Loans and Allowance for Loan Losses (Aging of loan receivables) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	$ 521,409	$ 503,959
30 to 89 days past due	687	1,431
90 days past due and accruing	0	0
Nonaccrual	6,529	9,292
Total loans receivable	528,625	514,682
Commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	117,096	106,509
30 to 89 days past due	169	200
90 days past due and accruing	0	0
Nonaccrual	4,042	3,686
Total loans receivable	121,307	110,395
Commercial real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	185,128	164,578
30 to 89 days past due	0	705
90 days past due and accruing	0	0
Nonaccrual	1,716	2,303
Total loans receivable	186,844	167,586
Commercial construction
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	3,832	6,289
30 to 89 days past due	0	0
90 days past due and accruing	0	0
Nonaccrual	0	46
Total loans receivable	3,832	6,335
Land and land development loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	31,032	35,835
30 to 89 days past due	0	12
90 days past due and accruing	0	0
Nonaccrual	246	2,652
Total loans receivable	31,278	38,499
Agriculture
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	85,835	81,129
30 to 89 days past due	34	0
90 days past due and accruing	0	0
Nonaccrual	98	187
Total loans receivable	85,967	81,316
Multifamily
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	16,544	26,038
30 to 89 days past due	0	0
90 days past due and accruing	0	0
Nonaccrual	0	0
Total loans receivable	16,544	26,038
Residential real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	59,158	58,037
30 to 89 days past due	439	423
90 days past due and accruing	0	0
Nonaccrual	423	401
Total loans receivable	60,020	58,861
Residential construction
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	940	2,742
30 to 89 days past due	0	0
90 days past due and accruing	0	0
Nonaccrual	0	0
Total loans receivable	940	2,742
Consumer
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	9,577	11,739
30 to 89 days past due	45	91
90 days past due and accruing	0	0
Nonaccrual	4	17
Total loans receivable	9,626	11,847
Municipal
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	12,267	11,063
30 to 89 days past due	0	0
90 days past due and accruing	0	0
Nonaccrual	0	0
Total loans receivable	$ 12,267	$ 11,063