Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands		Dec. 31, 2016	Dec. 31, 2015
Assets [Abstract]
Available-for-Sale Securities		$ 448,263	$ 369,137
Investment Securities Held-to-Maturity		58,408	62,388
Obligations of States and Political Subdivisions [Member]
Assets [Abstract]
Investment Securities Held-to-Maturity		58,408	62,388
Government Agency & Government-Sponsored Entities [Member]
Assets [Abstract]
Available-for-Sale Securities		3,241	33,251
US Govt SBA [Member]
Assets [Abstract]
Available-for-Sale Securities		36,314
US Treasury Notes [Member]
Assets [Abstract]
Available-for-Sale Securities		134,428	72,884
Mortgage Backed Securities [Member]
Assets [Abstract]
Available-for-Sale Securities	[1]	273,270	262,493
Other [Member]
Assets [Abstract]
Available-for-Sale Securities		1,010	509
Carrying Amount [Member]
Assets [Abstract]
Cash and Cash Equivalents		98,960	59,446
Available-for-Sale Securities		448,263	369,137
Investment Securities Held-to-Maturity		58,109	61,396
FHLB Stock		8,872	7,795
Loans & Leases, Net of Deferred Fees & Allowance		2,129,682	1,954,836
Accrued Interest Receivable		10,047	9,240
Liabilities [Abstract]
Deposits		2,581,711	2,277,532
Subordinated Debentures		10,310	10,310
Accrued Interest Payable		852	513
Carrying Amount [Member] | Demand [Member]
Liabilities [Abstract]
Deposits		756,236	711,029
Carrying Amount [Member] | Interest Bearing Transaction [Member]
Liabilities [Abstract]
Deposits		495,063	377,594
Carrying Amount [Member] | Savings and Money Market [Member]
Liabilities [Abstract]
Deposits		760,119	707,885
Carrying Amount [Member] | Time [Member]
Liabilities [Abstract]
Deposits		570,293	481,024
Carrying Amount [Member] | Commercial Real Estate [Member]
Assets [Abstract]
Loans & Leases, Net of Deferred Fees & Allowance		656,936	593,587
Carrying Amount [Member] | Agricultural Real Estate [Member]
Assets [Abstract]
Loans & Leases, Net of Deferred Fees & Allowance		458,235	417,153
Carrying Amount [Member] | Real Estate Construction [Member]
Assets [Abstract]
Loans & Leases, Net of Deferred Fees & Allowance		173,239	149,489
Carrying Amount [Member] | Residential 1st Mortgages [Member]
Assets [Abstract]
Loans & Leases, Net of Deferred Fees & Allowance		241,382	205,616
Carrying Amount [Member] | Home Equity Lines and Loans [Member]
Assets [Abstract]
Loans & Leases, Net of Deferred Fees & Allowance		29,485	30,910
Carrying Amount [Member] | Agricultural [Member]
Assets [Abstract]
Loans & Leases, Net of Deferred Fees & Allowance		287,944	287,658
Carrying Amount [Member] | Commercial [Member]
Assets [Abstract]
Loans & Leases, Net of Deferred Fees & Allowance		209,062	202,968
Carrying Amount [Member] | Consumer & Other [Member]
Assets [Abstract]
Loans & Leases, Net of Deferred Fees & Allowance		6,713	6,417
Carrying Amount [Member] | Leases [Member]
Assets [Abstract]
Loans & Leases, Net of Deferred Fees & Allowance		68,135	62,584
Carrying Amount [Member] | Unallocated [Member]
Assets [Abstract]
Loans & Leases, Net of Deferred Fees & Allowance		(1,449)	(1,546)
Carrying Amount [Member] | Obligations of States and Political Subdivisions [Member]
Assets [Abstract]
Investment Securities Held-to-Maturity		58,109	61,396
Carrying Amount [Member] | Government Agency & Government-Sponsored Entities [Member]
Assets [Abstract]
Available-for-Sale Securities		3,241	33,251
Carrying Amount [Member] | US Govt SBA [Member]
Assets [Abstract]
Available-for-Sale Securities		36,314
Carrying Amount [Member] | US Treasury Notes [Member]
Assets [Abstract]
Available-for-Sale Securities		134,428	72,884
Carrying Amount [Member] | Mortgage Backed Securities [Member]
Assets [Abstract]
Available-for-Sale Securities		273,270	262,493
Carrying Amount [Member] | Other [Member]
Assets [Abstract]
Available-for-Sale Securities		1,010	509
Estimated Fair Value [Member]
Assets [Abstract]
Cash and Cash Equivalents		98,960	59,446
Available-for-Sale Securities		448,263	369,137
Investment Securities Held-to-Maturity		58,408	62,388
Loans & Leases, Net of Deferred Fees & Allowance		2,107,060	1,939,575
Accrued Interest Receivable		10,047	9,240
Liabilities [Abstract]
Deposits		2,580,601	2,276,842
Subordinated Debentures		6,578	6,424
Accrued Interest Payable		852	513
Estimated Fair Value [Member] | Demand [Member]
Liabilities [Abstract]
Deposits		756,236	711,029
Estimated Fair Value [Member] | Interest Bearing Transaction [Member]
Liabilities [Abstract]
Deposits		495,063	377,594
Estimated Fair Value [Member] | Savings and Money Market [Member]
Liabilities [Abstract]
Deposits		760,119	707,885
Estimated Fair Value [Member] | Time [Member]
Liabilities [Abstract]
Deposits		569,183	480,334
Estimated Fair Value [Member] | Commercial Real Estate [Member]
Assets [Abstract]
Loans & Leases, Net of Deferred Fees & Allowance		651,877	591,271
Estimated Fair Value [Member] | Agricultural Real Estate [Member]
Assets [Abstract]
Loans & Leases, Net of Deferred Fees & Allowance		444,393	405,295
Estimated Fair Value [Member] | Real Estate Construction [Member]
Assets [Abstract]
Loans & Leases, Net of Deferred Fees & Allowance		172,682	149,371
Estimated Fair Value [Member] | Residential 1st Mortgages [Member]
Assets [Abstract]
Loans & Leases, Net of Deferred Fees & Allowance		241,174	207,431
Estimated Fair Value [Member] | Home Equity Lines and Loans [Member]
Assets [Abstract]
Loans & Leases, Net of Deferred Fees & Allowance		30,495	32,360
Estimated Fair Value [Member] | Agricultural [Member]
Assets [Abstract]
Loans & Leases, Net of Deferred Fees & Allowance		286,074	285,733
Estimated Fair Value [Member] | Commercial [Member]
Assets [Abstract]
Loans & Leases, Net of Deferred Fees & Allowance		207,215	201,105
Estimated Fair Value [Member] | Consumer & Other [Member]
Assets [Abstract]
Loans & Leases, Net of Deferred Fees & Allowance		6,706	6,416
Estimated Fair Value [Member] | Leases [Member]
Assets [Abstract]
Loans & Leases, Net of Deferred Fees & Allowance		67,893	62,139
Estimated Fair Value [Member] | Unallocated [Member]
Assets [Abstract]
Loans & Leases, Net of Deferred Fees & Allowance		(1,449)	(1,546)
Estimated Fair Value [Member] | Obligations of States and Political Subdivisions [Member]
Assets [Abstract]
Investment Securities Held-to-Maturity		58,408	62,388
Estimated Fair Value [Member] | Government Agency & Government-Sponsored Entities [Member]
Assets [Abstract]
Available-for-Sale Securities		3,241	33,251
Estimated Fair Value [Member] | US Govt SBA [Member]
Assets [Abstract]
Available-for-Sale Securities		36,314
Estimated Fair Value [Member] | US Treasury Notes [Member]
Assets [Abstract]
Available-for-Sale Securities		134,428	72,884
Estimated Fair Value [Member] | Mortgage Backed Securities [Member]
Assets [Abstract]
Available-for-Sale Securities		273,270	262,493
Estimated Fair Value [Member] | Other [Member]
Assets [Abstract]
Available-for-Sale Securities		1,010	509
Estimated Fair Value [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Assets [Abstract]
Cash and Cash Equivalents		98,960	59,446
Available-for-Sale Securities		134,628	73,083
Investment Securities Held-to-Maturity		0	0
Loans & Leases, Net of Deferred Fees & Allowance		0	0
Accrued Interest Receivable		0	0
Liabilities [Abstract]
Deposits		2,011,418	1,796,508
Subordinated Debentures		0	0
Accrued Interest Payable		0	0
Estimated Fair Value [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Demand [Member]
Liabilities [Abstract]
Deposits		756,236	711,029
Estimated Fair Value [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Interest Bearing Transaction [Member]
Liabilities [Abstract]
Deposits		495,063	377,594
Estimated Fair Value [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Savings and Money Market [Member]
Liabilities [Abstract]
Deposits		760,119	707,885
Estimated Fair Value [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Time [Member]
Liabilities [Abstract]
Deposits		0	0
Estimated Fair Value [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Commercial Real Estate [Member]
Assets [Abstract]
Loans & Leases, Net of Deferred Fees & Allowance		0	0
Estimated Fair Value [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Agricultural Real Estate [Member]
Assets [Abstract]
Loans & Leases, Net of Deferred Fees & Allowance		0	0
Estimated Fair Value [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Real Estate Construction [Member]
Assets [Abstract]
Loans & Leases, Net of Deferred Fees & Allowance		0	0
Estimated Fair Value [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Residential 1st Mortgages [Member]
Assets [Abstract]
Loans & Leases, Net of Deferred Fees & Allowance		0	0
Estimated Fair Value [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Home Equity Lines and Loans [Member]
Assets [Abstract]
Loans & Leases, Net of Deferred Fees & Allowance		0	0
Estimated Fair Value [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Agricultural [Member]
Assets [Abstract]
Loans & Leases, Net of Deferred Fees & Allowance		0	0
Estimated Fair Value [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Commercial [Member]
Assets [Abstract]
Loans & Leases, Net of Deferred Fees & Allowance		0	0
Estimated Fair Value [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Consumer & Other [Member]
Assets [Abstract]
Loans & Leases, Net of Deferred Fees & Allowance		0	0
Estimated Fair Value [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Leases [Member]
Assets [Abstract]
Loans & Leases, Net of Deferred Fees & Allowance		0	0
Estimated Fair Value [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Unallocated [Member]
Assets [Abstract]
Loans & Leases, Net of Deferred Fees & Allowance		0	0
Estimated Fair Value [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Obligations of States and Political Subdivisions [Member]
Assets [Abstract]
Investment Securities Held-to-Maturity		0	0
Estimated Fair Value [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Government Agency & Government-Sponsored Entities [Member]
Assets [Abstract]
Available-for-Sale Securities		0	0
Estimated Fair Value [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | US Govt SBA [Member]
Assets [Abstract]
Available-for-Sale Securities		0
Estimated Fair Value [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | US Treasury Notes [Member]
Assets [Abstract]
Available-for-Sale Securities		134,428	72,884
Estimated Fair Value [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Mortgage Backed Securities [Member]
Assets [Abstract]
Available-for-Sale Securities		0	0
Estimated Fair Value [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Other [Member]
Assets [Abstract]
Available-for-Sale Securities		200	199
Estimated Fair Value [Member] | Other Observable Inputs (Level 2) [Member]
Assets [Abstract]
Cash and Cash Equivalents		0	0
Available-for-Sale Securities		313,135	296,054
Investment Securities Held-to-Maturity		40,415	44,675
Loans & Leases, Net of Deferred Fees & Allowance		0	0
Accrued Interest Receivable		10,047	9,240
Liabilities [Abstract]
Deposits		569,183	480,334
Subordinated Debentures		6,578	6,424
Accrued Interest Payable		852	513
Estimated Fair Value [Member] | Other Observable Inputs (Level 2) [Member] | Demand [Member]
Liabilities [Abstract]
Deposits		0	0
Estimated Fair Value [Member] | Other Observable Inputs (Level 2) [Member] | Interest Bearing Transaction [Member]
Liabilities [Abstract]
Deposits		0	0
Estimated Fair Value [Member] | Other Observable Inputs (Level 2) [Member] | Savings and Money Market [Member]
Liabilities [Abstract]
Deposits		0	0
Estimated Fair Value [Member] | Other Observable Inputs (Level 2) [Member] | Time [Member]
Liabilities [Abstract]
Deposits		569,183	480,334
Estimated Fair Value [Member] | Other Observable Inputs (Level 2) [Member] | Commercial Real Estate [Member]
Assets [Abstract]
Loans & Leases, Net of Deferred Fees & Allowance		0	0
Estimated Fair Value [Member] | Other Observable Inputs (Level 2) [Member] | Agricultural Real Estate [Member]
Assets [Abstract]
Loans & Leases, Net of Deferred Fees & Allowance		0	0
Estimated Fair Value [Member] | Other Observable Inputs (Level 2) [Member] | Real Estate Construction [Member]
Assets [Abstract]
Loans & Leases, Net of Deferred Fees & Allowance		0	0
Estimated Fair Value [Member] | Other Observable Inputs (Level 2) [Member] | Residential 1st Mortgages [Member]
Assets [Abstract]
Loans & Leases, Net of Deferred Fees & Allowance		0	0
Estimated Fair Value [Member] | Other Observable Inputs (Level 2) [Member] | Home Equity Lines and Loans [Member]
Assets [Abstract]
Loans & Leases, Net of Deferred Fees & Allowance		0	0
Estimated Fair Value [Member] | Other Observable Inputs (Level 2) [Member] | Agricultural [Member]
Assets [Abstract]
Loans & Leases, Net of Deferred Fees & Allowance		0	0
Estimated Fair Value [Member] | Other Observable Inputs (Level 2) [Member] | Commercial [Member]
Assets [Abstract]
Loans & Leases, Net of Deferred Fees & Allowance		0	0
Estimated Fair Value [Member] | Other Observable Inputs (Level 2) [Member] | Consumer & Other [Member]
Assets [Abstract]
Loans & Leases, Net of Deferred Fees & Allowance		0	0
Estimated Fair Value [Member] | Other Observable Inputs (Level 2) [Member] | Leases [Member]
Assets [Abstract]
Loans & Leases, Net of Deferred Fees & Allowance		0	0
Estimated Fair Value [Member] | Other Observable Inputs (Level 2) [Member] | Unallocated [Member]
Assets [Abstract]
Loans & Leases, Net of Deferred Fees & Allowance		0	0
Estimated Fair Value [Member] | Other Observable Inputs (Level 2) [Member] | Obligations of States and Political Subdivisions [Member]
Assets [Abstract]
Investment Securities Held-to-Maturity		40,415	44,675
Estimated Fair Value [Member] | Other Observable Inputs (Level 2) [Member] | Government Agency & Government-Sponsored Entities [Member]
Assets [Abstract]
Available-for-Sale Securities		3,241	33,251
Estimated Fair Value [Member] | Other Observable Inputs (Level 2) [Member] | US Govt SBA [Member]
Assets [Abstract]
Available-for-Sale Securities		36,314
Estimated Fair Value [Member] | Other Observable Inputs (Level 2) [Member] | US Treasury Notes [Member]
Assets [Abstract]
Available-for-Sale Securities		0	0
Estimated Fair Value [Member] | Other Observable Inputs (Level 2) [Member] | Mortgage Backed Securities [Member]
Assets [Abstract]
Available-for-Sale Securities		273,270	262,493
Estimated Fair Value [Member] | Other Observable Inputs (Level 2) [Member] | Other [Member]
Assets [Abstract]
Available-for-Sale Securities		310	310
Estimated Fair Value [Member] | Significant Unobservable Inputs (Level 3) [Member]
Assets [Abstract]
Cash and Cash Equivalents		0	0
Available-for-Sale Securities		500	0
Investment Securities Held-to-Maturity		17,993	17,713
Loans & Leases, Net of Deferred Fees & Allowance		2,107,060	1,939,575
Accrued Interest Receivable		0	0
Liabilities [Abstract]
Deposits		0	0
Subordinated Debentures		0	0
Accrued Interest Payable		0	0
Estimated Fair Value [Member] | Significant Unobservable Inputs (Level 3) [Member] | Demand [Member]
Liabilities [Abstract]
Deposits		0	0
Estimated Fair Value [Member] | Significant Unobservable Inputs (Level 3) [Member] | Interest Bearing Transaction [Member]
Liabilities [Abstract]
Deposits		0	0
Estimated Fair Value [Member] | Significant Unobservable Inputs (Level 3) [Member] | Savings and Money Market [Member]
Liabilities [Abstract]
Deposits		0	0
Estimated Fair Value [Member] | Significant Unobservable Inputs (Level 3) [Member] | Time [Member]
Liabilities [Abstract]
Deposits		0	0
Estimated Fair Value [Member] | Significant Unobservable Inputs (Level 3) [Member] | Commercial Real Estate [Member]
Assets [Abstract]
Loans & Leases, Net of Deferred Fees & Allowance		651,877	591,271
Estimated Fair Value [Member] | Significant Unobservable Inputs (Level 3) [Member] | Agricultural Real Estate [Member]
Assets [Abstract]
Loans & Leases, Net of Deferred Fees & Allowance		444,393	405,295
Estimated Fair Value [Member] | Significant Unobservable Inputs (Level 3) [Member] | Real Estate Construction [Member]
Assets [Abstract]
Loans & Leases, Net of Deferred Fees & Allowance		172,682	149,371
Estimated Fair Value [Member] | Significant Unobservable Inputs (Level 3) [Member] | Residential 1st Mortgages [Member]
Assets [Abstract]
Loans & Leases, Net of Deferred Fees & Allowance		241,174	207,431
Estimated Fair Value [Member] | Significant Unobservable Inputs (Level 3) [Member] | Home Equity Lines and Loans [Member]
Assets [Abstract]
Loans & Leases, Net of Deferred Fees & Allowance		30,495	32,360
Estimated Fair Value [Member] | Significant Unobservable Inputs (Level 3) [Member] | Agricultural [Member]
Assets [Abstract]
Loans & Leases, Net of Deferred Fees & Allowance		286,074	285,733
Estimated Fair Value [Member] | Significant Unobservable Inputs (Level 3) [Member] | Commercial [Member]
Assets [Abstract]
Loans & Leases, Net of Deferred Fees & Allowance		207,215	201,105
Estimated Fair Value [Member] | Significant Unobservable Inputs (Level 3) [Member] | Consumer & Other [Member]
Assets [Abstract]
Loans & Leases, Net of Deferred Fees & Allowance		6,706	6,416
Estimated Fair Value [Member] | Significant Unobservable Inputs (Level 3) [Member] | Leases [Member]
Assets [Abstract]
Loans & Leases, Net of Deferred Fees & Allowance		67,893	62,139
Estimated Fair Value [Member] | Significant Unobservable Inputs (Level 3) [Member] | Unallocated [Member]
Assets [Abstract]
Loans & Leases, Net of Deferred Fees & Allowance		(1,449)	(1,546)
Estimated Fair Value [Member] | Significant Unobservable Inputs (Level 3) [Member] | Obligations of States and Political Subdivisions [Member]
Assets [Abstract]
Investment Securities Held-to-Maturity		17,993	17,713
Estimated Fair Value [Member] | Significant Unobservable Inputs (Level 3) [Member] | Government Agency & Government-Sponsored Entities [Member]
Assets [Abstract]
Available-for-Sale Securities		0	0
Estimated Fair Value [Member] | Significant Unobservable Inputs (Level 3) [Member] | US Govt SBA [Member]
Assets [Abstract]
Available-for-Sale Securities		0
Estimated Fair Value [Member] | Significant Unobservable Inputs (Level 3) [Member] | US Treasury Notes [Member]
Assets [Abstract]
Available-for-Sale Securities			0
Estimated Fair Value [Member] | Significant Unobservable Inputs (Level 3) [Member] | Mortgage Backed Securities [Member]
Assets [Abstract]
Available-for-Sale Securities		0	0
Estimated Fair Value [Member] | Significant Unobservable Inputs (Level 3) [Member] | Other [Member]
Assets [Abstract]
Available-for-Sale Securities		$ 500	$ 0

[1] All Mortgage Backed Securities were issued by an agency or government sponsored entity of the U.S. government.