Loans, Loans Portfolio by Credit Quality Indicators (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012	Mar. 31, 2012
Financing Receivable, Recorded Investment [Line Items]
Total	$ 549,667	$ 453,783	$ 456,981
Commercial and Industrial [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	35,415	26,210
Commercial Secured By Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	282,844	230,028
Residential Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	214,484	183,370
Consumer [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	13,973	10,631
Agricultural [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	1,805	1,668
Other [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	1,146	1,876
Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	517,159	427,890
Pass [Member] | Commercial and Industrial [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	31,083	22,965
Pass [Member] | Commercial Secured By Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	262,682	218,246
Pass [Member] | Residential Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	206,546	172,589
Pass [Member] | Consumer [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	13,931	10,549
Pass [Member] | Agricultural [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	1,771	1,665
Pass [Member] | Other [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	1,146	1,876
OAEM [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	5,912	6,810
OAEM [Member] | Commercial and Industrial [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	1,793	1,804
OAEM [Member] | Commercial Secured By Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	1,797	2,653
OAEM [Member] | Residential Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	2,322	2,353
OAEM [Member] | Consumer [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	0	0
OAEM [Member] | Agricultural [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	0	0
OAEM [Member] | Other [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	0	0
Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	26,415	18,394
Substandard [Member] | Commercial and Industrial [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	2,358	1,177
Substandard [Member] | Commercial Secured By Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	18,365	9,022
Substandard [Member] | Residential Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	5,616	8,130
Substandard [Member] | Consumer [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	42	62
Substandard [Member] | Agricultural [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	34	3
Substandard [Member] | Other [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	0	0
Doubtful [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	181	689
Doubtful [Member] | Commercial and Industrial [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	181	264
Doubtful [Member] | Commercial Secured By Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	0	107
Doubtful [Member] | Residential Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	0	298
Doubtful [Member] | Consumer [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	0	20
Doubtful [Member] | Agricultural [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	0	0
Doubtful [Member] | Other [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	$ 0	$ 0