Credit Quality and Related Allowance for Loan Losses (Details 4) (USD $)	9 Months Ended
	Sep. 30, 2014 category	Dec. 31, 2013
Loans and Leases Receivable Disclosure [Abstract]
Number of categories considered not criticized and rated as "Pass"	6
Minimum period after which loans are considered as substandard	90 days
Minimum amount after which external annual loan review is performed	$ 800,000
Credit quality categories
Total	892,009,000	819,215,000
Commercial and agricultural
Credit quality categories
Total	124,279,000	105,029,000
Residential
Credit quality categories
Total	435,474,000	399,781,000
Commercial
Credit quality categories
Total	289,383,000	282,476,000
Construction
Credit quality categories
Total	22,154,000	17,282,000
Installment loans to individuals
Credit quality categories
Total	20,719,000	14,647,000
Pass
Credit quality categories
Total	859,246,000	785,343,000
Pass | Commercial and agricultural
Credit quality categories
Total	116,755,000	99,256,000
Pass | Residential
Credit quality categories
Total	433,579,000	398,327,000
Pass | Commercial
Credit quality categories
Total	266,751,000	259,505,000
Pass | Construction
Credit quality categories
Total	21,442,000	13,608,000
Pass | Installment loans to individuals
Credit quality categories
Total	20,719,000	14,647,000
Special Mention
Credit quality categories
Total	15,606,000	15,522,000
Special Mention | Commercial and agricultural
Credit quality categories
Total	6,240,000	4,529,000
Special Mention | Residential
Credit quality categories
Total	1,476,000	598,000
Special Mention | Commercial
Credit quality categories
Total	7,674,000	10,181,000
Special Mention | Construction
Credit quality categories
Total	216,000	214,000
Special Mention | Installment loans to individuals
Credit quality categories
Total	0	0
Substandard
Credit quality categories
Total	17,157,000	18,350,000
Substandard | Commercial and agricultural
Credit quality categories
Total	1,284,000	1,244,000
Substandard | Residential
Credit quality categories
Total	419,000	856,000
Substandard | Commercial
Credit quality categories
Total	14,958,000	12,790,000
Substandard | Construction
Credit quality categories
Total	496,000	3,460,000
Substandard | Installment loans to individuals
Credit quality categories
Total	$ 0	$ 0