Loans (Composition Of Loan Portfolio, By Class Of Loan) (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2011		Dec. 31, 2010
Financing Receivable, Recorded Investment [Line Items]
Loan balance	$ 4,680,575		$ 4,732,685
Accrued interest receivable	15,269		17,505
Recorded investment	4,695,844		4,750,190
Commercial, Financial And Agricultural [Member]
Financing Receivable, Recorded Investment [Line Items]
Loan balance	756,888	[1]	737,902	[1]
Accrued interest receivable	2,992	[1]	2,886	[1]
Recorded investment	759,880	[1]	740,788	[1]
Construction Real Estate - Vision Commercial Land And Development [Member]
Financing Receivable, Recorded Investment [Line Items]
Loan balance	102,271	[1]	171,334	[1]
Accrued interest receivable	232	[1]	282	[1]
Recorded investment	102,503	[1]	171,616	[1]
Construction Real Estate - Remaining Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Loan balance	163,606		195,693
Accrued interest receivable	341		622
Recorded investment	163,947		196,315
Construction Real Estate - Mortgage [Member]
Financing Receivable, Recorded Investment [Line Items]
Loan balance	19,857		26,326
Accrued interest receivable	62		95
Recorded investment	19,919		26,421
Construction Real Estate - Installment [Member]
Financing Receivable, Recorded Investment [Line Items]
Loan balance	15,007		13,127
Accrued interest receivable	65		54
Recorded investment	15,072		13,181
Residential Real Estate - Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Loan balance	456,670		464,903
Accrued interest receivable	1,276		1,403
Recorded investment	457,946		466,306
Residential Real Estate - Mortgage [Member]
Financing Receivable, Recorded Investment [Line Items]
Loan balance	968,330		906,648
Accrued interest receivable	1,355		2,789
Recorded investment	969,685		909,437
Residential Real Estate - HELOC [Member]
Financing Receivable, Recorded Investment [Line Items]
Loan balance	253,461		260,463
Accrued interest receivable	959		1,014
Recorded investment	254,420		261,477
Residential Real Estate - Installment [Member]
Financing Receivable, Recorded Investment [Line Items]
Loan balance	51,118		60,195
Accrued interest receivable	204		255
Recorded investment	51,322		60,450
Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Loan balance	1,250,936	[1]	1,226,616	[1]
Accrued interest receivable	5,064	[1]	4,804	[1]
Recorded investment	1,256,000	[1]	1,231,420	[1]
Consumer [Member]
Financing Receivable, Recorded Investment [Line Items]
Loan balance	640,267		666,871
Accrued interest receivable	2,679		3,245
Recorded investment	642,946		670,116
Leases [Member]
Financing Receivable, Recorded Investment [Line Items]
Loan balance	2,164		2,607
Accrued interest receivable	40		56
Recorded investment	$ 2,204		$ 2,663

[1] Included within commercial, financial and agricultural loans, commercial real estate loans, and Vision commercial land and development loans are an immaterial amount of consumer loans that are not broken out by class.