Loans (Recorded Investment By Loan Grade) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013		Dec. 31, 2012
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Recorded Investment	$ 4,458,064		$ 4,463,909
Residential Real Estate - Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Recorded Investment	401,408		393,162
Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Recorded Investment	1,112,999	[1]	1,096,003	[1]
Leases [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Recorded Investment	3,471		3,157
5 Rated [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment	49,267		51,292
5 Rated [Member] | SEPH Commercial Land and Development [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment	400	[2]
5 Rated [Member] | Vision 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	6,556		6,734
5 Rated [Member] | Residential Real Estate - Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment	8,676		8,994
5 Rated [Member] | Commercial, Financial, and Agricultural [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment	8,233	[2]	9,537	[2]
5 Rated [Member] | Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment	25,402	[2]	25,616	[2]
5 Rated [Member] | Leases [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment
6 Rated [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment	14,164		16,887
6 Rated [Member] | SEPH Commercial Land and Development [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment		[2]
6 Rated [Member] | Vision Commercial Land And Development [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment				[2]
6 Rated [Member] | Remaining Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment
6 Rated [Member] | Residential Real Estate - Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment	1,231		2,053
6 Rated [Member] | Commercial, Financial, and Agricultural [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment	9,797	[2]	10,874	[2]
6 Rated [Member] | Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment	3,136	[2]	3,960	[2]
6 Rated [Member] | Leases [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment
Impaired [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment	130,166		138,014
Impaired [Member] | SEPH Commercial Land and Development [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment	11,133	[2]
Impaired [Member] | Vision 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	20,483		21,574
Impaired [Member] | Residential Real Estate - Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment	36,722		35,622
Impaired [Member] | Commercial, Financial, and Agricultural [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment	21,753	[2]	22,601	[2]
Impaired [Member] | Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment	40,075	[2]	44,278	[2]
Impaired [Member] | Leases [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment
Pass Rated [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment	2,252,346		2,243,978
Pass Rated [Member] | SEPH Commercial Land and Development [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment	778	[2]
Pass Rated [Member] | Vision 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	88,835		87,496
Pass Rated [Member] | Residential Real Estate - Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment	354,779		346,493
Pass Rated [Member] | Commercial, Financial, and Agricultural [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment	760,097	[2]	783,891	[2]
Pass Rated [Member] | Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment	1,044,386	[2]	1,022,149	[2]
Pass Rated [Member] | Leases [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loan balance, recorded investment	3,471		3,157
Recorded Investment [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Recorded Investment	2,445,943		2,450,171
Recorded Investment [Member] | SEPH Commercial Land and Development [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Recorded Investment	12,311	[2]
Recorded Investment [Member] | Vision 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	115,874		115,804
Recorded Investment [Member] | Residential Real Estate - Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Recorded Investment	401,408		393,162
Recorded Investment [Member] | Commercial, Financial, and Agricultural [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Recorded Investment	799,880	[2]	826,903	[2]
Recorded Investment [Member] | Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Recorded Investment	1,112,999	[2]	1,096,003	[2]
Recorded Investment [Member] | Leases [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Recorded Investment	$ 3,471		$ 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.