Loans (Composition Of Loan Portfolio By Class Of Loan) (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Financing Receivable, Recorded Investment [Line Items]
Impaired Financing Receivable, Recorded Investment		$ 70,596	$ 96,005	$ 70,596	$ 96,005	$ 73,712
Loan balance		4,900,974		4,900,974		4,829,682
Accrued interest receivable		17,825		17,825		17,677
Recorded Investment		4,914,683		4,914,683		4,843,311
Impaired Financing Receivable, Average Recorded Investment		67,192	99,863	69,468	103,585
Impaired Financing Receivable, Interest Income, Cash Basis Method		542	737	1,104	1,417
Commercial Financial And Agricultural [Member]
Financing Receivable, Recorded Investment [Line Items]
Impaired Financing Receivable, Recorded Investment		20,429	17,628	20,429	17,628
Impaired Financing Receivable, Average Recorded Investment		18,220	18,867	18,830	19,456
Impaired Financing Receivable, Interest Income, Cash Basis Method		140	75	271	136
Construction Real Estate, SEPH Commercial Land and Development [Member]
Financing Receivable, Recorded Investment [Line Items]
Impaired Financing Receivable, Recorded Investment		2,047	4,378	2,047	4,378
Loan balance	[1]	2,141		2,141		2,195
Accrued interest receivable	[1]	0		0		0
Recorded Investment	[1]	2,141		2,141		2,195
Impaired Financing Receivable, Average Recorded Investment		2,068	4,329	2,072	4,439
Impaired Financing Receivable, Interest Income, Cash Basis Method		0	66	8	122
Construction Real Estate - Remaining Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Impaired Financing Receivable, Recorded Investment		6,032	9,954	6,032	9,954
Loan balance		105,229		105,229		115,139
Accrued interest receivable		222		222		300
Recorded Investment		105,451		105,451		115,439
Impaired Financing Receivable, Average Recorded Investment		5,611	10,150	5,644	10,227
Impaired Financing Receivable, Interest Income, Cash Basis Method		6	7	11	54
Construction Real Estate - Mortgage [Member]
Financing Receivable, Recorded Investment [Line Items]
Loan balance		31,493		31,493		31,148
Accrued interest receivable		86		86		72
Recorded Investment		31,579		31,579		31,220
Construction Real Estate - Installment [Member]
Financing Receivable, Recorded Investment [Line Items]
Loan balance		7,108		7,108		7,322
Accrued interest receivable		21		21		23
Recorded Investment		7,129		7,129		7,345
Residential Real Estate - Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Impaired Financing Receivable, Recorded Investment		24,441	28,775	24,441	28,775
Loan balance		417,077		417,077		417,612
Accrued interest receivable		1,024		1,024		1,038
Recorded Investment		418,101		418,101		418,650
Impaired Financing Receivable, Average Recorded Investment		24,443	30,212	24,864	30,577
Impaired Financing Receivable, Interest Income, Cash Basis Method		273	307	528	570
Residential Real Estate - Mortgage [Member]
Financing Receivable, Recorded Investment [Line Items]
Loan balance		1,209,638		1,209,638		1,189,709
Accrued interest receivable		1,789		1,789		1,548
Recorded Investment		1,211,427		1,211,427		1,191,257
Residential Real Estate - HELOC [Member]
Financing Receivable, Recorded Investment [Line Items]
Loan balance		213,301		213,301		216,915
Accrued interest receivable		799		799		803
Recorded Investment		214,100		214,100		217,718
Residential Real Estate - Installment [Member]
Financing Receivable, Recorded Investment [Line Items]
Loan balance		24,705		24,705		27,139
Accrued interest receivable		88		88		97
Recorded Investment		24,793		24,793		27,236
Loans Receivable [Member]
Financing Receivable, Recorded Investment [Line Items]
Accrued interest receivable		13,709		13,709		13,629
Commercial Financial And Agricultural [Member]
Financing Receivable, Recorded Investment [Line Items]
Loan balance	[1]	848,808		848,808		856,535
Accrued interest receivable	[1]	3,042		3,042		3,218
Recorded Investment	[1]	851,850		851,850		859,753
Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Impaired Financing Receivable, Recorded Investment		17,647	35,138	17,647	35,138
Loan balance	[1]	1,087,107		1,087,107		1,069,637
Accrued interest receivable	[1]	3,633		3,633		3,546
Recorded Investment	[1]	1,090,740		1,090,740		1,073,183
Impaired Financing Receivable, Average Recorded Investment		16,850	35,638	18,058	38,163
Impaired Financing Receivable, Interest Income, Cash Basis Method		123	282	286	535
Consumer [Member]
Financing Receivable, Recorded Investment [Line Items]
Impaired Financing Receivable, Recorded Investment			132		132
Loan balance		951,263		951,263		893,160
Accrued interest receivable		2,976		2,976		2,967
Recorded Investment		954,239		954,239		896,127
Impaired Financing Receivable, Average Recorded Investment			667		723
Impaired Financing Receivable, Interest Income, Cash Basis Method		0	$ 0	0	$ 0
Leases [Member]
Financing Receivable, Recorded Investment [Line Items]
Loan balance		3,104		3,104		3,171
Accrued interest receivable		29		29		17
Recorded Investment		$ 3,133		$ 3,133		$ 3,188

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