Variable Interest Entities (Details Textual) (USD $)	3 Months Ended
Apr. 30, 2013 Project	Apr. 30, 2012
Variable Interest Entities (Textual) [Abstract]
Net losses associated with moxie project entities	$ (530,000)	$ 176,000
Variable Interest Entities (Additional Textual) [Abstract]
Number of natural gas-fired power plant projects under development	2
Prospective amount of loan to Moxie projects	7,863,000
Gain from elimination of accounts of Moxie Liberty	1,120,000
Moxie Liberty LLC [Member]
Variable Interest Entities (Textual) [Abstract]
Company's amount of maximum exposure to loss	4,696,000
Notes receivable [Member] \| Moxie Liberty LLC [Member]
Variable Interest Entities (Textual) [Abstract]
Note Receivable from Moxie Liberty	4,125,000
Accrued Interest Receivable on Notes [Member] \| Moxie Liberty LLC [Member]
Variable Interest Entities (Textual) [Abstract]
Note Receivable from Moxie Liberty	571,000
Loans Receivable [Member]
Variable Interest Entities (Textual) [Abstract]
Annual interest rate	20.00%
Secured Debt [Member]
Variable Interest Entities (Textual) [Abstract]
Annual interest rate	10.00%
Variable interest entity, primary beneficiary [Member]
Variable Interest Entities (Textual) [Abstract]
Net losses associated with moxie project entities	261,000	281,000
Prospective amount of loan to Moxie Projects, maximum	$ 10,000,000

Prospective funding arrangement, maximum capacity.

No definition available.

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- Definition

Variable interest entity deconsolidation gain loss.

+ References

No definition available.

+ Details

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- Definition

Interest rate stated in the contractual debt agreement.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

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- Definition

Amount of Net Income (Loss) attributable to noncontrolling interest.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 810

-SubTopic 10

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-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

-Number 51

-Paragraph A1, A4, A5

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-Paragraph 38

-Subparagraph a

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-Publisher FASB

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-Name Accounting Research Bulletin (ARB)

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- Definition

The carrying amount of the consolidated Variable Interest Entity's assets included in the reporting entity's statement of financial position.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 810

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- Definition

The reporting entity's maximum amount of exposure to loss as a result of its involvement with the Variable Interest Entity (VIE).

+ References

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-Name Accounting Standards Codification

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-Paragraph C6

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- Definition

The amount of financial or other support the reporting entity has provided (explicitly or implicitly) to the Variable Interest Entity (VIE) that it was not previously contractually required to provide or that the reporting entity intends to provide, including, for example, situations in which the reporting entity assisted the VIE in obtaining another type of support.

+ References

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-Publisher FASB

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-Topic 810

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-Subparagraph (c)

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- Definition

Number of Variable Interest Entities (VIE) or potential VIEs for which the necessary information is unable to be obtained to: (1) determine whether the legal entity is a VIE, (2) determine whether it (the reporting entity) is the VIE's primary beneficiary, or (3) perform the accounting required to consolidate the VIE for which it is determined that it (the reporting entity) is the primary beneficiary.

+ References

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-Publisher FASB

-Name FASB Interpretation (FIN)

-Number 46R

-Paragraph 26

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