Loans and Allowance for Loan Losses (Schedule Of Current, Accruing Past Due And Nonaccrual Loans) (Details) (USD $)	Mar. 31, 2014		Dec. 31, 2013		Mar. 31, 2013
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	$ 19,728,078,000		$ 19,597,760,000
Accruing 30-89 Days Past Due	68,475,000		68,111,000
Accruing 90 Days or Greater Past Due	6,563,000		4,489,000
Total Accruing Past Due	75,038,000		72,600,000
Non-accrual	384,324,000		416,300,000
Total loans	20,187,440,000	[1]	20,086,660,000	[2]	19,389,439,000	[3]
Deferred fees and costs, net	28,400,000		28,900,000		21,600,000
Home Equity Lines [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	1,578,593,000		1,564,578,000
Accruing 30-89 Days Past Due	5,090,000		4,919,000
Accruing 90 Days or Greater Past Due	71,000		136,000
Total Accruing Past Due	5,161,000		5,055,000
Non-accrual	18,003,000		17,908,000
Total loans	1,601,757,000		1,587,541,000
Consumer Mortgages [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	1,448,207,000		1,460,219,000
Accruing 30-89 Days Past Due	17,720,000		18,068,000
Accruing 90 Days or Greater Past Due	59,000		1,011,000
Total Accruing Past Due	17,779,000		19,079,000
Non-accrual	38,227,000		39,770,000
Total loans	1,504,213,000		1,519,068,000
Credit Cards [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	249,546,000		253,422,000
Accruing 30-89 Days Past Due	1,997,000		1,917,000
Accruing 90 Days or Greater Past Due	1,606,000		1,507,000
Total Accruing Past Due	3,603,000		3,424,000
Non-accrual	0		0
Total loans	253,149,000		256,846,000
Other Retail Loans [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	274,552,000		280,524,000
Accruing 30-89 Days Past Due	2,748,000		2,190,000
Accruing 90 Days or Greater Past Due	59,000		26,000
Total Accruing Past Due	2,807,000		2,216,000
Non-accrual	2,427,000		2,038,000
Total loans	279,786,000		284,778,000
Investment Properties [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	4,645,364,000		4,533,708,000
Accruing 30-89 Days Past Due	2,522,000		3,552,000
Accruing 90 Days or Greater Past Due	0		40,000
Total Accruing Past Due	2,522,000		3,592,000
Non-accrual	50,583,000		66,454,000
Total loans	4,698,469,000		4,603,754,000
1-4 Family Properties [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	1,075,831,000		1,115,858,000
Accruing 30-89 Days Past Due	5,932,000		6,267,000
Accruing 90 Days or Greater Past Due	1,998,000		527,000
Total Accruing Past Due	7,930,000		6,794,000
Non-accrual	29,251,000		33,819,000
Total loans	1,113,012,000		1,156,471,000
Land Acquisition [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	519,669,000		549,838,000
Accruing 30-89 Days Past Due	3,619,000		1,100,000
Accruing 90 Days or Greater Past Due	58,000		300,000
Total Accruing Past Due	3,677,000		1,400,000
Non-accrual	151,332,000		154,095,000
Total loans	674,678,000		705,333,000
Commercial Real Estate [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	6,240,864,000		6,199,404,000
Accruing 30-89 Days Past Due	12,073,000		10,919,000
Accruing 90 Days or Greater Past Due	2,056,000		867,000
Total Accruing Past Due	14,129,000		11,786,000
Non-accrual	231,166,000		254,368,000
Total loans	6,486,159,000		6,465,558,000
Commercial, Financial and Agricultural [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	5,433,948,000		5,413,614,000
Accruing 30-89 Days Past Due	14,896,000		16,251,000
Accruing 90 Days or Greater Past Due	1,795,000		721,000
Total Accruing Past Due	16,691,000		16,972,000
Non-accrual	54,938,000		59,628,000
Total loans	5,505,577,000		5,490,214,000
Owner-Occupied [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	3,732,210,000		3,749,052,000
Accruing 30-89 Days Past Due	7,303,000		9,341,000
Accruing 90 Days or Greater Past Due	905,000		66,000
Total Accruing Past Due	8,208,000		9,407,000
Non-accrual	33,238,000		36,980,000
Total loans	3,773,656,000		3,795,439,000
Small Business [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	770,158,000		676,947,000
Accruing 30-89 Days Past Due	6,648,000		4,506,000
Accruing 90 Days or Greater Past Due	12,000		155,000
Total Accruing Past Due	6,660,000		4,661,000
Non-accrual	6,325,000		5,608,000
Total loans	783,143,000		687,216,000
Commercial and Industrial [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	9,936,316,000		9,839,613,000
Accruing 30-89 Days Past Due	28,847,000		30,098,000
Accruing 90 Days or Greater Past Due	2,712,000		942,000
Total Accruing Past Due	31,559,000		31,040,000
Non-accrual	94,501,000		102,216,000
Total loans	10,062,376,000		9,972,869,000
Retail [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	3,550,898,000		3,558,743,000
Accruing 30-89 Days Past Due	27,555,000		27,094,000
Accruing 90 Days or Greater Past Due	1,795,000		2,680,000
Total Accruing Past Due	29,350,000		29,774,000
Non-accrual	58,657,000		59,716,000
Total loans	$ 3,638,905,000		$ 3,648,233,000

[1] Total before net deferred fees and costs of $28.4 million.

[2] Total before net deferred fees and costs of

[3] Total before net deferred fees and costs of $21.6 million.