Credit Quality of Loans and Allowance for Loan Losses (Details 2) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011	Sep. 30, 2011
Summarize the past due loans by category
30-59 Days Past Due	$ 2,356	$ 4,220
60-89 Days Past Due	1,828	1,193
Greater than 90 Days	14,804	12,093
Total Past Due	18,988	17,506
Current	497,946	479,036
Gross loans	516,934	496,542	521,626
Real Estate Construction and Land Development [Member]
Summarize the past due loans by category
30-59 Days Past Due	124	447
60-89 Days Past Due	127	198
Greater than 90 Days	4,037	6,142
Total Past Due	4,288	6,787
Current	61,419	60,340
Gross loans	65,707	67,127	71,174
Real Estate Secured by Farmland [Member]
Summarize the past due loans by category
30-59 Days Past Due
60-89 Days Past Due
Greater than 90 Days	357
Total Past Due	357
Current	27,673	29,890
Gross loans	28,030	29,890	31,782
Real Estate Secured by Residential Properties [Member]
Summarize the past due loans by category
30-59 Days Past Due	213	1,055
60-89 Days Past Due	763	993
Greater than 90 Days	1,742	1,278
Total Past Due	2,718	3,326
Current	103,738	107,048
Gross loans	106,456	110,374	117,824
Real Estate Secured by Nonfarm Nonresidential [Member]
Summarize the past due loans by category
30-59 Days Past Due	1,781	2,357
60-89 Days Past Due	933
Greater than 90 Days	8,490	4,446
Total Past Due	11,204	6,803
Current	193,759	196,260
Gross loans	204,963	203,063	211,479
Consumer Installment [Member]
Summarize the past due loans by category
30-59 Days Past Due	1	65
60-89 Days Past Due	3
Greater than 90 Days	6	22
Total Past Due	10	87
Current	6,067	6,533
Gross loans	6,077	6,620	5,354
Credit Cards and Related Plans [Member]
Summarize the past due loans by category
30-59 Days Past Due	3	2
60-89 Days Past Due	2	2
Greater than 90 Days
Total Past Due	5	4
Current	1,550	1,657
Gross loans	1,555	1,661	2,231
Commercial and Industrial [Member]
Summarize the past due loans by category
30-59 Days Past Due	234	294
60-89 Days Past Due
Greater than 90 Days	172	205
Total Past Due	406	499
Current	60,499	45,180
Gross loans	60,905	45,679	44,201
Loans to Finance Agricultural Production [Member]
Summarize the past due loans by category
30-59 Days Past Due
60-89 Days Past Due
Greater than 90 Days
Total Past Due
Current	33,194	21,539
Gross loans	33,194	21,539	20,910
All Other Loans [Member]
Summarize the past due loans by category
30-59 Days Past Due
60-89 Days Past Due
Greater than 90 Days
Total Past Due
Current	10,047	10,589
Gross loans	10,047	10,589	16,671
Non-Accrual Loans Included in above Total [Member]
Summarize the past due loans by category
30-59 Days Past Due	440	1,426
60-89 Days Past Due	1,683	588
Greater than 90 Days	14,804	12,093
Total Past Due	16,927	14,107
Current	1,098	1,866
Gross loans	$ 18,025	$ 15,973