Restricted Cash - Summary of Allocation of Restricted Cash (Details) - USD ($) $ in Thousands	Jul. 31, 2024	Oct. 31, 2023	Jul. 31, 2023
Restricted Cash
Cash Restricted for Outstanding Letters of Credit	$ 14,152	$ 14,152
Cash Restricted for Crestmark Sale-Leaseback Transactions	2,907	2,901
Debt Service and Performance Reserves related to OpCo Financing Facility	22,535	19,698
Debt Service and Performance Reserves related to the Senior and Subordinated Back Leverage Loan Facilities	13,819	9,294
Other	5,421	3,579
Total Restricted Cash	58,834	49,624
Restricted Cash and Cash Equivalents - Short-Term	(9,686)	(5,159)	$ (6,078)
Restricted Cash and Cash Equivalents - Long-Term	$ 49,148	$ 44,465	$ 26,665

Cash restricted for crestmark sale leaseback transaction.

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Cash restricted for outstanding letters of credit.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The amount of debt service and performance reserves related to financing facility.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

The amount of debt service and performance reserves related to leverage loan facilities.

+ References

No definition available.

+ Details

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

- Definition

Other restricted cash.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Amount of cash restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(2))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(1))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 8
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482913/230-10-50-8

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(1)(a))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1

+ Details

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

Amount of cash and cash equivalents restricted as to withdrawal or usage, classified as current. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(1))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 230
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-Name Accounting Standards Codification
-Section 50
-Paragraph 8
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482913/230-10-50-8

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-Topic 230
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-Paragraph 4
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-4

+ Details

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

- Definition

Amount of cash and cash equivalents restricted as to withdrawal or usage, classified as noncurrent. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 8
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482913/230-10-50-8

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-Section 45
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-4

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 5
-SubTopic 210
-Topic 954
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477220/954-210-45-5

+ Details

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- References

No definition available.

+ Details

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