Loans (Composition Of Loan Portfolio By Class Of Loan) (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012		Dec. 31, 2011
Financing Receivable, Recorded Investment [Line Items]
Loan balance	$ 4,400,510		$ 4,317,099
Accrued interest receivable	15,145		14,684
Recorded Investment	4,415,655		4,331,783
Construction Real Estate - Vision/SEPH Commercial Land And Development [Member]
Financing Receivable, Recorded Investment [Line Items]
Loan balance	15,809	[1]	31,603	[1]
Accrued interest receivable	17	[1]	31	[1]
Recorded Investment	15,826	[1]	31,634	[1]
Construction Real Estate - Remaining Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Loan balance	138,687		156,053
Accrued interest receivable	360		394
Recorded Investment	139,047		156,447
Construction Real Estate - Mortgage [Member]
Financing Receivable, Recorded Investment [Line Items]
Loan balance	25,791		20,039
Accrued interest receivable	83		64
Recorded Investment	25,874		20,103
Construction Real Estate - Installment [Member]
Financing Receivable, Recorded Investment [Line Items]
Loan balance	8,792		9,851
Accrued interest receivable	35		61
Recorded Investment	8,827		9,912
Residential Real Estate - Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Loan balance	395,703		395,824
Accrued interest receivable	1,080		1,105
Recorded Investment	396,783		396,929
Residential Real Estate - Mortgage [Member]
Financing Receivable, Recorded Investment [Line Items]
Loan balance	1,047,670		953,758
Accrued interest receivable	1,916		1,522
Recorded Investment	1,049,586		955,280
Residential Real Estate - HELOC [Member]
Financing Receivable, Recorded Investment [Line Items]
Loan balance	218,228		227,682
Accrued interest receivable	898		942
Recorded Investment	219,126		228,624
Residential Real Estate - Installment [Member]
Financing Receivable, Recorded Investment [Line Items]
Loan balance	45,402		51,354
Accrued interest receivable	204		236
Recorded Investment	45,606		51,590
Commercial, Financial And Agricultural [Member]
Financing Receivable, Recorded Investment [Line Items]
Loan balance	772,773	[1]	743,797	[1]
Accrued interest receivable	3,384	[1]	3,121	[1]
Recorded Investment	776,157	[1]	746,918	[1]
Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Loan balance	1,081,605	[1]	1,108,574	[1]
Accrued interest receivable	4,369	[1]	4,235	[1]
Recorded Investment	1,085,974	[1]	1,112,809	[1]
Consumer [Member]
Financing Receivable, Recorded Investment [Line Items]
Loan balance	646,612		616,505
Accrued interest receivable	2,751		2,930
Recorded Investment	649,363		619,435
Leases [Member]
Financing Receivable, Recorded Investment [Line Items]
Loan balance	3,438		2,059
Accrued interest receivable	48		43
Recorded Investment	$ 3,486		$ 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.