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DERIVATIVE FINANCIAL INSTRUMENTS (Details) gal in Millions, bu in Millions | 12 Months Ended
--- | ---
Jan. 31, 2018 USD ($) gal bu | Jan. 31, 2017 USD ($) bu | Jan. 31, 2016 USD ($)
DERIVATIVE FINANCIAL INSTRUMENTS (Details) [Line Items] |  |  |
Debt Instrument, Collateral Amount | $ |  | $ 354,000 |
Derivative, Gain on Derivative | $ | $ 1,317,000 | $ 2,131,000 | $ 382,000
Corn [Member] |  |  |
DERIVATIVE FINANCIAL INSTRUMENTS (Details) [Line Items] |  |  |
Forward Purchase Contracts, Quantity | bu | 11.7 | 5.3 |
Corn [Member] | Short/Sell [Member] |  |  |
DERIVATIVE FINANCIAL INSTRUMENTS (Details) [Line Items] |  |  |
Commodity Futures, Quantity | bu | 2.5 | 0.7 |
Ethanol [Member] | Short/Sell [Member] |  |  |
DERIVATIVE FINANCIAL INSTRUMENTS (Details) [Line Items] |  |  |
Commodity Futures, Quantity | gal | 2.8 |  |
Ethanol [Member] | Long/Buy [Member] |  |  |
DERIVATIVE FINANCIAL INSTRUMENTS (Details) [Line Items] |  |  |
Commodity Futures, Quantity | gal | 2.8 |  |

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