Lease Agreements for Projects

No definition available.

Name:	fcel_LeaseAgreementsforProjects
Namespace Prefix:	fcel_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Planned expenditures Phase 1

+ References

No definition available.

+ Details

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Namespace Prefix:	fcel_
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Period Type:	duration

- Definition

Planned expenditures both phases

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Proceeds received from sale of project assets

+ References

No definition available.

+ Details

Name:	fcel_Proceedsreceivedfromsaleofprojectassets
Namespace Prefix:	fcel_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

Reserves for obligations

+ References

No definition available.

+ Details

Name:	fcel_Reservesforobligations
Namespace Prefix:	fcel_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

total potential funding

+ References

No definition available.

+ Details

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Namespace Prefix:	fcel_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of assets pledged to secure a debt instrument.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64711-112823

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of unused borrowing capacity under the long-term financing arrangement that is available to the entity as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Amount of increase (decrease) to previously recorded tax expense. Includes, but is not limited to, significant settlements of income tax disputes, and unusual tax positions or infrequent actions taken by the entity, including tax assessment reversal, and IRS tax settlement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 25
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=51675352&loc=d3e28446-109314

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 25
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=51675352&loc=d3e28511-109314

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	debit
Period Type:	duration

- Details

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Namespace Prefix:
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Subsequent events (Details) - USD ($) $ in Millions		12 Months Ended
Subsequent events (Details) - USD ($) $ in Millions	Nov. 10, 2015	Oct. 31, 2015	Dec. 23, 2015	Nov. 09, 2015
Subsequent Event [Line Items]
Tax Adjustments, Settlements, and Unusual Provisions		$ 10.0
Lease Agreements for Projects			$ 30.0
Proceeds received from sale of project assets			8.8
Reserves for obligations			$ 10.0
CT Dept of Economic & Community Development [Member]
Subsequent Event [Line Items]
Debt Instrument, Face Amount				$ 10.0
Debt Instrument, Collateral Amount				$ 10.0
Debt Instrument, Interest Rate, Stated Percentage				2.00%
Debt Instrument, Term	15 years
Debt Instrument, Unused Borrowing Capacity, Amount				$ 10.0
Planned expenditures Phase 1	$ 23.0
Planned expenditures both phases	65.0
Total potential funding	$ 20.0