Loans and Leases - Nonaccrual and Accruing Troubled Debt Restructured Loans and Lease Modifications (Details 2) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Nonaccrual and accruing troubled debt restructured loans and lease modifications
Nonaccrual Loans and Leases	$ 28,887	$ 32,132
Accruing Troubled Debt Restructured Loans and Lease Modifications	13,037	13,457
Total Impaired Loans and Leases	41,924	45,589
Commercial, financial and agricultural [Member]
Nonaccrual and accruing troubled debt restructured loans and lease modifications
Nonaccrual Loans and Leases	1,837	2,842
Accruing Troubled Debt Restructured Loans and Lease Modifications	460	480
Total Impaired Loans and Leases	2,297	3,322
Real estate-commercial [Member]
Nonaccrual and accruing troubled debt restructured loans and lease modifications
Nonaccrual Loans and Leases	12,146	14,340
Accruing Troubled Debt Restructured Loans and Lease Modifications	10,299	10,523
Total Impaired Loans and Leases	22,445	24,863
Real estate-construction [Member]
Nonaccrual and accruing troubled debt restructured loans and lease modifications
Nonaccrual Loans and Leases	13,538	13,588
Accruing Troubled Debt Restructured Loans and Lease Modifications	2,226	2,397
Total Impaired Loans and Leases	15,764	15,985
Real estate-residential secured for business purpose [Member]
Nonaccrual and accruing troubled debt restructured loans and lease modifications
Nonaccrual Loans and Leases	171	172
Accruing Troubled Debt Restructured Loans and Lease Modifications
Total Impaired Loans and Leases	171	172
Real estate-residential secured for personal purpose [Member]
Nonaccrual and accruing troubled debt restructured loans and lease modifications
Nonaccrual Loans and Leases	804	804
Accruing Troubled Debt Restructured Loans and Lease Modifications
Total Impaired Loans and Leases	804	804
Real estate-home equity secured for personal purpose [Member]
Nonaccrual and accruing troubled debt restructured loans and lease modifications
Nonaccrual Loans and Leases	23
Accruing Troubled Debt Restructured Loans and Lease Modifications
Total Impaired Loans and Leases	23
Loans to individuals [Member]
Nonaccrual and accruing troubled debt restructured loans and lease modifications
Nonaccrual Loans and Leases	2
Accruing Troubled Debt Restructured Loans and Lease Modifications	39	38
Total Impaired Loans and Leases	41	38
Lease financings [Member]
Nonaccrual and accruing troubled debt restructured loans and lease modifications
Nonaccrual Loans and Leases	366	386
Accruing Troubled Debt Restructured Loans and Lease Modifications	13	19
Total Impaired Loans and Leases	$ 379	$ 405