Loans and Allowance for Loan Losses (Components of loans receivable) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans receivable	$ 528,625	$ 514,682
Percentage of loans receivable	100.00%	100.00%
Individually evaluated for impairment	16,193	32,135
Collectively evaluated for impairment	512,432	482,547
Allowance for loan losses	(7,943)	(12,690)	(12,455)	(16,608)
Deferred loan fees, net of direct origination costs	86	260
Loans receivable, net	520,768	502,252
Weighted average interest rate	5.28%	6.04%
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans receivable	121,307	110,395
Percentage of loans receivable	23.00%	21.40%
Individually evaluated for impairment	6,133	8,585
Collectively evaluated for impairment	115,174	101,810
Allowance for loan losses	(2,156)	(2,817)	(2,925)	(4,785)
Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans receivable	186,844	167,586
Percentage of loans receivable	35.40%	32.60%
Individually evaluated for impairment	3,373	10,918
Collectively evaluated for impairment	183,471	156,668
Allowance for loan losses	(2,762)	(4,880)	(3,655)	(3,827)
Commercial construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans receivable	3,832	6,335
Percentage of loans receivable	0.70%	1.20%
Individually evaluated for impairment	0	747
Collectively evaluated for impairment	3,832	5,588
Allowance for loan losses	(101)	(500)	(540)	(1,671)
Land and land development loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans receivable	31,278	38,499
Percentage of loans receivable	5.90%	7.50%
Individually evaluated for impairment	2,023	5,173
Collectively evaluated for impairment	29,255	33,326
Allowance for loan losses	(1,197)	(2,273)	(2,408)	(2,707)
Agriculture
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans receivable	85,967	81,316
Percentage of loans receivable	16.30%	15.80%
Individually evaluated for impairment	2,134	2,423
Collectively evaluated for impairment	83,833	78,893
Allowance for loan losses	(228)	(172)	(779)	(1,390)
Multifamily
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans receivable	16,544	26,038
Percentage of loans receivable	3.10%	5.10%
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	16,544	26,038
Allowance for loan losses	(51)	(91)	(83)	(26)
Residential real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans receivable	60,020	58,861
Percentage of loans receivable	11.30%	11.40%
Individually evaluated for impairment	2,362	4,013
Collectively evaluated for impairment	57,658	54,848
Allowance for loan losses	(1,144)	(1,566)	(1,252)	(1,412)
Residential construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans receivable	940	2,742
Percentage of loans receivable	0.20%	0.50%
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	940	2,742
Allowance for loan losses	(24)	(59)	(65)	(170)
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans receivable	9,626	11,847
Percentage of loans receivable	1.80%	2.30%
Individually evaluated for impairment	168	276
Collectively evaluated for impairment	9,458	11,571
Allowance for loan losses	(202)	(295)	(613)	(539)
Municipal
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans receivable	12,267	11,063
Percentage of loans receivable	2.30%	2.20%
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	12,267	11,063
Allowance for loan losses	$ (78)	$ (37)	$ (135)	$ (81)