Credit Quality and Related Allowance for Loan Losses (Details 5) (USD $)	3 Months Ended		9 Months Ended			3 Months Ended		9 Months Ended			3 Months Ended		9 Months Ended			9 Months Ended		3 Months Ended		9 Months Ended			9 Months Ended		3 Months Ended		9 Months Ended			3 Months Ended		9 Months Ended			3 Months Ended		9 Months Ended
	Sep. 30, 2014 component class	Sep. 30, 2013	Sep. 30, 2014 quarter component class	Sep. 30, 2013	Dec. 31, 2013	Sep. 30, 2014 Commercial and agricultural	Sep. 30, 2013 Commercial and agricultural	Sep. 30, 2014 Commercial and agricultural	Sep. 30, 2013 Commercial and agricultural	Dec. 31, 2013 Commercial and agricultural	Sep. 30, 2014 Residential	Sep. 30, 2013 Residential	Sep. 30, 2014 Residential	Sep. 30, 2013 Residential	Dec. 31, 2013 Residential	Sep. 30, 2014 Residential Financing receivable Owners of rental properties	Sep. 30, 2013 Residential Financing receivable Owners of rental properties	Sep. 30, 2014 Commercial	Sep. 30, 2013 Commercial	Sep. 30, 2014 Commercial	Sep. 30, 2013 Commercial	Dec. 31, 2013 Commercial	Sep. 30, 2014 Commercial Financing receivable Owners of rental properties	Sep. 30, 2013 Commercial Financing receivable Owners of rental properties	Sep. 30, 2014 Construction	Sep. 30, 2013 Construction	Sep. 30, 2014 Construction	Sep. 30, 2013 Construction	Dec. 31, 2013 Construction	Sep. 30, 2014 Installment loans to individuals	Sep. 30, 2013 Installment loans to individuals	Sep. 30, 2014 Installment loans to individuals	Sep. 30, 2013 Installment loans to individuals	Dec. 31, 2013 Installment loans to individuals	Sep. 30, 2014 Unallocated	Sep. 30, 2013 Unallocated	Sep. 30, 2014 Unallocated	Sep. 30, 2013 Unallocated	Dec. 31, 2013 Unallocated	Sep. 30, 2014 Purchased loans	Jun. 01, 2013 Purchased loans
Loans and Leases Receivable Disclosure [Abstract]
The total number of components that represents the allowance for loan losses	2		2
The number of classes that groups of loans are collectively evaluated for impairment	2		2
Period considered for quarter moving average which is a factor to calculate historical charge-off			12
Activity in the allowance
Allowance for loan losses																																								$ 0	$ 0
Changes in allowance
Beginning Balance	8,811,000	9,404,000	10,144,000	7,617,000		694,000	540,000	474,000	361,000		3,262,000	3,045,000	3,917,000	1,954,000				3,394,000	3,988,000	4,079,000	3,831,000				718,000	843,000	741,000	950,000		198,000	141,000	139,000	144,000		545,000	847,000	794,000	377,000
Charge-offs	(38,000)	(427,000)	(2,207,000)	(617,000)		0	0	0	0		(2,000)	(105,000)	(65,000)	(239,000)				0	(193,000)	(2,038,000)	(199,000)				0	(100,000)	0	(100,000)		(36,000)	(29,000)	(104,000)	(79,000)		0	0	0	0
Recoveries	17,000	53,000	68,000	955,000		1,000	39,000	12,000	52,000		6,000	(2,000)	9,000	3,000				0	1,000	0	7,000				0	1,000	0	851,000		10,000	14,000	47,000	42,000		0	0	0	0
Provision for loan losses	460,000	600,000	1,245,000	1,675,000		133,000	(59,000)	342,000	107,000		157,000	520,000	(438,000)	1,740,000				283,000	(31,000)	1,636,000	126,000				67,000	8,000	44,000	(949,000)		64,000	14,000	154,000	33,000		(244,000)	148,000	(493,000)	618,000
Ending Balance	9,250,000	9,630,000	9,250,000	9,630,000		828,000	520,000	828,000	520,000		3,423,000	3,458,000	3,423,000	3,458,000				3,677,000	3,765,000	3,677,000	3,765,000				785,000	752,000	785,000	752,000		236,000	140,000	236,000	140,000		301,000	995,000	301,000	995,000
Concentration of loans (as a percent)																15.98%	15.73%						14.90%	13.20%
Allowance for Loan Losses:
Individually evaluated for impairment	1,480,000		1,480,000		2,555,000	150,000		150,000		224,000	80,000		80,000		65,000			1,079,000		1,079,000		2,153,000			171,000		171,000		113,000	0		0		0	0		0		0
Collectively evaluated for impairment	7,770,000		7,770,000		7,589,000	678,000		678,000		250,000	3,343,000		3,343,000		3,852,000			2,598,000		2,598,000		1,926,000			614,000		614,000		628,000	236,000		236,000		139,000	301,000		301,000		794,000
Total ending allowance balance	9,250,000	9,630,000	9,250,000	9,630,000		828,000	520,000	828,000	520,000		3,423,000	3,458,000	3,423,000	3,458,000				3,677,000	3,765,000	3,677,000	3,765,000				785,000	752,000	785,000	752,000		236,000	140,000	236,000	140,000		301,000	995,000	301,000	995,000
Loans:
Individually evaluated for impairment	14,086,000		14,086,000		10,160,000	1,136,000		1,136,000		532,000	1,005,000		1,005,000		881,000			10,630,000		10,630,000		7,707,000			1,315,000		1,315,000		1,040,000	0		0		0
Loans acquired with deteriorated credit quality	655,000		655,000		868,000	0		0		0	349,000		349,000		354,000			306,000		306,000		514,000			0		0		0	0		0								655,000
Collectively evaluated for impairment	877,268,000		877,268,000		808,187,000	123,143,000		123,143,000		104,497,000	434,120,000		434,120,000		398,546,000			278,447,000		278,447,000		274,255,000			20,839,000		20,839,000		16,242,000	20,719,000		20,719,000		14,647,000
Total	$ 892,009,000		$ 892,009,000		$ 819,215,000	$ 124,279,000		$ 124,279,000		$ 105,029,000	$ 435,474,000		$ 435,474,000		$ 399,781,000			$ 289,383,000		$ 289,383,000		$ 282,476,000			$ 22,154,000		$ 22,154,000		$ 17,282,000	$ 20,719,000		$ 20,719,000		$ 14,647,000