DERIVATIVE FINANCIAL INSTRUMENTS (Schedule of Outstanding Derivative Instruments and Cash Collateral) (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2018	Dec. 31, 2017
Fair values:
Collateral posted with brokers	$ 14,534	$ 8,021
Corn
Derivatives Coverage:
Derivatives coverage (as a percentage)	14.60%	3.10%
Period through which stated percent of needs are covered:
Maturity date	Sep. 30, 2019	Mar. 31, 2019
Soybean meal
Derivatives Coverage:
Derivatives coverage (as a percentage)	11.00%	1.70%
Period through which stated percent of needs are covered:
Maturity date	Dec. 30, 2019	Dec. 31, 2018
Commodity
Fair values:
Derivative assets, gross	$ 4,822	$ 722
Derivative liabilities, gross	(11,796)	(3,847)
Foreign currency
Fair values:
Derivative assets, gross	430	45
Derivative liabilities, gross	$ (1,943)	$ (211)