Loans And Allowance For Loan Losses (Schedule Of Investment In Loans Related To Allowance For Loan Losses On The Basis Of Impairment Methodology) (Details) (USD $) In Thousands	Sep. 30, 2011	Dec. 31, 2010	Sep. 30, 2010
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans individually evaluated for impairment	$ 82,992	$ 102,770
Loans collectively evaluated for impairment	1,645,840	1,587,576
Total loans	1,728,832	1,690,346	1,537,708
Commercial [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans individually evaluated for impairment	18,649	27,941
Loans collectively evaluated for impairment	416,801	414,436
Total loans	435,450	442,377
Agricultural [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans individually evaluated for impairment	2,715	10,256
Loans collectively evaluated for impairment	61,941	72,124
Total loans	64,656	82,380
Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans individually evaluated for impairment	60,614	62,834
Loans collectively evaluated for impairment	960,611	912,691
Total loans	1,021,225	975,525
Consumer [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans individually evaluated for impairment	1,014	1,739
Loans collectively evaluated for impairment	206,487	188,325
Total loans	$ 207,501	$ 190,064

The balance of financing receivables that were collectively evaluated for impairment.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-URI http://asc.fasb.org/extlink&oid=6965416&loc=SL6953423-111524

-Subparagraph (h)

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- Definition

The balance of financing receivables that were individually evaluated for impairment.

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- Definition

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- Definition

Reflects the aggregate gross carrying amount of all categories of loans and leases held in portfolio, prior to deducting deferred income and the allowance for losses on loans and leases.

+ References

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

-Publisher AICPA

-Name Statement of Position (SOP)

-Number 01-6

-Paragraph 13

-Subparagraph e

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6375948&loc=d3e4428-111522

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