Segment Reporting (Details) - Schedule Of Segment Results And Assets - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Oct. 31, 2019	Oct. 31, 2018	Oct. 31, 2019	Oct. 31, 2018
Segment Reporting Information [Line Items]
Net sales and revenue:		$ 86,671	$ 123,750	$ 297,114	$ 373,327
Segment gross profit (loss):		(1,758)	7,747	5,892	27,997
Income (loss) before income taxes:		(4,904)	3,755	(4,006)	16,263
Benefit (provision) for income taxes:		3,231	10,014	9,401	18,348
Segment profit (loss) (net of noncontrolling interests):		(2,052)	11,875	3,025	30,588
Sales of products, ethanol and by-products segment:		86,603	123,546	296,826	372,717
Ethanol [Member]
Segment Reporting Information [Line Items]
Net sales and revenue:		86,603	123,546	296,826	372,717
Segment gross profit (loss):		28	11,260	12,312	38,475
Income (loss) before income taxes:		(2,822)	8,405	3,491	29,491
Benefit (provision) for income taxes:		945	1,643	(160)	(1,806)
Segment profit (loss) (net of noncontrolling interests):		(2,330)	7,946	684	23,096
Sales of products, ethanol and by-products segment:		66,149	91,538	226,986	283,720
Refined Coal [Member]
Segment Reporting Information [Line Items]
Net sales and revenue:	[1]	68	204	288	610
Segment gross profit (loss):		(1,786)	(3,513)	(6,420)	(10,478)
Income (loss) before income taxes:		(1,648)	(4,240)	(6,351)	(11,887)
Benefit (provision) for income taxes:		2,181	8,318	9,282	19,914
Segment profit (loss) (net of noncontrolling interests):		607	4,260	3,209	8,549
Sales of products, ethanol and by-products segment:		68	204	288	610
Corporate and Other [Member]
Segment Reporting Information [Line Items]
Income (loss) before income taxes:		(434)	(410)	(1,146)	(1,341)
Benefit (provision) for income taxes:		105	53	279	240
Segment profit (loss) (net of noncontrolling interests):		(329)	(331)	(868)	(1,057)
Dried Distillers Grains [Member]
Segment Reporting Information [Line Items]
Sales of products, ethanol and by-products segment:		16,627	24,683	51,188	65,826
Non-Food Grade Corn Oil [Member]
Segment Reporting Information [Line Items]
Sales of products, ethanol and by-products segment:		3,099	4,964	12,681	15,019
Modified Distillers Grains [Member]
Segment Reporting Information [Line Items]
Sales of products, ethanol and by-products segment:		702	2,340	5,846	8,100
Other Segments [Member]
Segment Reporting Information [Line Items]
Sales of products, ethanol and by-products segment:		$ 26	$ 21	$ 125	$ 52

[1] The Company records sales in the refined coal segment net of the cost of coal as the Company purchases the coal feedstock from the customer to which refined coal is sold.