Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.7(d))

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Subparagraph d

-Article 9

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (b)(1)(ii)

-URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 6

-Section L

-Subsection 1

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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- Definition

Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

+ References

Reference 1: 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=28367877&loc=d3e4428-111522

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.7)

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Loans and Allowance - Composition of Loan Portfolio by Loan Class (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013	Mar. 31, 2013	Dec. 31, 2012
Loans:
Loans	$ 3,616,627	$ 3,632,409
Allowance for loan losses	(69,583)	(67,870)	(68,537)	(69,366)
Net Loans	3,547,044	3,564,539
Commercial and industrial loans
Loans:
Loans	787,390	761,705
Agricultural production financing and other loans to farmers
Loans:
Loans	99,226	114,348
Real estate loans - Construction
Loans:
Loans	155,117	177,082
Real estate loans - Commercial and farm land
Loans:
Loans	1,606,735	1,611,809
Real estate loans - Residential
Loans:
Loans	626,202	616,385
Allowance for loan losses	(13,908)	(15,077)	(15,479)	(14,157)
Real estate loans - Home equity
Loans:
Loans	256,790	255,223
Individuals' loans for household and other personal expenditures
Loans:
Loans	61,742	69,783
Allowance for loan losses	(2,410)	(2,515)	(2,689)	(2,593)
Lease financing receivables, net of unearned income
Loans:
Loans	1,378	1,545
Allowance for loan losses			(20)
Other loans
Loans:
Loans	$ 22,047	$ 24,529