Credit Quality and Related Allowance for Loan Losses (Details 4) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 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
Credit quality categories
Total	821,520	819,215
Commercial and agricultural
Credit quality categories
Total	108,314	105,029
Residential
Credit quality categories
Total	403,294	399,781
Commercial
Credit quality categories
Total	275,806	282,476
Construction
Credit quality categories
Total	16,004	17,282
Installment loans to individuals
Credit quality categories
Total	18,102	14,647
Pass
Credit quality categories
Total	792,202	785,343
Pass | Commercial and agricultural
Credit quality categories
Total	101,785	99,256
Pass | Residential
Credit quality categories
Total	401,898	398,327
Pass | Commercial
Credit quality categories
Total	255,639	259,505
Pass | Construction
Credit quality categories
Total	14,779	13,608
Pass | Installment loans to individuals
Credit quality categories
Total	18,101	14,647
Special Mention
Credit quality categories
Total	15,596	15,522
Special Mention | Commercial and agricultural
Credit quality categories
Total	5,299	4,529
Special Mention | Residential
Credit quality categories
Total	603	598
Special Mention | Commercial
Credit quality categories
Total	9,487	10,181
Special Mention | Construction
Credit quality categories
Total	207	214
Special Mention | Installment loans to individuals
Credit quality categories
Total	0	0
Substandard
Credit quality categories
Total	13,722	18,350
Substandard | Commercial and agricultural
Credit quality categories
Total	1,230	1,244
Substandard | Residential
Credit quality categories
Total	793	856
Substandard | Commercial
Credit quality categories
Total	10,680	12,790
Substandard | Construction
Credit quality categories
Total	1,018	3,460
Substandard | Installment loans to individuals
Credit quality categories
Total	$ 1	$ 0