Loans and Leases - Average Recorded Investment and Analysis of Interest on Impaired Loans (Details 9) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Average recorded investment in impaired loans and an analysis of interest on impaired loans
Average Recorded Investment	$ 43,242	$ 42,806	$ 34,720
Interest Income Recognized	552	261	122
Interest Income that Would Have Been Recognized Under Original Terms	2,161	2,604	2,174
Loans held for sale [Member]
Average recorded investment in impaired loans and an analysis of interest on impaired loans
Average Recorded Investment	592
Interest Income Recognized
Interest Income that Would Have Been Recognized Under Original Terms
Commercial, financial and agricultural [Member]
Average recorded investment in impaired loans and an analysis of interest on impaired loans
Average Recorded Investment	5,189	6,357	3,790
Interest Income Recognized	82	30	13
Interest Income that Would Have Been Recognized Under Original Terms	288	377	234
Real estate-commercial real estate [Member]
Average recorded investment in impaired loans and an analysis of interest on impaired loans
Average Recorded Investment	20,756	18,850	8,280
Interest Income Recognized	348	130	63
Interest Income that Would Have Been Recognized Under Original Terms	1,086	1,300	744
Real estate-construction [Member]
Average recorded investment in impaired loans and an analysis of interest on impaired loans
Average Recorded Investment	16,207	16,720	20,228
Interest Income Recognized	117	64
Interest Income that Would Have Been Recognized Under Original Terms	763	886	1,062
Real estate-residential secured for business purpose [Member]
Average recorded investment in impaired loans and an analysis of interest on impaired loans
Average Recorded Investment	156	306	928
Interest Income Recognized		6	29
Interest Income that Would Have Been Recognized Under Original Terms	7	14	63
Real estate-residential secured for personal purpose [Member]
Average recorded investment in impaired loans and an analysis of interest on impaired loans
Average Recorded Investment	293	491	1,201
Interest Income Recognized		25	13
Interest Income that Would Have Been Recognized Under Original Terms	17	25	62
Real estate-home equity secured for personal purpose [Member]
Average recorded investment in impaired loans and an analysis of interest on impaired loans
Average Recorded Investment	2	25	231
Interest Income Recognized		1
Interest Income that Would Have Been Recognized Under Original Terms		1	9
Loans to individuals [Member]
Average recorded investment in impaired loans and an analysis of interest on impaired loans
Average Recorded Investment	47	57	62
Interest Income Recognized	5	5	4
Interest Income that Would Have Been Recognized Under Original Terms		$ 1