Credit Quality of Loans and Allowance for Loan Losses (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011	Dec. 31, 2011
Financing receivable allowance for credit losses and additional information
Beginning balance	$ 11,385	$ 15,219	$ 12,092	$ 13,247
Charge-offs	(1,651)	(1,088)	(2,663)	(3,148)
Recoveries	180	44	485	146
Provisions	866	1,273	866	5,203
Ending balance	10,780	15,448	10,780	15,448
Ending Balance: individually evaluated for impairment	1,392	4,059	1,392	4,059
Ending Balance: collectively evaluated for impairment	9,388	11,389	9,388	11,389
Loans
Ending Balance	506,257	542,687	506,257	542,687	496,542
Ending Balance: individually evaluated for impairment	32,277	31,312	32,277	31,312
Ending Balance: collectively evaluated for impairment	473,980	511,375	473,980	511,375
Real estate-construction and land development
Financing receivable allowance for credit losses and additional information
Beginning balance	3,100	7,587	3,655	6,168
Charge-offs	(694)	(644)	(913)	(1,917)
Recoveries	111	6	337	6
Provisions	738	518	176	3,210
Ending balance	3,255	7,467	3,255	7,467
Ending Balance: individually evaluated for impairment	575	1,931	575	1,931
Ending Balance: collectively evaluated for impairment	2,680	5,536	2,680	5,536
Loans
Ending Balance	62,944	84,291	62,944	84,291	67,127
Ending Balance: individually evaluated for impairment	8,797	16,331	8,797	16,331
Ending Balance: collectively evaluated for impairment	54,147	67,960	54,147	67,960
Real Estate Secured by Farmland [Member]
Financing receivable allowance for credit losses and additional information
Beginning balance	15	29	15	28
Charge-offs
Recoveries
Provisions	(2)	4	(2)	5
Ending balance	13	33	13	33
Ending Balance: individually evaluated for impairment
Ending Balance: collectively evaluated for impairment	13	33	13	33
Loans
Ending Balance	27,627	33,641	27,627	33,641	29,890
Ending Balance: individually evaluated for impairment	356		356
Ending Balance: collectively evaluated for impairment	27,271	33,641	27,271	33,641
Real estate-secured by residential properties
Financing receivable allowance for credit losses and additional information
Beginning balance	2,486	4,002	2,418	3,450
Charge-offs	(176)	(255)	(278)	(704)
Recoveries	20	1	47	2
Provisions	59	491	202	1,491
Ending balance	2,389	4,239	2,389	4,239
Ending Balance: individually evaluated for impairment	617	1,124	617	1,124
Ending Balance: collectively evaluated for impairment	1,772	3,115	1,772	3,115
Loans
Ending Balance	107,695	117,458	107,695	117,458	110,374
Ending Balance: individually evaluated for impairment	7,614	8,762	7,614	8,762
Ending Balance: collectively evaluated for impairment	100,081	108,696	100,081	108,696
Real estate-secured by nonfarm nonresidential properties
Financing receivable allowance for credit losses and additional information
Beginning balance	1,565	1,118	1,740	1,007
Charge-offs	(654)	(43)	(892)	(43)
Recoveries	1		2
Provisions	138	57	200	168
Ending balance	1,050	1,132	1,050	1,132
Ending Balance: individually evaluated for impairment	180	585	180	585
Ending Balance: collectively evaluated for impairment	870	547	870	547
Loans
Ending Balance	198,007	211,556	198,007	211,556	203,063
Ending Balance: individually evaluated for impairment	15,093	5,508	15,093	5,508
Ending Balance: collectively evaluated for impairment	182,914	206,048	182,914	206,048
Consumer Installment [Member]
Financing receivable allowance for credit losses and additional information
Beginning balance	150	16	46	12
Charge-offs	(2)	(6)	(43)	(15)
Recoveries	12		13	2
Provisions	(10)	20	134	31
Ending balance	150	30	150	30
Ending Balance: individually evaluated for impairment
Ending Balance: collectively evaluated for impairment	150	30	150	30
Loans
Ending Balance	6,160	5,191	6,160	5,191	6,620
Ending Balance: individually evaluated for impairment
Ending Balance: collectively evaluated for impairment	6,160	5,191	6,160	5,191
Credit Cards and Related Plans [Member]
Financing receivable allowance for credit losses and additional information
Beginning balance	68	189	18	21
Charge-offs	(14)		(17)	(9)
Recoveries	3	1	3	1
Provisions	12	(2)	65	175
Ending balance	69	188	69	188
Ending Balance: individually evaluated for impairment		170		170
Ending Balance: collectively evaluated for impairment	69	18	69	18
Loans
Ending Balance	1,723	2,422	1,723	2,422	1,661
Ending Balance: individually evaluated for impairment		200		200
Ending Balance: collectively evaluated for impairment	1,723	2,222	1,723	2,222
Commercial and Industrial [Member]
Financing receivable allowance for credit losses and additional information
Beginning balance	505	1,132	555	882
Charge-offs	(64)	(84)	(421)	(338)
Recoveries	2	15	12	78
Provisions	208	(441)	505
Ending balance	651	622	651	622
Ending Balance: individually evaluated for impairment	20	249	20	249
Ending Balance: collectively evaluated for impairment	631	373	631	373
Loans
Ending Balance	55,005	47,780	55,005	47,780	45,679
Ending Balance: individually evaluated for impairment	417	511	417	511
Ending Balance: collectively evaluated for impairment	54,588	47,269	54,588	47,269
Loans to Finance Agricultural Production [Member]
Financing receivable allowance for credit losses and additional information
Beginning balance	122	15	115	18
Charge-offs
Recoveries
Provisions	(21)		(14)	(3)
Ending balance	101	15	101	15
Ending Balance: individually evaluated for impairment
Ending Balance: collectively evaluated for impairment	101	15	101	15
Loans
Ending Balance	36,856	23,715	36,856	23,715	21,539
Ending Balance: individually evaluated for impairment
Ending Balance: collectively evaluated for impairment	36,856	23,715	36,856	23,715
All Other Loans [Member]
Financing receivable allowance for credit losses and additional information
Beginning balance	28	130	26	139
Charge-offs	(47)	(56)	(99)	(122)
Recoveries	31	21	71	57
Provisions	27	79	41	100
Ending balance	39	174	39	174
Ending Balance: individually evaluated for impairment
Ending Balance: collectively evaluated for impairment	39	174	39	174
Loans
Ending Balance	10,240	16,633	10,240	16,633	10,589
Ending Balance: individually evaluated for impairment
Ending Balance: collectively evaluated for impairment	10,240	16,633	10,240	16,633
General Qualitative & Quantitative Portion [Member]
Financing receivable allowance for credit losses and additional information
Beginning balance	3,346	1,001	3,504	1,522
Charge-offs
Recoveries
Provisions	(283)	547	(441)	26
Ending balance	3,063	1,548	3,063	1,548
Ending Balance: individually evaluated for impairment
Ending Balance: collectively evaluated for impairment	3,063	1,548	3,063	1,548
Loans
Ending Balance
Ending Balance: individually evaluated for impairment
Ending Balance: collectively evaluated for impairment