Loans and Allowance for Loan Losses (Schedule Of Current, Accruing Past Due And Nonaccrual Loans) (Details) (USD $)	Sep. 30, 2014		Dec. 31, 2013		Sep. 30, 2013
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	$ 20,302,321,000		$ 19,597,760,000
Accruing 30-89 Days Past Due	68,645,000		68,111,000
Accruing 90 Days or Greater Past Due	4,067,000		4,489,000
Total Accruing Past Due	72,712,000		72,600,000
Non-accrual	242,382,000		416,300,000
Total loans	20,617,415,000	[1]	20,086,660,000	[2]	19,736,612,000
Deferred fees and costs, net	28,800,000		28,900,000		25,000,000
Home Equity Lines [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	1,658,917,000		1,564,578,000
Accruing 30-89 Days Past Due	9,656,000		4,919,000
Accruing 90 Days or Greater Past Due	524,000		136,000
Total Accruing Past Due	10,180,000		5,055,000
Non-accrual	16,875,000		17,908,000
Total loans	1,685,972,000		1,587,541,000
Consumer Mortgages [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	1,574,526,000		1,460,219,000
Accruing 30-89 Days Past Due	11,615,000		18,068,000
Accruing 90 Days or Greater Past Due	1,004,000		1,011,000
Total Accruing Past Due	12,619,000		19,079,000
Non-accrual	34,759,000		39,770,000
Total loans	1,621,904,000		1,519,068,000
Credit Cards [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	250,768,000		253,422,000
Accruing 30-89 Days Past Due	1,688,000		1,917,000
Accruing 90 Days or Greater Past Due	1,397,000		1,507,000
Total Accruing Past Due	3,085,000		3,424,000
Non-accrual	0		0
Total loans	253,853,000		256,846,000
Other Retail Loans [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	288,086,000		280,524,000
Accruing 30-89 Days Past Due	2,747,000		2,190,000
Accruing 90 Days or Greater Past Due	46,000		26,000
Total Accruing Past Due	2,793,000		2,216,000
Non-accrual	2,353,000		2,038,000
Total loans	293,232,000		284,778,000
Investment Properties [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	4,978,360,000		4,546,439,000
Accruing 30-89 Days Past Due	1,565,000		3,552,000
Accruing 90 Days or Greater Past Due	142,000		40,000
Total Accruing Past Due	1,707,000		3,592,000
Non-accrual	38,979,000		66,454,000
Total loans	5,019,046,000		4,616,485,000
1-4 Family Properties [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	1,098,574,000		1,144,447,000
Accruing 30-89 Days Past Due	9,759,000		6,267,000
Accruing 90 Days or Greater Past Due	103,000		527,000
Total Accruing Past Due	9,862,000		6,794,000
Non-accrual	29,118,000		33,819,000
Total loans	1,137,554,000		1,185,060,000
Land Acquisition [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	546,490,000		549,936,000
Accruing 30-89 Days Past Due	2,085,000		1,100,000
Accruing 90 Days or Greater Past Due	76,000		300,000
Total Accruing Past Due	2,161,000		1,400,000
Non-accrual	40,128,000		154,095,000
Total loans	588,779,000		705,431,000
Commercial Real Estate [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	6,623,424,000		6,240,822,000
Accruing 30-89 Days Past Due	13,409,000		10,919,000
Accruing 90 Days or Greater Past Due	321,000		867,000
Total Accruing Past Due	13,730,000		11,786,000
Non-accrual	108,225,000		254,368,000
Total loans	6,745,379,000		6,506,976,000
Commercial, Financial and Agricultural [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	5,935,845,000		5,812,490,000
Accruing 30-89 Days Past Due	13,659,000		18,985,000
Accruing 90 Days or Greater Past Due	545,000		813,000
Total Accruing Past Due	14,204,000		19,798,000
Non-accrual	53,360,000		62,977,000
Total loans	6,003,409,000		5,895,265,000
Owner-Occupied [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	3,970,755,000		3,985,705,000
Accruing 30-89 Days Past Due	15,871,000		11,113,000
Accruing 90 Days or Greater Past Due	230,000		129,000
Total Accruing Past Due	16,101,000		11,242,000
Non-accrual	26,810,000		39,239,000
Total loans	4,013,666,000		4,036,186,000
Commercial and Industrial [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	9,906,600,000		9,798,195,000
Accruing 30-89 Days Past Due	29,530,000		30,098,000
Accruing 90 Days or Greater Past Due	775,000		942,000
Total Accruing Past Due	30,305,000		31,040,000
Non-accrual	80,170,000		102,216,000
Total loans	10,017,075,000		9,931,451,000
Retail [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	3,772,297,000		3,558,743,000
Accruing 30-89 Days Past Due	25,706,000		27,094,000
Accruing 90 Days or Greater Past Due	2,971,000		2,680,000
Total Accruing Past Due	28,677,000		29,774,000
Non-accrual	53,987,000		59,716,000
Total loans	$ 3,854,961,000		$ 3,648,233,000

[1] Total before net deferred fees and costs of $28.8 million.

[2] Total before net deferred fees and costs of $28.9 million.