Adjusted conversion price.

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After tax yield percentage.

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No definition available.

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Aggregate working capital loan amount maximum limit for determining disposition fee percentage.

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No definition available.

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Aggregate working capital loan amount minimum limit for determining disposition fee percentage.

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No definition available.

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Availability period for working capital loans.

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No definition available.

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Capacity of plant.

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No definition available.

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Conversion of stock conversion price.

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No definition available.

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- Definition

Debt instrument covenant distribution percentage.

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No definition available.

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- Definition

Disposition fee percentage.

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No definition available.

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Disposition fee percentage of total sale price.

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No definition available.

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Draw down fee percentage.

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No definition available.

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Loan Advance

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No definition available.

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Maturity date of each note under loan facility.

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No definition available.

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Number of projects completed with initial draw.

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Number of projects expected to be completed.

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No definition available.

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Percentage of construction budget.

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No definition available.

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Unlevered internal rate of return percentage to lender.

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No definition available.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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No definition available.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Total number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) issued to shareholders (includes related preferred shares that were issued, repurchased, and remain in the treasury). May be all or portion of the number of preferred shares authorized. Excludes preferred shares that are classified as debt.

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Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

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Percentage of subsidiary's or equity method investee's stock owned by parent immediately after all stock transactions.

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No definition available.

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Carrying amount, attributable to parent, of an entity's issued and outstanding stock which is not included within permanent equity. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. Includes stock with a put option held by an ESOP and stock redeemable by a holder only in the event of a change in control of the issuer.

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No definition available.

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Subsequent Events - Additional Information (Details)				12 Months Ended
Subsequent Events - Additional Information (Details)	Dec. 21, 2018 USD ($) Project MW	Dec. 13, 2018 USD ($) MW	Mar. 28, 2018 USD ($)	Oct. 31, 2018 USD ($) $ / shares shares	Jan. 02, 2019 $ / shares	Dec. 19, 2018 USD ($)	Aug. 27, 2018 $ / shares	Aug. 26, 2018 $ / shares	Oct. 31, 2017 USD ($) $ / shares shares	Apr. 30, 2016 USD ($)
Series C Preferred Stock [Member]
Subsequent Event [Line Items]
Preferred stock carrying value				$ 7,480,000					$ 27,700,000
Conversion of stock conversion price \| $ / shares				$ 1.50			$ 1.50	$ 1.84	$ 1.84
Adjusted conversion price \| $ / shares				$ 1.50
Series C Preferred Stock [Member] \| Convertible Preferred Offering [Member]
Subsequent Event [Line Items]
Preferred stock issued \| shares				8,992					33,300
Preferred stock outstanding \| shares				8,992					33,300
Preferred stock carrying value				$ 7,500,000					$ 27,700,000
Conversion of stock conversion price \| $ / shares				$ 1.50			$ 1.50
Subsequent Event [Member] \| Series C Preferred Stock [Member]
Subsequent Event [Line Items]
Adjusted conversion price \| $ / shares					$ 0.434
NRG Energy, Inc. [Member]
Subsequent Event [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity				$ 40,000,000
Long-term Line of Credit				0					0
NRG Energy, Inc. [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Long-term Line of Credit		$ 0
NRG Energy, Inc. [Member] \| Subsequent Event [Member] \| Tulare BioMAT [Member] \| California [Member]
Subsequent Event [Line Items]
Capacity of Plant \| MW		2.8
NRG Energy, Inc. [Member] \| Subsequent Event [Member] \| Central CA Fuel Cell 2, LLC [Member]
Subsequent Event [Line Items]
Loan Advance		$ 5,800,000
Maturity date of each note under loan facility		5 years
Generate Lending Construction Loan Agreement [Member] \| Subsequent Event [Member] \| FuelCell Energy Finance II, LLC [Member] \| Generate Lending, LLC [Member]
Subsequent Event [Line Items]
Loan Advance	$ 10,000,000
Percentage of construction budget	100.00%
Unlevered internal rate of return percentage to lender	10.00%
Availability period for working capital loans	36 months
Debt instrument, basis spread on variable rate	9.50%
Equity ownership	100.00%
Purchase price adjustment	50.00%
Draw down fee percentage	3.00%
Disposition fee percentage of total sale price	3.00%
Generate Lending Construction Loan Agreement [Member] \| Subsequent Event [Member] \| FuelCell Energy Finance II, LLC [Member] \| Generate Lending, LLC [Member] \| Maximum [Member]
Subsequent Event [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 300,000,000
Line of credit facility, current borrowing capacity	$ 100,000,000
Generate Lending Construction Loan Agreement [Member] \| Subsequent Event [Member] \| FuelCell Energy Finance II, LLC [Member] \| Generate Lending, LLC [Member] \| Minimum [Member]
Subsequent Event [Line Items]
Unlevered internal rate of return percentage to lender	10.00%
After-tax yield percentage	12.00%
Generate Lending Construction Loan Agreement [Member] \| Subsequent Event [Member] \| Bolthouse Farms [Member] \| California [Member] \| FuelCell Energy Finance II, LLC [Member] \| Generate Lending, LLC [Member]
Subsequent Event [Line Items]
Number of projects completed with initial draw \| Project	5
Generate Lending Construction Loan Agreement [Member] \| Subsequent Event [Member] \| PSEG Long Island [Member] \| FuelCell Energy Finance II, LLC [Member] \| Generate Lending, LLC [Member]
Subsequent Event [Line Items]
Capacity of Plant \| MW	39.8
Number of projects expected to be completed \| Project	3
Generate Lending Construction Loan Agreement [Member] \| Subsequent Event [Member] \| DEEP RFP [Member] \| FuelCell Energy Finance II, LLC [Member] \| Generate Lending, LLC [Member]
Subsequent Event [Line Items]
Capacity of Plant \| MW	22.2
Number of projects expected to be completed \| Project	2
Tranche One [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Aggregate working capital loan amount minimum limit	$ 100,000,000
Aggregate working capital loan amount maximum limit	$ 200,000,000
Disposition fee percentage	2.00%
Tranche Two [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Aggregate working capital loan amount minimum limit	$ 200,000,000
Aggregate working capital loan amount maximum limit	$ 300,000,000
Disposition fee percentage	1.00%
Hercules Capital, Inc. [Member]
Subsequent Event [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity				25,000,000						$ 25,000,000
Loan Advance			$ 13,100,000
Long-term Line of Credit			$ 11,900,000	$ 25,343,000					$ 21,468,000
Debt instrument, basis spread on variable rate				4.50%
Project Roundtrip Transaction [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity						$ 40,000,000