Loans and Allowance for Loan Losses (Schedule Of Current, Accruing Past Due And Nonaccrual Loans) (Details) (USD $)	Jun. 30, 2014		Dec. 31, 2013		Jun. 30, 2013
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	$ 20,164,743,000		$ 19,597,760,000
Accruing 30-89 Days Past Due	55,630,000		68,111,000
Accruing 90 Days or Greater Past Due	4,798,000		4,489,000
Total Accruing Past Due	60,428,000		72,600,000
Non-accrual	259,547,000		416,300,000
Total loans	20,484,718,000	[1]	20,086,660,000	[2]	19,632,050,000
Deferred fees and costs, net	29,000,000		28,900,000		23,800,000
Home Equity Lines [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	1,641,202,000		1,564,578,000
Accruing 30-89 Days Past Due	6,781,000		4,919,000
Accruing 90 Days or Greater Past Due	141,000		136,000
Total Accruing Past Due	6,922,000		5,055,000
Non-accrual	16,396,000		17,908,000
Total loans	1,664,520,000		1,587,541,000
Consumer Mortgages [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	1,512,811,000		1,460,219,000
Accruing 30-89 Days Past Due	11,652,000		18,068,000
Accruing 90 Days or Greater Past Due	215,000		1,011,000
Total Accruing Past Due	11,867,000		19,079,000
Non-accrual	36,433,000		39,770,000
Total loans	1,561,111,000		1,519,068,000
Credit Cards [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	252,538,000		253,422,000
Accruing 30-89 Days Past Due	1,502,000		1,917,000
Accruing 90 Days or Greater Past Due	1,329,000		1,507,000
Total Accruing Past Due	2,831,000		3,424,000
Non-accrual	0		0
Total loans	255,369,000		256,846,000
Other Retail Loans [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	283,030,000		280,524,000
Accruing 30-89 Days Past Due	2,444,000		2,190,000
Accruing 90 Days or Greater Past Due	63,000		26,000
Total Accruing Past Due	2,507,000		2,216,000
Non-accrual	2,398,000		2,038,000
Total loans	287,935,000		284,778,000
Investment Properties [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	4,767,934,000		4,533,708,000
Accruing 30-89 Days Past Due	1,488,000		3,552,000
Accruing 90 Days or Greater Past Due	0		40,000
Total Accruing Past Due	1,488,000		3,592,000
Non-accrual	40,927,000		66,454,000
Total loans	4,810,349,000		4,603,754,000
1-4 Family Properties [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	1,026,506,000		1,115,858,000
Accruing 30-89 Days Past Due	5,455,000		6,267,000
Accruing 90 Days or Greater Past Due	417,000		527,000
Total Accruing Past Due	5,872,000		6,794,000
Non-accrual	26,711,000		33,819,000
Total loans	1,059,089,000		1,156,471,000
Land Acquisition [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	553,949,000		549,838,000
Accruing 30-89 Days Past Due	1,695,000		1,100,000
Accruing 90 Days or Greater Past Due	347,000		300,000
Total Accruing Past Due	2,042,000		1,400,000
Non-accrual	42,564,000		154,095,000
Total loans	598,555,000		705,333,000
Commercial Real Estate [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	6,348,389,000		6,199,404,000
Accruing 30-89 Days Past Due	8,638,000		10,919,000
Accruing 90 Days or Greater Past Due	764,000		867,000
Total Accruing Past Due	9,402,000		11,786,000
Non-accrual	110,202,000		254,368,000
Total loans	6,467,993,000		6,465,558,000
Commercial, Financial and Agricultural [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	5,504,255,000		5,413,614,000
Accruing 30-89 Days Past Due	11,977,000		16,251,000
Accruing 90 Days or Greater Past Due	806,000		721,000
Total Accruing Past Due	12,783,000		16,972,000
Non-accrual	57,903,000		59,628,000
Total loans	5,574,941,000		5,490,214,000
Owner-Occupied [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	3,748,944,000		3,749,052,000
Accruing 30-89 Days Past Due	7,502,000		9,341,000
Accruing 90 Days or Greater Past Due	828,000		66,000
Total Accruing Past Due	8,330,000		9,407,000
Non-accrual	29,005,000		36,980,000
Total loans	3,786,279,000		3,795,439,000
Small Business [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	873,574,000		676,947,000
Accruing 30-89 Days Past Due	5,134,000		4,506,000
Accruing 90 Days or Greater Past Due	652,000		155,000
Total Accruing Past Due	5,786,000		4,661,000
Non-accrual	7,210,000		5,608,000
Total loans	886,570,000		687,216,000
Commercial and Industrial [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	10,126,773,000		9,839,613,000
Accruing 30-89 Days Past Due	24,613,000		30,098,000
Accruing 90 Days or Greater Past Due	2,286,000		942,000
Total Accruing Past Due	26,899,000		31,040,000
Non-accrual	94,118,000		102,216,000
Total loans	10,247,790,000		9,972,869,000
Retail [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	3,689,581,000		3,558,743,000
Accruing 30-89 Days Past Due	22,379,000		27,094,000
Accruing 90 Days or Greater Past Due	1,748,000		2,680,000
Total Accruing Past Due	24,127,000		29,774,000
Non-accrual	55,227,000		59,716,000
Total loans	$ 3,768,935,000		$ 3,648,233,000

[1] Total before net deferred fees and costs of $29.0 million.

[2] Total before net deferred fees and costs of