XML 85 R64.htm IDEA: XBRL DOCUMENT
v3.23.4

Stockholders' Equity and Warrant Liabilities - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands |  |  |  |  |  |  |  |  | 11 Months Ended | 12 Months Ended | 16 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Jul. 12, 2023 | Jul. 12, 2022 | Jun. 11, 2021 | Dec. 07, 2020 | Dec. 04, 2020 | Nov. 22, 2019 | Oct. 31, 2019 | May 03, 2017 | Apr. 30, 2022 | Oct. 31, 2023 | Oct. 31, 2022 | Oct. 31, 2021 | Oct. 31, 2023 | Oct. 11, 2023 | Oct. 10, 2023 | Apr. 08, 2021 | Apr. 07, 2021
Stockholders' Equity Note |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of incremental common stock shares approved |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 500,000,000.0 | 162,500,000 |
Common stock, shares authorized |  |  |  |  |  |  |  |  |  | 1,000,000,000 | 500,000,000 |  | 1,000,000,000 | 1,000,000,000.0 | 500,000,000.0 | 500,000,000.0 | 337,500,000
Drew down to fully repay debt outstanding |  |  |  |  |  |  |  |  |  | $ 100,500 |  | $ 10,175 |  |  |  |  |
Class of warrants or rights charge |  |  |  |  |  |  |  |  |  |  |  | $ 16,000 |  |  |  |  |
Reclassification of estimated fair value of warrant liability to additional paid in capital |  |  |  | $ 21,200 |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stockholders' Equity Note |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock issued during period shares new issues |  |  |  |  |  |  |  |  |  | 44,320,825 | 38,396,904 | 69,074,573 |  |  |  |  |
Common Stock | Series C Warrants |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stockholders' Equity Note |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock issued during period shares new issues |  |  |  |  |  |  |  |  |  |  | 0 | 14,026 |  |  |  |  |
Net proceeds from common stock and warrants |  |  |  |  |  |  |  |  |  |  |  | $ 300 |  |  |  |  |
Orion Energy Partners Investment Agent, LLC Credit Facility | Exercise Price 0.242 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stockholders' Equity Note |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Exercise price of warrants or rights |  |  |  | $ 0.242 |  |  |  |  |  |  |  |  |  |  |  |  |
Class of warrants or rights purchase |  |  |  | 2,700,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Class of warrants or rights issued value |  |  |  | $ 600 |  |  |  |  |  |  |  |  |  |  |  |  |
Orion Credit Agreement | Initial Funding Warrants |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stockholders' Equity Note |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of warrants or rights issued |  |  |  |  |  |  | 6,000,000 |  |  |  |  |  |  |  |  |  |
Exercise price of warrants or rights |  |  |  |  |  |  | $ 0.310 |  |  |  |  |  |  |  |  |  |
Orion Credit Agreement | Second Funding Warrants |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stockholders' Equity Note |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of warrants or rights issued |  |  |  |  |  | 14,000,000 |  |  |  |  |  |  |  |  |  |  |
Orion Credit Agreement | Second Funding Warrants | Exercise Price 0.242 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stockholders' Equity Note |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of warrants or rights issued |  |  |  |  |  | 8,000,000 |  |  |  |  |  |  |  |  |  |  |
Exercise price of warrants or rights |  |  |  |  |  | $ 0.242 |  |  |  |  |  |  |  |  |  |  |
Orion Credit Agreement | Second Funding Warrants | Exercise Price 0.620 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stockholders' Equity Note |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of warrants or rights issued |  |  |  |  |  | 6,000,000 |  |  |  |  |  |  |  |  |  |  |
Exercise price of warrants or rights |  |  |  |  |  | $ 0.620 |  |  |  |  |  |  |  |  |  |  |
2022 Open Market Sale Agreement | Jefferies LLC, B. Riley Securities, Inc., Barclays Capital Inc., BMO Capital Markets Corp., BofA Securities, Inc., Canacord Genuity LLC, Citigroup Global Markets Inc., J.P. Morgan Securities LLC and Loop Capital Markets LLC |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stockholders' Equity Note |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage of sales commission |  | 2.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
2022 Open Market Sale Agreement | Jefferies LLC, B. Riley Securities, Inc., Barclays Capital Inc., BMO Capital Markets Corp., BofA Securities, Inc., Canacord Genuity LLC, Citigroup Global Markets Inc., J.P. Morgan Securities LLC and Loop Capital Markets LLC | Common Stock |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stockholders' Equity Note |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Shares sold during the period |  |  |  |  |  |  |  |  |  | 44,300,000 |  |  | 62,800,000 |  |  |  |
Gross proceeds from issuance of common stock |  |  |  |  |  |  |  |  |  | $ 99,700 |  |  | $ 166,800 |  |  |  |
Gross proceeds from sale of common stock |  |  |  |  |  |  |  |  |  | 97,400 |  |  | 162,700 |  |  |  |
Payments of commissions |  |  |  |  |  |  |  |  |  | $ 2,300 |  |  | $ 4,100 |  |  |  |
Average sale price per share |  |  |  |  |  |  |  |  |  | $ 2.25 |  |  | $ 2.66 |  |  |  |
Shares remaining under the plan |  |  |  |  |  |  |  |  |  | 32,200,000 |  |  | 32,200,000 |  |  |  |
2022 Open Market Sale Agreement | Maximum | Jefferies LLC, B. Riley Securities, Inc., Barclays Capital Inc., BMO Capital Markets Corp., BofA Securities, Inc., Canacord Genuity LLC, Citigroup Global Markets Inc., J.P. Morgan Securities LLC and Loop Capital Markets LLC | Common Stock |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stockholders' Equity Note |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock issued during period shares new issues | 95,000,000.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
2021 Open Market Sale Agreement | Jefferies LLC and Barclays Capital Inc. | Common Stock |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stockholders' Equity Note |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock issued during period shares new issues |  |  |  |  |  |  |  |  | 64,000,000.0 |  | 19,900,000 |  |  |  |  |  |
Gross proceeds from issuance of common stock |  |  |  |  |  |  |  |  | $ 498,100 |  | $ 120,800 |  |  |  |  |  |
Gross proceeds from sale of common stock |  |  |  |  |  |  |  |  | 488,100 |  | 2,400 |  |  |  |  |  |
Payments of commissions |  |  |  |  |  |  |  |  | $ 10,000 |  | $ 118,300 |  |  |  |  |  |
Aggregate offering price |  |  | $ 500,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage of sales commission |  |  | 2.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |
Average sale price per share |  |  |  |  |  |  |  |  | $ 7.79 |  | $ 6.07 |  |  |  |  |  |
Underwriting Agreement |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stockholders' Equity Note |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock issued to underwriters |  |  |  |  | 19,822,219 |  |  |  |  |  |  |  |  |  |  |  |
Sale of stock, number of shares issued in transaction |  |  |  |  | 14,696,320 |  |  |  |  |  |  |  |  |  |  |  |
Sale of stock, price per share |  |  |  |  | $ 6.50 |  |  |  |  |  |  |  |  |  |  |  |
Stock issued during period shares new issues |  |  |  |  | 25,000,000 |  |  |  |  |  |  |  |  |  |  |  |
Gross proceeds from sale of common stock |  |  |  |  | $ 162,500 |  |  |  |  |  |  |  |  |  |  |  |
Underwriting discounts and commissions |  |  |  |  | $ 0.2275 |  |  |  |  |  |  |  |  |  |  |  |
Net proceeds from issuance of common stock |  |  |  |  | $ 156,400 |  |  |  |  |  |  |  |  |  |  |  |
Underwriting Agreement | Maximum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stockholders' Equity Note |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Option to purchase additional common stock shares |  |  |  |  | 5,177,781 |  |  |  |  |  |  |  |  |  |  |  |
Underwriting Public offering | Series C Warrants |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stockholders' Equity Note |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of warrants or rights issued |  |  |  |  |  |  |  | 1,000,000 |  |  |  |  |  |  |  |  |
Warrants issued, price per share |  |  |  |  |  |  |  | $ 19.20 |  |  |  |  |  |  |  |  |
Class of warrant or right term |  |  |  |  |  |  |  | 5 years |  |  |  |  |  |  |  |  |

X
- Definition This refers to the offering price for market offering program under the Open Market Sale Agreement with Jefferies LLC and Barclays Capital Inc.(Agent) + References No definition available. + Details
Name: | fcel_AggregateOfferingPrice
Namespace Prefix: | fcel_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition It refers to average sale price per share of shares sold under Open Market Sale Agreement + References No definition available. + Details
Name: | fcel_AverageSaleOfStockPricePerShare
Namespace Prefix: | fcel_
Data Type: | dtr-types:perShareItemType
Balance Type: | na
Period Type: | duration

X
- Definition Class of warrant or right term of warrants or rights. + References No definition available. + Details
Name: | fcel_ClassOfWarrantOrRightTermOfWarrantsOrRights
Namespace Prefix: | fcel_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Class of warrants or right to purchase + References No definition available. + Details
Name: | fcel_ClassOfWarrantsOrRightToPurchase
Namespace Prefix: | fcel_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition Class of warrants or rights charge. + References No definition available. + Details
Name: | fcel_ClassOfWarrantsOrRightsCharge
Namespace Prefix: | fcel_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Class of warrants or rights exercised value + References No definition available. + Details
Name: | fcel_ClassOfWarrantsOrRightsExercisedValue
Namespace Prefix: | fcel_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Represents number of warrants issued during the period. + References No definition available. + Details
Name: | fcel_ClassOfWarrantsOrRightsIssued
Namespace Prefix: | fcel_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Represents remaining common stock available for issuance under the open market agreement. + References No definition available. + Details
Name: | fcel_CommonStockRemainingSharesAvailableForIssuance
Namespace Prefix: | fcel_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition The number of common stock shares agreed upon to be newly issued. + References No definition available. + Details
Name: | fcel_CommonStockSharesAgreedToBeNewlyIssued
Namespace Prefix: | fcel_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition Its refers to gross proceeds from the Open Market Sale Agreement. + References No definition available. + Details
Name: | fcel_GrossProceedsFromIssuanceOfCommonStock
Namespace Prefix: | fcel_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Number of incremental common stock shares approved. + References No definition available. + Details
Name: | fcel_IncrementalAuthorizedCommonStockSharesApproved
Namespace Prefix: | fcel_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition Net proceeds from issuance of common stock. + References No definition available. + Details
Name: | fcel_NetProceedsFromIssuanceOfCommonStock
Namespace Prefix: | fcel_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Net proceeds from issuance of common stock and warrants + References No definition available. + Details
Name: | fcel_NetProceedsFromIssuanceOfCommonStockAndWarrants
Namespace Prefix: | fcel_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Option to purchase additional common stock shares. + References No definition available. + Details
Name: | fcel_OptionToPurchaseAdditionalCommonStockShares
Namespace Prefix: | fcel_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Payment of underwriting discounts and commissions + References No definition available. + Details
Name: | fcel_PaymentOfUnderwritingDiscountsAndCommissions
Namespace Prefix: | fcel_
Data Type: | dtr-types:perShareItemType
Balance Type: | na
Period Type: | duration

X
- Definition Its refers to the percentage of commission paid to Agents on Aggregate gross proceeds from the sale of shares under the Open Market Sale Agreement. + References No definition available. + Details
Name: | fcel_PercentageOfSalesCommission
Namespace Prefix: | fcel_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Reclassification to additional paid in capital revised estimated fair value of converted of warrant liability. + References No definition available. + Details
Name: | fcel_ReclassificationToAdditionalPaidInCapitalRevisedEstimatedFairValueOfConvertedOfWarrantLiability
Namespace Prefix: | fcel_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Number of new stock sold during the period. + References No definition available. + Details
Name: | fcel_StockIssuedDuringPeriodSharesSold
Namespace Prefix: | fcel_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Warrants issued, price per share. + References No definition available. + Details
Name: | fcel_WarrantsIssuedPricePerShare
Namespace Prefix: | fcel_
Data Type: | dtr-types:perShareItemType
Balance Type: | na
Period Type: | instant

X
- Definition Exercise price per share or per unit of warrants or rights outstanding. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 505 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Publisher FASB -URI https://asc.fasb.org//1943274/2147481112/505-10-50-3 + Details
Name: | us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:perShareItemType
Balance Type: | na
Period Type: | instant

X
- Definition The maximum number of common shares permitted to be issued by an entity's charter and bylaws. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.6-04(16)(a)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479617/946-210-S99-1 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(29)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1 + Details
Name: | us-gaap_CommonStockSharesAuthorized
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition The cash outflow for cost incurred directly with the issuance of an equity security. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482740/230-10-45-15 + Details
Name: | us-gaap_PaymentsOfStockIssuanceCosts
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The cash inflow from the additional capital contribution to the entity. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 45 -Paragraph 14 -Subparagraph (a) -SubTopic 10 -Topic 230 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482740/230-10-45-14 + Details
Name: | us-gaap_ProceedsFromIssuanceOfCommonStock
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 235 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08(f)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480678/235-10-S99-1 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482740/230-10-45-14 + Details
Name: | us-gaap_ProceedsFromLinesOfCredit
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The number of shares issued or sold by the subsidiary or equity method investee per stock transaction. + References No definition available. + Details
Name: | us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Price of a single share of a number of saleable stocks of a company. + References No definition available. + Details
Name: | us-gaap_SharePrice
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:perShareItemType
Balance Type: | na
Period Type: | instant

X
- Definition Number of new stock issued during the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 50 -Paragraph 2 -SubTopic 10 -Topic 505 -Publisher FASB -URI https://asc.fasb.org//1943274/2147481112/505-10-50-2 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 505 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481004/946-505-50-2 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 220 -Name Accounting Standards Codification -Section S99 -Paragraph 3 -Subparagraph (SX 210.6-09(4)(b)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147483575/946-220-S99-3 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 3 -Subparagraph (SX 210.6-03(i)(1)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479886/946-10-S99-3 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(28)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1 Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 505 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480008/505-10-S99-1 Reference 7: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(29)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1 + Details
Name: | us-gaap_StockIssuedDuringPeriodSharesNewIssues
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_StockholdersEquityNoteAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_StatementEquityComponentsAxis=us-gaap_CommonStockMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ClassOfWarrantOrRightAxis=fcel_SeriesCWarrantsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_CounterpartyNameAxis=fcel_OrionEnergyPartnersInvestmentAgentLLCCreditFacilityMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRangeAxis=fcel_ExercisePriceZeroPointTwoFourTwoMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_CounterpartyNameAxis=fcel_OrionCreditAgreementMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_TypeOfArrangementAxis=fcel_InitialFundingWarrantsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_TypeOfArrangementAxis=fcel_SecondFundingWarrantsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRangeAxis=fcel_ExercisePriceZeroPointSixTwoMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_SubsidiarySaleOfStockAxis=fcel_TwoZeroTwoTwoOpenMarketSaleAgreementMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_CounterpartyNameAxis=fcel_JefferiesLlcB.rileySecuritiesBarclaysCapitalIncBmocorpBofaSecuritiesCanacordGenuityLlcCitigroupGlobalMarketsIncJ.p.morganSecuritiesLlcAndLoopCapitalMarketsLlcMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_SubsidiarySaleOfStockAxis=fcel_TwoZeroTwoOneOpenMarketSaleAgreementMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_CounterpartyNameAxis=fcel_JefferiesLlcAndBarclaysCapitalIncMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_SubsidiarySaleOfStockAxis=fcel_UnderwritingAgreementMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_SubsidiarySaleOfStockAxis=fcel_UnderwritingPublicOfferingMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |