Loans (Recorded Investment By Loan Grade) (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013		Dec. 31, 2012
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Recorded Investment	$ 4,587,295		$ 4,463,909
Residential Real Estate - Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Recorded Investment	402,801		393,162
Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Recorded Investment	1,119,114	[1]	1,096,003	[1]
Leases [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Recorded Investment	3,370		3,157
5 Rated [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment	48,857		51,292
5 Rated [Member] | SEPH Commercial Land and Development [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment	370	[2]
5 Rated [Member] | SEPH Commercial Land And Development [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment			411	[2]
5 Rated [Member] | Remaining Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment	4,818		6,734
5 Rated [Member] | Residential Real Estate - Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment	7,738		8,994
5 Rated [Member] | Commercial, Financial, and Agricultural [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment	18,956	[2]	9,537	[2]
5 Rated [Member] | Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment	16,975	[2]	25,616	[2]
5 Rated [Member] | Leases [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment	0		0
6 Rated [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment	2,314		16,887
6 Rated [Member] | SEPH Commercial Land and Development [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment	0	[2]
6 Rated [Member] | SEPH Commercial Land And Development [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment			0	[2]
6 Rated [Member] | Remaining Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment	2		0
6 Rated [Member] | Residential Real Estate - Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment	555		2,053
6 Rated [Member] | Commercial, Financial, and Agricultural [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment	710	[2]	10,874	[2]
6 Rated [Member] | Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment	1,047	[2]	3,960	[2]
6 Rated [Member] | Leases [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment	0		0
Impaired [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment	117,490		138,014
Impaired [Member] | SEPH Commercial Land and Development [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment	6,517	[2]
Impaired [Member] | SEPH Commercial Land And Development [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment			13,939	[2]
Impaired [Member] | Remaining Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment	15,606		21,574
Impaired [Member] | Residential Real Estate - Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment	34,477		35,622
Impaired [Member] | Commercial, Financial, and Agricultural [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment	19,881	[2]	22,601	[2]
Impaired [Member] | Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment	41,009	[2]	44,278	[2]
Impaired [Member] | Leases [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment	0		0
Pass Rated [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment	2,278,471		2,243,978
Pass Rated [Member] | SEPH Commercial Land and Development [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment	738	[2]
Pass Rated [Member] | SEPH Commercial Land And Development [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment			792	[2]
Pass Rated [Member] | Remaining Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment	83,696		87,496
Pass Rated [Member] | Residential Real Estate - Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment	360,031		346,493
Pass Rated [Member] | Commercial, Financial, and Agricultural [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment	770,553	[2]	783,891	[2]
Pass Rated [Member] | Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment	1,060,083	[2]	1,022,149	[2]
Pass Rated [Member] | Leases [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment	3,370		3,157
Recorded Investment [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Recorded Investment	2,447,132		2,450,171
Recorded Investment [Member] | SEPH Commercial Land and Development [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Recorded Investment	7,625	[2]
Recorded Investment [Member] | SEPH Commercial Land And Development [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Recorded Investment			15,142	[2]
Recorded Investment [Member] | Remaining Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Recorded Investment	104,122		115,804
Recorded Investment [Member] | Residential Real Estate - Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Recorded Investment	402,801		393,162
Recorded Investment [Member] | Commercial, Financial, and Agricultural [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Recorded Investment	810,100	[2]	826,903	[2]
Recorded Investment [Member] | Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Recorded Investment	1,119,114	[2]	1,096,003	[2]
Recorded Investment [Member] | Leases [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Recorded Investment	$ 3,370		$ 3,157

[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.

[2] * 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.