Capacity of natural gas fired power plant.

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Cash Received On Behalf Of Subsidiaries And Variable Interest Entity

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Development Success Fees Contingent Revenue

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Interest Rate On Cash Received

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Number of joint venture under contract with company.

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Percentage of development success fee to be shared with equipment seller not yet earned.

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Receivable interest rate stated percentage.

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- Definition

Variable Interest Entity Development Loan Funding Percentage

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Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities.

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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The distributions of earnings to an entity that is affiliated with the reporting entity by means of direct or indirect ownership.

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-Glossary Financing Activities

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

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-Name Accounting Standards Codification

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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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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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Special Purpose Entities - Additional Information (Detail) (USD $)	1 Months Ended	3 Months Ended	0 Months Ended	1 Months Ended
	Jan. 31, 2015	Apr. 30, 2015 Project JointVenture	Apr. 30, 2015	Aug. 31, 2014 MW
Variable Interest Entity [Line Items]
Number of natural gas-fired power plants		2
Number of joint ventures		2	2
Cash distributions to joint venture partner	$ 25,000,000
Moxie Freedom LLC [Member]
Variable Interest Entity [Line Items]
Nominal capacity of natural gas-fired power plant				1,000
Interest rate on loan receivable			20.00%
Notes receivable and accrued interest		2,830,000	2,830,000
Maturity date of loan		Dec. 31, 2017
Project development support costs included in accrued expenses	275,000	262,000	262,000
Development success fee		6,000,000
Loan approved percentage		40.00%
Cash received pursuant to participation agreement		1,042,000
Percentage of development success fee to be shared with equipment seller, not yet earned		40.00%
Interest rate on cash received		20.00%
Moxie Freedom LLC [Member] \| Maximum [Member]
Variable Interest Entity [Line Items]
Development loans to Moxie Freedom				6,000,000