Loans (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Segments of loan portfolio and allowance for loan losses [Abstract]
Total Loans	$ 565,179		$ 554,105
Allowance for loan losses	6,922		6,815
Net loans	558,257		547,290
Individually evaluated for impairment	9,210		8,822
Collectively evaluated for impairment	555,969		545,283
Summary of allowance for loan losses into amount required for loans individually evaluated for impairment and the amount required for loans collectively evaluated for impairment [Abstract]
Individually evaluated for impairment	188		98
Collectively evaluated for impairment	6,734		6,717
Total	6,922	7,233
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance at beginning of period	6,815	7,098
Charge-offs	(25)	(56)
Recoveries	12	11
Provision	120	180
Balance at end of period	6,922	7,233
Minimum [Member]
Segments of loan portfolio and allowance for loan losses [Abstract]
Number of days past for loan to be considered impaired, Minimum	90 days
First Mortgage [Member] \| Minimum [Member]
Segments of loan portfolio and allowance for loan losses [Abstract]
Period of mortgage on real estate	15 years
First Mortgage [Member] \| Maximum [Member]
Segments of loan portfolio and allowance for loan losses [Abstract]
Period of mortgage on real estate	30 years
Second Mortgage [Member] \| Maximum [Member]
Segments of loan portfolio and allowance for loan losses [Abstract]
Period of mortgage on real estate	15 years
Residential [Member]
Segments of loan portfolio and allowance for loan losses [Abstract]
Total Loans	183,838		185,438
Individually evaluated for impairment	310		316
Collectively evaluated for impairment	183,528		185,122
Summary of allowance for loan losses into amount required for loans individually evaluated for impairment and the amount required for loans collectively evaluated for impairment [Abstract]
Individually evaluated for impairment	25		25
Collectively evaluated for impairment	898		853
Total	923	886
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance at beginning of period	878	946
Charge-offs	(17)	(38)
Recoveries	0	0
Provision	62	(22)
Balance at end of period	923	886
Commercial and Agricultural [Member]
Segments of loan portfolio and allowance for loan losses [Abstract]
Total Loans	218,392		215,584
Individually evaluated for impairment	6,010		6,112
Collectively evaluated for impairment	212,382		209,472
Summary of allowance for loan losses into amount required for loans individually evaluated for impairment and the amount required for loans collectively evaluated for impairment [Abstract]
Individually evaluated for impairment	72		72
Collectively evaluated for impairment	3,627		3,798
Total	3,699	4,530
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance at beginning of period	3,870	4,558
Charge-offs	0	(10)
Recoveries	4	2
Provision	(175)	(20)
Balance at end of period	3,699	4,530
Construction [Member]
Segments of loan portfolio and allowance for loan losses [Abstract]
Total Loans	6,036		6,353
Individually evaluated for impairment	0		0
Collectively evaluated for impairment	6,036		6,353
Summary of allowance for loan losses into amount required for loans individually evaluated for impairment and the amount required for loans collectively evaluated for impairment [Abstract]
Individually evaluated for impairment	0		0
Collectively evaluated for impairment	11		26
Total	11	8
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance at beginning of period	26	50
Charge-offs	0	0
Recoveries	0	0
Provision	(15)	(42)
Balance at end of period	11	8
Home Equity [Member]
Segments of loan portfolio and allowance for loan losses [Abstract]
Total Loans	60,727		62,580
Commercial [Member]
Segments of loan portfolio and allowance for loan losses [Abstract]
Total Loans	192,701		190,945
Agricultural [Member]
Segments of loan portfolio and allowance for loan losses [Abstract]
Total Loans	25,691		24,639
Consumer [Member]
Segments of loan portfolio and allowance for loan losses [Abstract]
Total Loans	8,171		8,497
Individually evaluated for impairment	0		0
Collectively evaluated for impairment	8,171		8,497
Summary of allowance for loan losses into amount required for loans individually evaluated for impairment and the amount required for loans collectively evaluated for impairment [Abstract]
Individually evaluated for impairment	0		0
Collectively evaluated for impairment	82		84
Total	82	83
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance at beginning of period	84	105
Charge-offs	(7)	(8)
Recoveries	8	9
Provision	(3)	(23)
Balance at end of period	82	83
Other Commercial and Agricultural Loans [Member]
Segments of loan portfolio and allowance for loan losses [Abstract]
Total Loans	63,386		58,516
Individually evaluated for impairment	2,890		2,394
Collectively evaluated for impairment	60,496		56,122
Summary of allowance for loan losses into amount required for loans individually evaluated for impairment and the amount required for loans collectively evaluated for impairment [Abstract]
Individually evaluated for impairment	91		1
Collectively evaluated for impairment	1,195		1,223
Total	1,286	1,173
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance at beginning of period	1,224	942
Charge-offs	(1)	0
Recoveries	0	0
Provision	63	231
Balance at end of period	1,286	1,173
Other Agricultural Loans [Member]
Segments of loan portfolio and allowance for loan losses [Abstract]
Total Loans	10,780		11,065
State and Political Subdivision Loans [Member]
Segments of loan portfolio and allowance for loan losses [Abstract]
Total Loans	85,356		79,717
Individually evaluated for impairment	0		0
Collectively evaluated for impairment	85,356		79,717
Summary of allowance for loan losses into amount required for loans individually evaluated for impairment and the amount required for loans collectively evaluated for impairment [Abstract]
Individually evaluated for impairment	0		0
Collectively evaluated for impairment	572		545
Total	572	396
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance at beginning of period	545	330
Charge-offs	0	0
Recoveries	0	0
Provision	27	66
Balance at end of period	572	396
Residential Mortgages [Member]
Segments of loan portfolio and allowance for loan losses [Abstract]
Total Loans	123,111		122,858
Unallocated [Member]
Summary of allowance for loan losses into amount required for loans individually evaluated for impairment and the amount required for loans collectively evaluated for impairment [Abstract]
Individually evaluated for impairment	0		0
Collectively evaluated for impairment	349		188
Total	349	157
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance at beginning of period	188	167
Charge-offs	0	0
Recoveries	0	0
Provision	161	(10)
Balance at end of period	$ 349	$ 157

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A valuation allowance for financing receivables that are expected to be uncollectible.

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The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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Amount of recovery of financing receivables doubtful of collection that were previously charged off.

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Amount of direct write-downs of financing receivables charged against the allowance.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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