Loans and Asset Quality Information (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2012
All loans (non-covered and covered):
Amount of loans	$ 2,441,058	$ 2,375,133	$ 2,439,593
Percentage of Loans	100.00%	100.00%	100.00%
Unamortized net deferred loan costs	1,024	1,324	1,478
Loans, total	2,442,082	2,376,457	2,441,071
Commercial, financial and agricultural
All loans (non-covered and covered):
Amount of loans	166,044	160,790	161,846
Percentage of Loans	7.00%	7.00%	7.00%
Real Estate construction, land development and other land loans
All loans (non-covered and covered):
Amount of loans	296,731	298,458	329,375
Percentage of Loans	12.00%	13.00%	13.00%
Real estate mortgage residential (1-4 family) first mortgages
All loans (non-covered and covered):
Amount of loans	839,273	815,281	823,069
Percentage of Loans	34.00%	34.00%	34.00%
Real estate mortgage home equity loans/lines of credit
All loans (non-covered and covered):
Amount of loans	229,559	238,925	243,556
Percentage of Loans	9.00%	10.00%	10.00%
Real estate mortgage commercial and other
All loans (non-covered and covered):
Amount of loans	841,674	789,746	807,914
Percentage of Loans	35.00%	33.00%	33.00%
Installment loans to individual
All loans (non-covered and covered):
Amount of loans	$ 67,777	$ 71,933	$ 73,833
Percentage of Loans	3.00%	3.00%	3.00%