Loans (Details 4) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Loans receivable, commercial credit exposure	$ 344,933	$ 331,630
High quality (risk rating 1)
Loans receivable, commercial credit exposure	38	65
Minimal (risk rating 2)
Loans receivable, commercial credit exposure	38,992	34,725
Average (risk rating 3)
Loans receivable, commercial credit exposure	193,759	178,223
Acceptable (risk rating 4)
Loans receivable, commercial credit exposure	81,235	83,524
Watch (risk rating 5)
Loans receivable, commercial credit exposure	18,319	17,929
Substandard (risk rating 6)
Loans receivable, commercial credit exposure	3,123	2,617
Impaired loans (risk rating 7)
Loans receivable, commercial credit exposure	9,467	14,547
Commercial Loan
Loans receivable, commercial credit exposure	114,243	117,422
Commercial Loan | High quality (risk rating 1)
Loans receivable, commercial credit exposure	38	65
Commercial Loan | Minimal (risk rating 2)
Loans receivable, commercial credit exposure	16,360	10,404
Commercial Loan | Average (risk rating 3)
Loans receivable, commercial credit exposure	51,846	54,387
Commercial Loan | Acceptable (risk rating 4)
Loans receivable, commercial credit exposure	32,002	38,381
Commercial Loan | Watch (risk rating 5)
Loans receivable, commercial credit exposure	8,271	7,054
Commercial Loan | Substandard (risk rating 6)
Loans receivable, commercial credit exposure	617	675
Commercial Loan | Impaired loans (risk rating 7)
Loans receivable, commercial credit exposure	5,109	6,456
Commercial Real Estate
Loans receivable, commercial credit exposure	183,818	184,360
Commercial Real Estate | High quality (risk rating 1)
Loans receivable, commercial credit exposure
Commercial Real Estate | Minimal (risk rating 2)
Loans receivable, commercial credit exposure	20,193	21,922
Commercial Real Estate | Average (risk rating 3)
Loans receivable, commercial credit exposure	103,454	103,614
Commercial Real Estate | Acceptable (risk rating 4)
Loans receivable, commercial credit exposure	45,699	42,435
Commercial Real Estate | Watch (risk rating 5)
Loans receivable, commercial credit exposure	8,291	7,972
Commercial Real Estate | Substandard (risk rating 6)
Loans receivable, commercial credit exposure	2,179	1,005
Commercial Real Estate | Impaired loans (risk rating 7)
Loans receivable, commercial credit exposure	4,002	7,412
Construction and Development
Loans receivable, commercial credit exposure	28,482	20,078
Construction and Development | High quality (risk rating 1)
Loans receivable, commercial credit exposure
Construction and Development | Minimal (risk rating 2)
Loans receivable, commercial credit exposure	305	205
Construction and Development | Average (risk rating 3)
Loans receivable, commercial credit exposure	22,573	12,981
Construction and Development | Acceptable (risk rating 4)
Loans receivable, commercial credit exposure	3,318	2,401
Construction and Development | Watch (risk rating 5)
Loans receivable, commercial credit exposure	1,757	2,903
Construction and Development | Substandard (risk rating 6)
Loans receivable, commercial credit exposure	327	937
Construction and Development | Impaired loans (risk rating 7)
Loans receivable, commercial credit exposure	202	651
Agricultural
Loans receivable, commercial credit exposure	4,265	1,957
Agricultural | High quality (risk rating 1)
Loans receivable, commercial credit exposure
Agricultural | Minimal (risk rating 2)
Loans receivable, commercial credit exposure	559	534
Agricultural | Average (risk rating 3)
Loans receivable, commercial credit exposure	3,336	1,088
Agricultural | Acceptable (risk rating 4)
Loans receivable, commercial credit exposure	216	307
Agricultural | Watch (risk rating 5)
Loans receivable, commercial credit exposure
Agricultural | Substandard (risk rating 6)
Loans receivable, commercial credit exposure
Agricultural | Impaired loans (risk rating 7)
Loans receivable, commercial credit exposure	154	28
Government
Loans receivable, commercial credit exposure	14,125	7,813
Government | High quality (risk rating 1)
Loans receivable, commercial credit exposure
Government | Minimal (risk rating 2)
Loans receivable, commercial credit exposure	1,575	1,660
Government | Average (risk rating 3)
Loans receivable, commercial credit exposure	12,550	6,153
Government | Acceptable (risk rating 4)
Loans receivable, commercial credit exposure
Government | Watch (risk rating 5)
Loans receivable, commercial credit exposure
Government | Substandard (risk rating 6)
Loans receivable, commercial credit exposure
Government | Impaired loans (risk rating 7)
Loans receivable, commercial credit exposure