Loans and Leases - Average Recorded Investment and Analysis of Interest on Impaired Loans (Details 7) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Average recorded investment in impaired loans and an analysis of interest on impaired loans
Average Recorded Investment	$ 42,908	$ 43,234	$ 42,590	$ 42,324
Interest Income Recognized	112	93	175	119
Interest Income That Would Have Been Recognized Under Original Terms	512	653	1,070	1,242
Commercial, financial and agricultural [Member]
Average recorded investment in impaired loans and an analysis of interest on impaired loans
Average Recorded Investment	6,011	6,387	5,596	6,753
Interest Income Recognized	31	12	33	14
Interest Income That Would Have Been Recognized Under Original Terms	60	105	152	193
Real estate-commercial [Member]
Average recorded investment in impaired loans and an analysis of interest on impaired loans
Average Recorded Investment	19,863	16,540	20,421	17,380
Interest Income Recognized	44	49	87	52
Interest Income That Would Have Been Recognized Under Original Terms	257	311	526	561
Real estate-construction [Member]
Average recorded investment in impaired loans and an analysis of interest on impaired loans
Average Recorded Investment	16,639	19,355	16,250	16,986
Interest Income Recognized	35	27	52	28
Interest Income That Would Have Been Recognized Under Original Terms	190	229	385	458
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	161	327	140	380
Interest Income Recognized		1		3
Interest Income That Would Have Been Recognized Under Original Terms	2	3	3	9
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	185	544	130	750
Interest Income Recognized		2		19
Interest Income That Would Have Been Recognized Under Original Terms	3	5	4	20
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		23	4	13
Interest Income Recognized
Interest Income That Would Have Been Recognized Under Original Terms
Loans to individuals [Member]
Average recorded investment in impaired loans and an analysis of interest on impaired loans
Average Recorded Investment	49	58	49	62
Interest Income Recognized	2	2	3	3
Interest Income That Would Have Been Recognized Under Original Terms				$ 1