Loans (Composition Of Loan Portfolio By Class Of Loan) (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012		Dec. 31, 2011
Financing Receivable, Recorded Investment [Line Items]
Loan balance	$ 4,386,851		$ 4,317,099
Accrued interest receivable	14,092		14,684
Recorded Investment	4,400,943		4,331,783
Construction Real Estate - Vision/SEPH LLC Commercial Land And Development [Member]
Financing Receivable, Recorded Investment [Line Items]
Loan balance	21,004	[1]	31,603	[1]
Accrued interest receivable	1	[1]	31	[1]
Recorded Investment	21,005	[1]	31,634	[1]
Construction Real Estate - Remaining Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Loan balance	143,782		156,053
Accrued interest receivable	398		394
Recorded Investment	144,180		156,447
Construction Real Estate - Mortgage [Member]
Financing Receivable, Recorded Investment [Line Items]
Loan balance	22,954		20,039
Accrued interest receivable	73		64
Recorded Investment	23,027		20,103
Construction Real Estate - Installment [Member]
Financing Receivable, Recorded Investment [Line Items]
Loan balance	8,977		9,851
Accrued interest receivable	46		61
Recorded Investment	9,023		9,912
Residential Real Estate - Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Loan balance	392,547		395,824
Accrued interest receivable	758		1,105
Recorded Investment	393,305		396,929
Residential Real Estate - Mortgage [Member]
Financing Receivable, Recorded Investment [Line Items]
Loan balance	1,039,189		953,758
Accrued interest receivable	1,660		1,522
Recorded Investment	1,040,849		955,280
Residential Real Estate - HELOC [Member]
Financing Receivable, Recorded Investment [Line Items]
Loan balance	219,084		227,682
Accrued interest receivable	887		942
Recorded Investment	219,971		228,624
Residential Real Estate - Installment [Member]
Financing Receivable, Recorded Investment [Line Items]
Loan balance	47,036		51,354
Accrued interest receivable	218		236
Recorded Investment	47,254		51,590
Commercial, Financial And Agricultural [Member]
Financing Receivable, Recorded Investment [Line Items]
Loan balance	771,702	[1]	743,797	[1]
Accrued interest receivable	3,478	[1]	3,121	[1]
Recorded Investment	775,180	[1]	746,918	[1]
Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Loan balance	1,093,748	[1]	1,108,574	[1]
Accrued interest receivable	3,840	[1]	4,235	[1]
Recorded Investment	1,097,588	[1]	1,112,809	[1]
Consumer [Member]
Financing Receivable, Recorded Investment [Line Items]
Loan balance	623,288		616,505
Accrued interest receivable	2,704		2,930
Recorded Investment	625,992		619,435
Leases [Member]
Financing Receivable, Recorded Investment [Line Items]
Loan balance	3,540		2,059
Accrued interest receivable	29		43
Recorded Investment	$ 3,569		$ 2,102

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