Loans and Leases - Average Recorded Investment and Analysis of Interest on Impaired Loans (Details 7) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Average recorded investment in impaired loans and an analysis of interest on impaired loans
Average Recorded Investment	$ 43,517	$ 45,715	$ 42,847	$ 43,147
Interest Income Recognized	126	62	301	181
Interest Income That Would Have Been Recognized Under Original Terms	525	770	1,595	2,012
Loans held for sale [Member]
Average recorded investment in impaired loans and an analysis of interest on impaired loans
Average Recorded Investment	650		260
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	5,474	5,924	5,542	6,498
Interest Income Recognized	23		56	14
Interest Income That Would Have Been Recognized Under Original Terms	71	77	223	270
Real estate-commercial [Member]
Average recorded investment in impaired loans and an analysis of interest on impaired loans
Average Recorded Investment	20,525	21,497	20,417	18,535
Interest Income Recognized	69	39	156	91
Interest Income That Would Have Been Recognized Under Original Terms	257	463	783	1,024
Real estate-construction [Member]
Average recorded investment in impaired loans and an analysis of interest on impaired loans
Average Recorded Investment	16,324	17,746	16,238	17,104
Interest Income Recognized	33	20	85	48
Interest Income That Would Have Been Recognized Under Original Terms	190	223	575	681
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	176	247	150	343
Interest Income Recognized		2		5
Interest Income That Would Have Been Recognized Under Original Terms	2	4	5	13
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	320	219	188	590
Interest Income Recognized				19
Interest Income That Would Have Been Recognized Under Original Terms	5	3	9	23
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		31	3	18
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	48	51	49	59
Interest Income Recognized	1	1	4	4
Interest Income That Would Have Been Recognized Under Original Terms				$ 1