000		548,000		648,000
Collectively evaluated for impairment	351,958,000		331,499,000		351,958,000		331,499,000
Purchased credit-impaired loans - recorded investment	11,000		15,000		11,000		15,000
Loans, net of unearned income	$ 352,517,000		$ 332,162,000		$ 352,517,000		$ 332,162,000		$ 336,606,000

[1] September 30, 2013balances by portfolio have been re-presented to agree with current presentation.

[2] Balances as of September 30, 2014 and 2013, and December 31, 2013 include $81.1 million, $349.3 million, and $333.8 million of restricted and secured real estate loans, respectively. See Note 14 - Variable Interest Entities for additional information.

[3] Balances as of September 30, 2013, and December 31, 2013 include $11.7 million and $11.2 million of restricted and secured real estate loans, respectively. See Note 14 - Variable Interest Entities for additional information.