CONSOLIDATED STATEMENTS OF OPERATIONS (USD $) Share data in Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Jan. 31, 2013	Jan. 31, 2012	Jan. 31, 2011
Net sales and revenue	$ 657,737,000	$ 409,923,000	$ 235,545,000
Cost of sales	644,201,000	375,921,000	201,990,000
Gross profit	13,536,000	34,002,000	33,555,000
Selling, general and administrative expenses	(12,545,000)	(10,377,000)	(8,810,000)
Equity in income of unconsolidated ethanol affiliates	627,000	21,532,000	14,558,000
Bargain purchase gain, net	8,990,000	3,541,000
Income from synthetic fuel investments		2,883,000
Interest income	166,000	416,000	436,000
Interest expense	(4,870,000)	(3,459,000)	(2,935,000)
Loss on early termination of debt		(1,000)	(48,000)
Other income	80,000	625,000	5,000
Loss on disposal of real estate and property and equipment, net	(480,000)
Loss on derivative financial instruments	(370,000)	(1,148,000)	(2,116,000)
(Loss) income from continuing operations before income taxes	(3,856,000)	48,014,000	34,645,000
Benefit (provision) for income taxes	1,639,000	(15,957,000)	(12,358,000)
(Loss) income from continuing operations	(2,217,000)	32,057,000	22,287,000
Income (loss) from discontinued operations, net of tax	500,000	1,206,000	(13,706,000)
Gain on disposal of discontinued operations, net of tax	129,000	435,000	161,000
Net (loss) income	(1,588,000)	33,698,000	8,742,000
Net income attributable to noncontrolling interests	(707,000)	(5,428,000)	(3,673,000)
Net (loss) income attributable to REX common shareholders	(2,295,000)	28,270,000	5,069,000
Weighted average shares outstanding – basic (in Shares)	8,272	9,117	9,651
Basic (loss) income per share from continuing operations attributable to REX common shareholders (in Dollars per share)	$ (0.35)	$ 2.92	$ 1.93
Basic income (loss) per share from discontinued operations attributable to REX common shareholders (in Dollars per share)	$ 0.06	$ 0.13	$ (1.42)
Basic income per share on disposal of discontinued operations attributable to REX common shareholders (in Dollars per share)	$ 0.01	$ 0.05	$ 0.02
Basic net (loss) income per share attributable to REX common shareholders (in Dollars per share)	$ (0.28)	$ 3.10	$ 0.53
Weighted average shares outstanding – diluted (in Shares)	8,272	9,187	9,825
Diluted (loss) income per share from continuing operations attributable to REX common shareholders (in Dollars per share)	$ (0.35)	$ 2.90	$ 1.89
Diluted income per share from discontinued operations attributable to REX common shareholders (in Dollars per share)	$ 0.06	$ 0.13	$ (1.39)
Diluted gain per share on disposal of discontinued operations attributable to REX common shareholders (in Dollars per share)	$ 0.01	$ 0.05	$ 0.02
Diluted net (loss) income per share attributable to REX common shareholders (in Dollars per share)	$ (0.28)	$ 3.08	$ 0.52
(Loss) income from continuing operations, net of tax	(2,924,000)	26,629,000	18,614,000
Income (loss) from discontinued operations, net of tax	629,000	1,641,000	(13,545,000)
Net (loss) income	$ (2,295,000)	$ 28,270,000	$ 5,069,000