Segment Reporting (Details) - Schedule of Segment Reporting Information, Profit Loss And Revenue Percentage (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Oct. 31, 2014	Oct. 31, 2013	Oct. 31, 2014	Oct. 31, 2013
Segment Reporting (Details) - Schedule of Segment Reporting Information, Profit Loss And Revenue Percentage [Line Items]
Net sales and revenues	$ 138,454	$ 166,188	$ 444,622	$ 520,001
Segment gross profit (loss)	36,497	18,028	111,957	37,924
Segment profit (loss)	40,577	15,852	119,415	32,042
Alternative Energy Segment [Member]
Segment Reporting (Details) - Schedule of Segment Reporting Information, Profit Loss And Revenue Percentage [Line Items]
Net sales and revenues	138,363	166,039	444,323	519,653
Segment gross profit (loss)	36,506	18,002	111,940	37,918
Segment profit (loss)	41,412	16,491	121,797	34,231
Real Estate Segment [Member]
Segment Reporting (Details) - Schedule of Segment Reporting Information, Profit Loss And Revenue Percentage [Line Items]
Net sales and revenues	91	149	299	348
Segment gross profit (loss)	(9)	26	17	6
Segment profit (loss)	(34)	(35)	(63)	(179)
Corporate Segment [Member]
Segment Reporting (Details) - Schedule of Segment Reporting Information, Profit Loss And Revenue Percentage [Line Items]
Segment profit (loss)	$ (801)	$ (604)	$ (2,319)	$ (2,010)

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

+ References

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- Definition

Revenue earned during the period from alternative energy sources (for example, ethanol, biomass, solar, geothermal, and wind power).

+ 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 FASB

-Name Accounting Standards Codification

-Topic 932

-SubTopic 235

-Section 50

-Paragraph 23

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=8451039&loc=d3e62136-109447

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 932

-SubTopic 235

-Section 50

-Paragraph 24

-URI http://asc.fasb.org/extlink&oid=8451039&loc=d3e62246-109447

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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.

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