FAIR VALUE - Quantitative Information about Level 3 Value Measurements - (Details) - Non-recurring basis - Level 3 - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2016	Dec. 31, 2015
Impaired Loans
Quantitative information about level 3 fair value measurements for financial instruments measured at fair value
Fair Value	$ 506
Unobservable Inputs
Discount rate (as a percent)	10.00%
Impaired Loans \| Average
Quantitative information about level 3 fair value measurements for financial instruments measured at fair value
Fair Value		$ 1,140
Unobservable Inputs
Discount rate (as a percent)		10.00%
Impaired Loans \| Farm \| Sales comparison approach
Quantitative information about level 3 fair value measurements for financial instruments measured at fair value
Fair Value	$ 68	$ 58
Unobservable Inputs
Discount rate (as a percent)	10.00%	10.00%
Impaired Loans \| Farm \| Sales comparison approach \| Average
Unobservable Inputs
Discount rate (as a percent)	10.00%	10.00%
Impaired Loans \| Other commercial real estate \| Sales comparison approach
Quantitative information about level 3 fair value measurements for financial instruments measured at fair value
Fair Value	$ 438
Impaired Loans \| Other commercial real estate \| Sales comparison approach \| Minimum
Unobservable Inputs
Discount rate (as a percent)	0.00%
Impaired Loans \| Other commercial real estate \| Sales comparison approach \| Maximum
Unobservable Inputs
Discount rate (as a percent)	20.00%
Impaired Loans \| Other \| Sales comparison approach
Quantitative information about level 3 fair value measurements for financial instruments measured at fair value
Fair Value		$ 1,082
Impaired Loans \| Other \| Sales comparison approach \| Minimum
Unobservable Inputs
Discount rate (as a percent)		0.00%
Impaired Loans \| Other \| Sales comparison approach \| Maximum
Unobservable Inputs
Discount rate (as a percent)		20.00%
Mortgage servicing rights \| Cash flow analysis
Quantitative information about level 3 fair value measurements for financial instruments measured at fair value
Fair Value	$ 474	$ 531
Unobservable Inputs
Discount rate (as a percent)	10.00%	10.00%

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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- Definition

Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)
-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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