Segment Reporting (Details) - Schedule of Segment Reporting Information, Profit Loss and Revenue Percentage (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jul. 31, 2013	Jul. 31, 2012	Jul. 31, 2013	Jul. 31, 2012
Segment Reporting (Details) - Schedule of Segment Reporting Information, Profit Loss and Revenue Percentage [Line Items]
Net sales and revenue	$ 175,717	$ 153,164	$ 354,464	$ 304,171
Gross profit	11,005	6,958	20,111	12,456
Income from continuing operations before income taxes	10,445	1,693	16,399	3,580
Interest expense	(1,029)	(1,173)	(2,084)	(2,505)
Alternative Energy Segment [Member] \| Ethanol [Member]
Segment Reporting (Details) - Schedule of Segment Reporting Information, Profit Loss and Revenue Percentage [Line Items]
Sale of Product	76.00%	76.00%	75.00%	77.00%
Alternative Energy Segment [Member] \| Distillers Grains [Member]
Segment Reporting (Details) - Schedule of Segment Reporting Information, Profit Loss and Revenue Percentage [Line Items]
Sale of Product	21.00%	21.00%	22.00%	20.00%
Alternative Energy Segment [Member] \| Other Products [Member]
Segment Reporting (Details) - Schedule of Segment Reporting Information, Profit Loss and Revenue Percentage [Line Items]
Sale of Product	3.00%	3.00%	3.00%	3.00%
Alternative Energy Segment [Member]
Segment Reporting (Details) - Schedule of Segment Reporting Information, Profit Loss and Revenue Percentage [Line Items]
Net sales and revenue	175,290	152,778	353,614	303,442
Gross profit	10,890	7,027	19,916	12,537
Income from continuing operations before income taxes	11,114	2,432	17,740	4,901
Sale of Product	100.00%	100.00%	100.00%	100.00%
Real Estate Segment [Member]
Segment Reporting (Details) - Schedule of Segment Reporting Information, Profit Loss and Revenue Percentage [Line Items]
Net sales and revenue	427	386	850	729
Gross profit	115	(69)	195	(81)
Income from continuing operations before income taxes	53	(114)	72	(216)
Lease revenue	100.00%	100.00%	100.00%	100.00%
Corporate Segment [Member]
Segment Reporting (Details) - Schedule of Segment Reporting Information, Profit Loss and Revenue Percentage [Line Items]
Income from continuing operations before income taxes	(732)	(623)	(1,432)	(1,131)
Interest expense	(8)	(21)	(17)	(23)
Interest income	$ 18	$ 19	$ 36	$ 49

The percentage of net lease revenue to total net revenue from the lease as of year end.

No definition available.

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- Definition

The percentage of net product revenue to total net revenue from the sale of goods as of year end.

+ References

No definition available.

+ Details

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- Details

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- Definition

Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity.

+ References

+ Details

Name:	us-gaap_GrossProfit
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

This element represents the income or loss from continuing operations attributable to the economic entity which may also be defined as revenue less expenses from ongoing operations, after income or loss from equity method investments, but before income taxes, extraordinary items, and noncontrolling interest.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 10

-Article 5

+ Details

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- Definition

Amount of the cost of borrowed funds accounted for as interest expense.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6450988&loc=d3e26243-108391

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-04.9)

-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 9

-Article 9

+ Details

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- Definition

Amount before accretion (amortization) of purchase discount (premium) of interest income on nonoperating securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.7(b))

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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- Definition

Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.1)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Article 5

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