Fair Value Measurements (Details) (USD $) In Thousands, unless otherwise specified				3 Months Ended
	Mar. 31, 2014	Dec. 31, 2013	Mar. 31, 2013	Mar. 31, 2014 Residential 1st Mortgages [Member] Sales Comparison Approach [Member]	Mar. 31, 2014 Residential 1st Mortgages [Member] Minimum [Member] Sales Comparison Approach [Member]	Mar. 31, 2014 Residential 1st Mortgages [Member] Maximum [Member] Sales Comparison Approach [Member]	Mar. 31, 2014 Residential 1st Mortgages [Member] Weighted Average [Member] Sales Comparison Approach [Member]	Mar. 31, 2014 Home Equity Lines and Loans [Member] Sales Comparison Approach [Member]	Mar. 31, 2014 Home Equity Lines and Loans [Member] Minimum [Member] Sales Comparison Approach [Member]	Mar. 31, 2014 Home Equity Lines and Loans [Member] Maximum [Member] Sales Comparison Approach [Member]	Mar. 31, 2014 Home Equity Lines and Loans [Member] Weighted Average [Member] Sales Comparison Approach [Member]	Mar. 31, 2014 Agricultural [Member] Income Approach [Member]	Mar. 31, 2014 Agricultural [Member] Minimum [Member] Income Approach [Member]	Mar. 31, 2014 Agricultural [Member] Maximum [Member] Income Approach [Member]	Mar. 31, 2014 Agricultural [Member] Weighted Average [Member] Income Approach [Member]	Mar. 31, 2014 Commercial [Member] Sales Comparison Approach [Member]	Mar. 31, 2014 Commercial [Member] Minimum [Member] Sales Comparison Approach [Member]	Mar. 31, 2014 Commercial [Member] Maximum [Member] Sales Comparison Approach [Member]	Mar. 31, 2014 Commercial [Member] Weighted Average [Member] Sales Comparison Approach [Member]	Mar. 31, 2014 Real Estate Construction [Member] Sales Comparison Approach [Member]	Mar. 31, 2014 Real Estate Construction [Member] Minimum [Member] Sales Comparison Approach [Member]	Mar. 31, 2014 Real Estate Construction [Member] Maximum [Member] Sales Comparison Approach [Member]	Mar. 31, 2014 Real Estate Construction [Member] Weighted Average [Member] Sales Comparison Approach [Member]	Mar. 31, 2014 Agricultural Real Estate [Member] Sales Comparison Approach [Member]	Mar. 31, 2014 Agricultural Real Estate [Member] Minimum [Member] Sales Comparison Approach [Member]	Mar. 31, 2014 Agricultural Real Estate [Member] Maximum [Member] Sales Comparison Approach [Member]	Mar. 31, 2014 Agricultural Real Estate [Member] Weighted Average [Member] Sales Comparison Approach [Member]	Mar. 31, 2014 Recurring [Member]	Dec. 31, 2013 Recurring [Member]	Mar. 31, 2013 Recurring [Member]	Mar. 31, 2014 Recurring [Member] Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]	Dec. 31, 2013 Recurring [Member] Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]	Mar. 31, 2013 Recurring [Member] Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]	Mar. 31, 2014 Recurring [Member] Other Observable Inputs (Level 2) [Member]	Dec. 31, 2013 Recurring [Member] Other Observable Inputs (Level 2) [Member]	Mar. 31, 2013 Recurring [Member] Other Observable Inputs (Level 2) [Member]	Mar. 31, 2014 Recurring [Member] Significant Unobservable Inputs (Level 3) [Member]	Dec. 31, 2013 Recurring [Member] Significant Unobservable Inputs (Level 3) [Member]	Mar. 31, 2013 Recurring [Member] Significant Unobservable Inputs (Level 3) [Member]	Mar. 31, 2014 Nonrecurring [Member]	Dec. 31, 2013 Nonrecurring [Member]	Mar. 31, 2013 Nonrecurring [Member]	Mar. 31, 2014 Nonrecurring [Member] Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]	Dec. 31, 2013 Nonrecurring [Member] Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]	Mar. 31, 2013 Nonrecurring [Member] Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]	Mar. 31, 2014 Nonrecurring [Member] Other Observable Inputs (Level 2) [Member]	Dec. 31, 2013 Nonrecurring [Member] Other Observable Inputs (Level 2) [Member]	Mar. 31, 2013 Nonrecurring [Member] Other Observable Inputs (Level 2) [Member]	Mar. 31, 2014 Nonrecurring [Member] Significant Unobservable Inputs (Level 3) [Member]	Dec. 31, 2013 Nonrecurring [Member] Significant Unobservable Inputs (Level 3) [Member]	Mar. 31, 2013 Nonrecurring [Member] Significant Unobservable Inputs (Level 3) [Member]
Available-for-Sale Securities [Abstract]
Government Agency & Government-Sponsored Entities																												$ 18,426	$ 28,436	$ 26,692	$ 13,399	$ 23,394	$ 21,612	$ 5,027	$ 5,042	$ 5,080	$ 0	$ 0	$ 0
Obligations of States and Political Subdivisions																														5,643			0			0			5,643
Mortgage Backed Securities																												329,730	324,929	432,285	0	0	0	329,730	324,929	432,285	0	0	0
Corporate Securities																												49,352	49,380	50,128	7,966	8,191	9,373	41,386	41,189	40,755	0	0	0
Other																												2,235	1,894	825	1,925	1,584	515	310	310	310	0	0	0
Fair/Book Value, Total	399,743	404,639	515,573																									399,743	404,639	515,573	23,290	33,169	31,500	376,453	371,470	478,430	0	0	5,643
Impaired Loans [Abstract]
Agriculture Real Estate																																										1,572			0			0			1,572
Residential 1st Mortgage																																								329	614	289	0	0	0	0	0	0	329	614	289
Home Equity Lines and Loans																																								273	551	15	0	0	0	0	0	0	273	551	15
Agricultural																																								354	366	965	0	0	0	0	0	0	354	366	965
Commercial																																								814	820	220	0	0	0	0	0	0	814	820	220
Total Impaired Loans																																								1,770	2,351	3,061	0	0	0	0	0	0	1,770	2,351	3,061
Other Real Estate [Abstract]
Real Estate Construction																																								2,441	2,399	2,553	0	0	0	0	0	0	2,441	2,399	2,553
Agricultural Real Estate																																								853	2,212	1,910	0	0	0	0	0	0	853	2,212	1,910
Agricultural																																										280			0			0			280
Total Other Real Estate																																								3,294	4,611	4,743	0	0	0	0	0	0	3,294	4,611	4,743
Total Assets Measured at Fair Value On a Non-Recurring Basis				329				273				354				814				2,441				853																5,064	6,962	7,804	0	0	0	0	0	0	5,064	6,962	7,804
Quantitative Information [Abstract]
Fair Value				$ 329				$ 273				$ 354				$ 814				$ 2,441				$ 853																$ 5,064	$ 6,962	$ 7,804	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0	$ 5,064	$ 6,962	$ 7,804
Valuation Technique				Sales Comparison Approach				Sales Comparison Approach				Income Approach				Sales Comparison Approach				Sales Comparison Approach				Sales Comparison Approach
Unobservable Inputs				Adjustment for Difference Between Comparable Sales				Adjustment for Difference Between Comparable Sales				Capitalization Rate				Adjustment for Difference Between Comparable Sales				Adjustment for Difference Between Comparable Sales				Adjustment for Difference Between Comparable Sales
Range, Weighted Avg. (in hundredths)					10.00%	19.00%	14.00%		2.00%	15.00%	7.00%		14.00%	14.00%	14.00%		13.00%	13.00%	13.00%		10.00%	10.00%	10.00%		10.00%	10.00%	10.00%