Variable Interest Entities (Details Textual) (USD $)	12 Months Ended
Jan. 31, 2013 Project	Jan. 31, 2012
Variable Interest Entity (Additional Textual) [Abstract]
Number of natural gas-fired power plant projects under development	2
Operating losses associated with moxie project entities	1,448,000	$ 302,000
Variable Interest Entity, Primary Beneficiary [Member]
Variable Interest Entities (Textual) [Abstract]
Prospective amount of loan to Moxie projects	9,000,000
Prospective amount of loan to Moxie Projects, maximum amount	10,000,000
Maturity date for all current and future loans	Sep. 30, 2014
Initial and additional development loans Moxie Project	5,479,000	1,500,000
Accrued interest receivable	783,000	$ 94,000
Project development financing expire date	Dec. 31, 2013

Current and future loans under prospective funding arrangement, expiration date.

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Project development financing expire date.

+ References

No definition available.

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Prospective funding arrangement, maximum capacity.

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No definition available.

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- Definition

Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 10

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-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 8

-Article 5

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- Definition

Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 10

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

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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.

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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.

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