Fair Value of Financial Instruments (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Investment Securities Available-for-Sale [Abstract]
Fair/Book Value	$ 366,542us-gaap_AvailableForSaleSecurities	$ 404,639us-gaap_AvailableForSaleSecurities
Investment Securities Held-to-Maturity [Abstract]
Fair Value	64,635	68,690
Carrying Amount [Member]
Assets [Abstract]
Cash and Cash Equivalents	77,125	83,677
Investment Securities Available-for-Sale [Abstract]
Government Agency & Government-Sponsored Entities	78,109	28,436
Mortgage Backed Securities	287,948	324,929
Corporate Securities		49,380
Other	485	1,894
Fair/Book Value	366,542	404,639
Investment Securities Held-to-Maturity [Abstract]
Obligations of States and Political Subdivisions	61,716	65,685
Mortgage Backed Securities		45
Other	2,147	2,775
Fair Value	63,863	68,505
FHLB Stock	7,677	7,187
Loans & Leases, Net of Deferred Fees & Allowance [Abstract]
Commercial Real Estate	484,061	402,336
Agricultural Real Estate	353,022	324,688
Real Estate Construction	94,850	40,438
Residential 1st Mortgages	170,858	150,184
Home Equity Lines and Loans	30,591	32,710
Agricultural	275,859	244,209
Commercial	222,624	144,701
Consumer & Other	4,501	4,876
Leases	42,006	12,094
Unallocated Allowance	(1,529)	(2,274)
Total Loans & Leases, Net of Deferred Fees & Allowance	1,676,843	1,353,962
Accrued Interest Receivable	7,797	6,941
Deposits [Abstract]
Demand	610,133	495,963
Interest Bearing Transaction	341,397	291,795
Savings and Money Market	644,260	589,511
Time	468,283	430,422
Total Deposits	2,064,073	1,807,691
Subordinated Debentures	10,310	10,310
Accrued Interest Payable	378	352
Estimated Fair Value [Member]
Assets [Abstract]
Cash and Cash Equivalents	77,125	83,677
Investment Securities Available-for-Sale [Abstract]
Government Agency & Government-Sponsored Entities	78,109	28,436
Mortgage Backed Securities	287,948	324,929
Corporate Securities		49,380
Other	485	1,894
Fair/Book Value	366,542	404,639
Investment Securities Held-to-Maturity [Abstract]
Obligations of States and Political Subdivisions	62,488	65,870
Mortgage Backed Securities		45
Other	2,147	2,775
Fair Value	64,635	68,690
Loans & Leases, Net of Deferred Fees & Allowance [Abstract]
Commercial Real Estate	481,037	403,790
Agricultural Real Estate	353,288	328,704
Real Estate Construction	95,022	40,800
Residential 1st Mortgages	173,916	153,352
Home Equity Lines and Loans	32,456	35,250
Agricultural	274,195	242,950
Commercial	222,175	145,131
Consumer & Other	4,535	4,912
Leases	40,298	11,851
Unallocated Allowance	(1,529)	(2,274)
Total Loans & Leases, Net of Deferred Fees & Allowance	1,675,393	1,364,466
Accrued Interest Receivable	7,797	6,941
Deposits [Abstract]
Demand	610,133	495,963
Interest Bearing Transaction	341,397	291,795
Savings and Money Market	644,260	589,511
Time	468,161	430,752
Total Deposits	2,063,951	1,808,021
Subordinated Debentures	6,227	6,224
Accrued Interest Payable	378	352
Estimated Fair Value [Member] \| Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Assets [Abstract]
Cash and Cash Equivalents	77,125	83,677
Investment Securities Available-for-Sale [Abstract]
Government Agency & Government-Sponsored Entities	10,005	23,394
Mortgage Backed Securities	0	0
Corporate Securities		8,191
Other	175	1,584
Fair/Book Value	10,180	33,169
Investment Securities Held-to-Maturity [Abstract]
Obligations of States and Political Subdivisions	0	0
Mortgage Backed Securities		0
Other	0	0
Fair Value	0	0
Loans & Leases, Net of Deferred Fees & Allowance [Abstract]
Commercial Real Estate	0	0
Agricultural Real Estate	0	0
Real Estate Construction	0	0
Residential 1st Mortgages	0	0
Home Equity Lines and Loans	0	0
Agricultural	0	0
Commercial	0	0
Consumer & Other	0	0
Leases	0	0
Unallocated Allowance	0	0
Total Loans & Leases, Net of Deferred Fees & Allowance	0	0
Accrued Interest Receivable	0	0
Deposits [Abstract]
Demand	610,133	495,963
Interest Bearing Transaction	341,397	291,795
Savings and Money Market	644,260	589,511
Time	0	0
Total Deposits	1,595,790	1,377,269
Subordinated Debentures	0	0
Accrued Interest Payable	0	0
Estimated Fair Value [Member] \| Other Observable Inputs (Level 2) [Member]
Assets [Abstract]
Cash and Cash Equivalents	0	0
Investment Securities Available-for-Sale [Abstract]
Government Agency & Government-Sponsored Entities	68,104	5,042
Mortgage Backed Securities	287,948	324,929
Corporate Securities		41,189
Other	310	310
Fair/Book Value	356,362	371,470
Investment Securities Held-to-Maturity [Abstract]
Obligations of States and Political Subdivisions	49,085	51,563
Mortgage Backed Securities		45
Other	2,147	2,775
Fair Value	51,232	54,383
Loans & Leases, Net of Deferred Fees & Allowance [Abstract]
Commercial Real Estate	0	0
Agricultural Real Estate	0	0
Real Estate Construction	0	0
Residential 1st Mortgages	0	0
Home Equity Lines and Loans	0	0
Agricultural	0	0
Commercial	0	0
Consumer & Other	0	0
Leases	0	0
Unallocated Allowance	0	0
Total Loans & Leases, Net of Deferred Fees & Allowance	0	0
Accrued Interest Receivable	7,797	6,941
Deposits [Abstract]
Demand	0	0
Interest Bearing Transaction	0	0
Savings and Money Market	0	0
Time	468,161	430,752
Total Deposits	468,161	430,752
Subordinated Debentures	6,227	6,224
Accrued Interest Payable	378	352
Estimated Fair Value [Member] \| Significant Unobservable Inputs (Level 3) [Member]
Assets [Abstract]
Cash and Cash Equivalents	0	0
Investment Securities Available-for-Sale [Abstract]
Government Agency & Government-Sponsored Entities	0	0
Mortgage Backed Securities	0	0
Corporate Securities		0
Other	0	0
Fair/Book Value	0	0
Investment Securities Held-to-Maturity [Abstract]
Obligations of States and Political Subdivisions	13,403	14,307
Mortgage Backed Securities		0
Other	0	0
Fair Value	13,403	14,307
Loans & Leases, Net of Deferred Fees & Allowance [Abstract]
Commercial Real Estate	481,037	403,790
Agricultural Real Estate	353,288	328,704
Real Estate Construction	95,022	40,800
Residential 1st Mortgages	173,916	153,352
Home Equity Lines and Loans	32,456	35,250
Agricultural	274,195	242,950
Commercial	222,175	145,131
Consumer & Other	4,535	4,912
Leases	40,298	11,851
Unallocated Allowance	(1,529)	(2,274)
Total Loans & Leases, Net of Deferred Fees & Allowance	1,675,393	1,364,466
Accrued Interest Receivable	0	0
Deposits [Abstract]
Demand	0	0
Interest Bearing Transaction	0	0
Savings and Money Market	0	0
Time	0	0
Total Deposits	0	0
Subordinated Debentures	0	0
Accrued Interest Payable	$ 0	$ 0

Fair value disclosure of accrued interest payable at the end of the period.

No definition available.

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- Definition

Fair value disclosure of accrued interest receivable at the end of period.

+ References

No definition available.

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- Definition

Fair value disclosure of loans and lines of credit made to farmers to finance agricultural production.

+ References

No definition available.

+ Details

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- Definition

Fair value disclosure of loans secured by farmland.

+ References

No definition available.

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- Definition

Fair value disclosure of commercial loans at the end of the period.

+ References

No definition available.

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- Definition

Fair value disclosure of loans solely used for business purposes.

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No definition available.

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- Definition

Fair value disclosure of consumer and other loans at the end of the period.

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No definition available.

+ Details

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- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents corporate securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities.

+ References

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- Definition

Fair value disclosure of demand deposits at the end of the period.

+ References

No definition available.

+ Details

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- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents debentures, notes and other debt securities issued by US government agencies and US government sponsored entities. Excludes US treasury Securities, as of the balance sheet date which have been categorized as available-for-sale.

+ References

No definition available.

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- Definition

Fair value disclosure of home equity lines of credit at the end of the period.

+ References

No definition available.

+ Details

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- Definition

Fair value disclosure of interest bearing deposit at the end of the period.

+ References

No definition available.

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- Definition

Fair value disclosure of leases at the end of the period.

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No definition available.

+ Details

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- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents bonds or similar securities issued by state, city, or local US governments or the agencies operated by state, city, or local governments as of the balance sheet date which have been categorized as Held-to-Maturity. The held-to-Maturity category is for those securities that the Entity has the positive intent and ability to hold until maturity.

+ References

No definition available.

+ Details

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- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This element represents the fair value of securities/investments categorized as other which are not in and of themselves material enough to require separate disclosure.

+ References

No definition available.

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- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This element represents the fair value of securities/investments categorized as other which are not in and of themselves material enough to require separate disclosure.

+ References

No definition available.

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- Definition

Fair value disclosure for loans related to commercial real estate construction.

+ References

No definition available.

+ Details

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- Definition

Fair value disclosure of residential first mortgages at the end of the period.

+ References

No definition available.

+ Details

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- Definition

Fair value disclosure of savings and money market instrument at the end of the period.

+ References

No definition available.

+ Details

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- Definition

Fair value disclosure of subordinated debentures at the end of the period.

+ References

No definition available.

+ Details

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- Definition

Fair value disclosure of time deposits at the end of the period.

+ References

No definition available.

+ Details

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- Definition

Fair value disclosure of unallocated loan allowances at the end of the period.

+ References

No definition available.

+ Details

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- Definition

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 25

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558

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-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 5

-Subparagraph (aa)

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-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 45

-Paragraph 1

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- Definition

Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash

-URI http://asc.fasb.org/extlink&oid=6506951

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash Equivalents

-URI http://asc.fasb.org/extlink&oid=6507016

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- Definition

Fair value portion of deposit liabilities held by the entity, including, but not limited to, foreign and domestic, interest and noninterest bearing, demand deposits, saving deposits, negotiable orders of withdrawal (NOW) and time deposits.

+ References

No definition available.

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- Definition

Fair value of investments in debt securities classified as held-to-maturity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 5

-Subparagraph (aa)

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-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 5

-Subparagraph (f)

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-Topic 320

-SubTopic 10

-Section 50

-Paragraph 5

-Subparagraph (a)

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- Definition

Fair value portion of investments in Federal Home Loan Bank (FHLBank) stock.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 325

-SubTopic 20

-Section 25

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=29638263&loc=d3e39828-111592

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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Glossary Loan

-URI http://asc.fasb.org/extlink&oid=6517073

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- Definition

Fair value of securitized, pay-through debt securities collateralized by real estate mortgage loans classified as available-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Mortgage-Backed Securities

-URI http://asc.fasb.org/extlink&oid=6517959

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- Definition

Fair value of securitized, pay-through debt securities collateralized by real estate mortgage loans classified as held-to-maturity.

+ References

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