Fair Value of Financial Instruments (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Available-for-Sale: [Abstract]
Fair/Book Value, Total	$ 404,639	$ 417,991
Investment Securities Held-to-Maturity: [Abstract]
Fair Value	68,690
Carrying Amount [Member]
Assets [Abstract]
Cash and Cash Equivalents	83,677	129,426
Available-for-Sale: [Abstract]
Government Agency & Government-Sponsored Entities	28,436	26,823
Obligations of States and Political Subdivisions		5,665
Mortgage Backed Securities	324,929	352,772
Corporate Securities	49,380	22,558
Other	1,894	10,173
Fair/Book Value, Total	404,639	417,991
Investment Securities Held-to-Maturity: [Abstract]
Obligations of States and Political Subdivisions	65,685	65,694
Mortgage Backed Securities	45	484
Other	2,775	2,214
Fair Value	68,505	68,392
FHLB Stock	7,187	7,368
Loans & Leases, Net of Deferred Fees & Allowance [Abstract]
Commercial Real Estate	402,336	344,084
Agricultural Real Estate	324,688	309,115
Real Estate Construction	40,438	31,694
Residential 1st Mortgages	150,184	139,038
Home Equity Lines and Loans	32,710	38,807
Agricultural	244,209	210,595
Commercial	144,701	135,330
Consumer & Other	4,876	4,876
Leases	12,094
Unallocated Allowance	(2,274)	(854)
Total Loans & Leases, Net of Deferred Fees & Allowance	1,353,962	1,212,685
Accrued Interest Receivable	6,941	6,389
Deposits [Abstract]
Demand	495,963	462,251
Interest Bearing Transaction	291,795	259,141
Savings and Money Market	589,511	541,526
Time	430,422	459,108
Total Deposits	1,807,691	1,722,026
Subordinated Debentures	10,310	10,310
Accrued Interest Payable	352	498
Estimated Fair Value [Member]
Assets [Abstract]
Cash and Cash Equivalents	83,677	129,426
Available-for-Sale: [Abstract]
Government Agency & Government-Sponsored Entities	28,436	26,823
Obligations of States and Political Subdivisions		5,665
Mortgage Backed Securities	324,929	352,772
Corporate Securities	49,380	22,558
Other	1,894	10,173
Fair/Book Value, Total	404,639	417,991
Investment Securities Held-to-Maturity: [Abstract]
Obligations of States and Political Subdivisions	65,870	67,987
Mortgage Backed Securities	45	496
Other	2,775	2,214
Fair Value	68,690	70,697
Loans & Leases, Net of Deferred Fees & Allowance [Abstract]
Commercial Real Estate	403,790	349,524
Agricultural Real Estate	328,704	316,302
Real Estate Construction	40,800	32,024
Residential 1st Mortgages	153,352	144,203
Home Equity Lines and Loans	35,250	41,419
Agricultural	242,950	209,578
Commercial	145,131	134,647
Consumer & Other	4,912	4,847
Leases	11,851
Unallocated Allowance	(2,274)	(854)
Total Loans & Leases, Net of Deferred Fees & Allowance	1,364,466	1,231,690
Accrued Interest Receivable	6,941	6,389
Deposits [Abstract]
Demand	495,963	462,251
Interest Bearing Transaction	291,795	259,141
Savings and Money Market	589,511	541,526
Time	430,752	459,993
Total Deposits	1,808,021	1,722,911
Subordinated Debentures	6,224	5,750
Accrued Interest Payable	352	498
Estimated Fair Value [Member] \| Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Assets [Abstract]
Cash and Cash Equivalents	83,677	129,426
Available-for-Sale: [Abstract]
Government Agency & Government-Sponsored Entities	23,394	21,731
Obligations of States and Political Subdivisions		0
Mortgage Backed Securities	0	0
Corporate Securities	8,191	4,020
Other	1,584	9,863
Fair/Book Value, Total	33,169	35,614
Investment Securities Held-to-Maturity: [Abstract]
Obligations of States and Political Subdivisions	0	0
Mortgage Backed Securities	0	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
Unallocated Allowance	0	0
Total Loans & Leases, Net of Deferred Fees & Allowance	0	0
Accrued Interest Receivable	0	0
Deposits [Abstract]
Demand	495,963	462,251
Interest Bearing Transaction	291,795	259,141
Savings and Money Market	589,511	541,526
Time	0	0
Total Deposits	1,377,269	1,262,918
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
Available-for-Sale: [Abstract]
Government Agency & Government-Sponsored Entities	5,042	5,092
Obligations of States and Political Subdivisions		0
Mortgage Backed Securities	324,929	352,772
Corporate Securities	41,189	18,538
Other	310	310
Fair/Book Value, Total	371,470	376,712
Investment Securities Held-to-Maturity: [Abstract]
Obligations of States and Political Subdivisions	51,563	60,177
Mortgage Backed Securities	45	496
Other	2,775	2,214
Fair Value	54,383	62,887
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
Unallocated Allowance	0	0
Total Loans & Leases, Net of Deferred Fees & Allowance	0	0
Accrued Interest Receivable	6,941	0
Deposits [Abstract]
Demand	0	0
Interest Bearing Transaction	0	0
Savings and Money Market	0	0
Time	430,752	459,993
Total Deposits	430,752	459,993
Subordinated Debentures	6,224	5,750
Accrued Interest Payable	352	498
Estimated Fair Value [Member] \| Significant Unobservable Inputs (Level 3) [Member]
Assets [Abstract]
Cash and Cash Equivalents	0	0
Available-for-Sale: [Abstract]
Government Agency & Government-Sponsored Entities	0	0
Obligations of States and Political Subdivisions		5,665
Mortgage Backed Securities	0	0
Corporate Securities	0	0
Other	0	0
Fair/Book Value, Total	0	5,665
Investment Securities Held-to-Maturity: [Abstract]
Obligations of States and Political Subdivisions	14,307	7,810
Mortgage Backed Securities	0	0
Other	0	0
Fair Value	14,307	7,810
Loans & Leases, Net of Deferred Fees & Allowance [Abstract]
Commercial Real Estate	403,790	349,524
Agricultural Real Estate	328,704	316,302
Real Estate Construction	40,800	32,024
Residential 1st Mortgages	153,352	144,203
Home Equity Lines and Loans	35,250	41,419
Agricultural	242,950	209,578
Commercial	145,131	134,647
Consumer & Other	4,912	4,847
Leases	11,851
Unallocated Allowance	(2,274)	(854)
Total Loans & Leases, Net of Deferred Fees & Allowance	1,364,466	1,231,690
Accrued Interest Receivable	0	6,389
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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Fair value disclosure of accrued interest receivable at the end of period.

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No definition available.

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- Definition

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

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No definition available.

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- Definition

Fair value disclosure of loans secured by farmland.

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No definition available.

+ Details

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- Definition

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

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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

No definition available.

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- Definition

Fair value disclosure of demand deposits 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 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.

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No definition available.

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- Definition

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

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No definition available.

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- Definition

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

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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 available-for-sale.

+ 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 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.

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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 other real estate related to commercial real estate construction.

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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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)

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-Topic 320

-SubTopic 10

-Section 45

-Paragraph 1

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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

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

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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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- Definition

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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 325

-SubTopic 20

-Section 25

-Paragraph 1

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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

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Mortgage-Backed Securities

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

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

+ References

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