A valuation allowance for financing receivables that are expected to be uncollectible.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

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Amount of recovery of financing receivables doubtful of collection that were previously charged off.

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-Publisher FASB

-Name Accounting Standards Codification

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Amount of direct write-downs of financing receivables charged against the allowance.

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Amount of expense related to estimated loss from loan and lease transactions.

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-Topic 230

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-Number 210

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-Article 9

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Allowance for Loan and Lease Losses (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance at beginning of year				$ 41,685				$ 38,715	$ 41,685	$ 38,715	$ 36,808
Provision for loan and lease losses	2,866us-gaap_ProvisionForLoanAndLeaseLosses	2,553us-gaap_ProvisionForLoanAndLeaseLosses	2,751us-gaap_ProvisionForLoanAndLeaseLosses	6,331us-gaap_ProvisionForLoanAndLeaseLosses	2,049us-gaap_ProvisionForLoanAndLeaseLosses	5,149us-gaap_ProvisionForLoanAndLeaseLosses	1,862us-gaap_ProvisionForLoanAndLeaseLosses	637us-gaap_ProvisionForLoanAndLeaseLosses	14,501us-gaap_ProvisionForLoanAndLeaseLosses	9,697us-gaap_ProvisionForLoanAndLeaseLosses	8,202us-gaap_ProvisionForLoanAndLeaseLosses
Recoveries on loans and leases previously charged-off									3,990	4,820	8,209
Loans and leases charged-off									(18,727)	(11,547)	(14,504)
Balance at end of year	41,449				41,685				41,449	41,685	38,715
Commercial
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance at beginning of year				13,099				11,388	13,099	11,388
Provision for loan and lease losses									6,806	3,152
Recoveries on loans and leases previously charged-off									753	1,019
Loans and leases charged-off									(8,749)	(2,460)
Balance at end of year	11,909				13,099				11,909	13,099
Commercial Real Estate
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance at beginning of year				14,152				14,473	14,152	14,473
Provision for loan and lease losses									2,345	552
Recoveries on loans and leases previously charged-off									2,290	2,378
Loans and leases charged-off									(2,889)	(3,251)
Balance at end of year	15,898				14,152				15,898	14,152
Agricultural
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance at beginning of year				2,992				2,138	2,992	2,138
Provision for loan and lease losses									2,543	767
Recoveries on loans and leases previously charged-off									11	110
Loans and leases charged-off									(2,251)	(23)
Balance at end of year	3,295				2,992				3,295	2,992
Residential Real Estate
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance at beginning of year				3,720				3,543	3,720	3,543
Provision for loan and lease losses									215	1,055
Recoveries on loans and leases previously charged-off									148	158
Loans and leases charged-off									(342)	(1,036)
Balance at end of year	3,741				3,720				3,741	3,720
Consumer
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance at beginning of year				7,722				7,173	7,722	7,173
Provision for loan and lease losses									2,592	4,171
Recoveries on loans and leases previously charged-off									788	1,155
Loans and leases charged-off									(4,496)	(4,777)
Balance at end of year	$ 6,606				$ 7,722				$ 6,606	$ 7,722