INVESTMENTS AND DEPOSITS (Details) (USD $)	12 Months Ended				12 Months Ended											24 Months Ended	12 Months Ended
	Jan. 31, 2014	Jan. 31, 2013	Jan. 31, 2012	Jan. 31, 2014 Big River [Member] Big River Resources Galva LLC [Member]	Jan. 31, 2014 Big River [Member] Burlington [Member] gal	Jan. 31, 2014 Big River [Member] Illinois [Member] gal	Jan. 31, 2014 Big River [Member] Dyersville [Member] l	Jan. 31, 2014 Big River [Member] WISCONSIN gal	Jan. 31, 2014 Big River [Member]	Jan. 31, 2013 Big River [Member]	Jan. 31, 2012 Big River [Member]	Jan. 31, 2014 Patriot [Member] Illinois [Member] gal	Jan. 31, 2014 Patriot [Member]	Jan. 31, 2013 Patriot [Member]	Jan. 31, 2012 Patriot [Member]	Jan. 31, 2013 Patriot [Member]	Jan. 31, 2012 Nu Gen Energy [Member]	Jan. 31, 2014 Nu Gen Energy [Member]	Nov. 30, 2011 Nu Gen Energy [Member]	Jul. 30, 2010 Nu Gen Energy [Member]	Jan. 31, 2014 Patriot And Big River [Member]
INVESTMENTS AND DEPOSITS (Details) [Line Items]
Agreement to Invest During Year									$ 20,000,000
Equity Method Investment, Ownership Percentage			48.00%	50.50%					10.00%				27.00%
Quantity of ethanol shipped					104,000,000	113,000,000	117,000,000	56,000,000				121,000,000
Income (Loss) from Equity Method Investments	17,175,000	627,000	21,532,000						8,800,000	300,000	6,900,000		8,400,000	400,000	5,300,000		9,300,000
Proceeds from Equity Method Investment, Dividends or Distributions									1,200,000	2,200,000	2,000,000		4,600,000			1,600,000
Equity Method Investments	71,189,000	59,959,000							40,042,000	32,438,000			31,147,000	27,521,000		27,521,000
Equity Method Investment, Underlying Equity in Net Assets									38,700,000				30,200,000
Equity Method Initial Investments													16,000,000
Business Combination, Step Acquisition, Equity Interest in Acquiree, Percentage																		99.00%	50.00%	48.00%
Business Acquisition, Percentage of Voting Interests Acquired																		100.00%
Retained Earnings, Undistributed Earnings from Equity Method Investees	32,600,000	21,200,000
Other Restricted Assets																					366,200,000
Proportionate Share of Restricted Net Assets																					$ 51,700,000