Debt Instrument, Commitment Fee Per Annum Threshold Percentage

No definition available.

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- Definition

Debt Instrument, Covenant, Borrowing Base Qualified Cash Threshold

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Debt Instrument, Covenant, Borrowing Base Threshold

+ References

No definition available.

+ Details

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Namespace Prefix:	flnc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Debt Instrument, Covenant, Excess Availability, Line Cap Percentage Threshold

+ References

No definition available.

+ Details

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Namespace Prefix:	flnc_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Debt Instrument, Covenant, Line Cap Additional Threshold Amount, Excess Availability

+ References

No definition available.

+ Details

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

- Definition

Debt Instrument, Covenant, Line Cap Additional Threshold Amount, Total Liquidity

+ References

No definition available.

+ Details

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

- Definition

Debt Instrument, Covenant, Line Cap Additional Threshold Amount, Total Liquidity, Scenario Two

+ References

No definition available.

+ Details

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

- Definition

Debt Instrument, Covenant, Line Cap, Scenario One

+ References

No definition available.

+ Details

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

- Definition

Debt Instrument, Covenant, Net Leverage Ratio, Maximum Threshold

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Debt Instrument, Covenant Relief, Excess Availability, Line Cap Percentage Threshold

+ References

No definition available.

+ Details

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Data Type:	dtr-types:percentItemType
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Period Type:	instant

- Definition

Debt Instrument, Covenant, Total Liquidity, Line Cap Percentage Threshold

+ References

No definition available.

+ Details

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Data Type:	dtr-types:percentItemType
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Period Type:	instant

- Definition

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

+ References

No definition available.

+ Details

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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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

- Definition

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.

+ References

+ Details

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

- Definition

The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

+ References

No definition available.

+ Details

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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
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-Publisher FASB
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Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
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-Publisher FASB
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+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

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.

+ References

Reference 1: 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(22)(b))
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+ Details

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

- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
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+ Details

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

- Details

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- Details

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Balance Type:
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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Debt - Revolving Credit Facility (Details)			3 Months Ended
Debt - Revolving Credit Facility (Details)	Aug. 06, 2024 USD ($)	Nov. 01, 2021 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2024 USD ($)	Apr. 08, 2024 USD ($)
2024 Revolver \| Line of Credit
Line of Credit Facility [Line Items]
Maximum borrowing capacity	$ 150,000,000
Outstanding borrowings				$ 0
Letters of credit outstanding, amount				99,300,000
Revolving Credit Facility \| The Revolver \| Line of Credit
Line of Credit Facility [Line Items]
Maximum borrowing capacity		$ 200,000,000
Commitment fee		0.55%
Revolving Credit Facility \| The Revolver \| London Interbank Offered Rate (LIBOR) Or Euro Interbank Offered Rate (EURIBOR) \| Line of Credit
Line of Credit Facility [Line Items]
Interest rate		3.00%
Revolving Credit Facility \| The Revolver \| Base Rate \| Line of Credit
Line of Credit Facility [Line Items]
Interest rate		2.00%
Revolving Credit Facility \| The Revolver \| Daily Simple RFR \| Line of Credit
Line of Credit Facility [Line Items]
Interest rate		3.1193%
Revolving Credit Facility \| Asset-Based Lending Facility \| Line of Credit
Line of Credit Facility [Line Items]
Commitment fee			0.45%
Borrowing base qualified cash threshold			$ 100,000,000.0
Covenant excess availability percentage			12.50%
Borrowing base amount			$ 200,000,000
Covenant, line cap, one			25,000,000
Line cap additional threshold amount			$ 50,000,000
Total liquidity, line cap, threshold percentage			20.00%
Additional threshold amount			$ 64,000,000
Covenant relief excess availability percentage			10.00%
Commitment fee threshold percent			50.00%
Revolving Credit Facility \| Asset-Based Lending Facility \| Line of Credit \| Minimum
Line of Credit Facility [Line Items]
Commitment fee			0.375%
Line cap additional threshold percent			$ 15,000,000
Revolving Credit Facility \| Asset-Based Lending Facility \| Line of Credit \| Maximum
Line of Credit Facility [Line Items]
Commitment fee			0.45%
Revolving Credit Facility \| Asset-Based Lending Facility \| Base Rate \| Line of Credit \| Minimum
Line of Credit Facility [Line Items]
Interest rate			1.00%
Revolving Credit Facility \| Asset-Based Lending Facility \| Base Rate \| Line of Credit \| Maximum
Line of Credit Facility [Line Items]
Interest rate			1.50%
Revolving Credit Facility \| Asset-Based Lending Facility \| Prime Rate \| Line of Credit \| Minimum
Line of Credit Facility [Line Items]
Interest rate			1.00%
Revolving Credit Facility \| Asset-Based Lending Facility \| Prime Rate \| Line of Credit \| Maximum
Line of Credit Facility [Line Items]
Interest rate			1.50%
Revolving Credit Facility \| Asset-Based Lending Facility \| Adjust Term SOFR Rate, Adjusted EURIBOR Rate, Or Adjusted Term CORRA Rate \| Line of Credit \| Minimum
Line of Credit Facility [Line Items]
Interest rate			2.00%
Revolving Credit Facility \| Asset-Based Lending Facility \| Adjust Term SOFR Rate, Adjusted EURIBOR Rate, Or Adjusted Term CORRA Rate \| Line of Credit \| Maximum
Line of Credit Facility [Line Items]
Interest rate			2.50%
Revolving Credit Facility \| Asset-Based Lending Facility \| Line of Credit
Line of Credit Facility [Line Items]
Maximum borrowing capacity					$ 400,000,000
Revolving Credit Facility \| 2024 Revolver \| Line of Credit
Line of Credit Facility [Line Items]
Maximum borrowing capacity	$ 500,000,000
Leverage ratio	3.50
Revolving Credit Facility \| 2024 Revolver \| Line of Credit \| Minimum
Line of Credit Facility [Line Items]
Line cap additional threshold amount	$ 100,000,000
Revolving Credit Facility \| 2024 Revolver \| Line of Credit \| Maximum
Line of Credit Facility [Line Items]
Line cap additional threshold amount	$ 150,000,000
Revolving Credit Facility \| 2024 Revolver \| Base Rate \| Line of Credit
Line of Credit Facility [Line Items]
Interest rate	2.00%
Revolving Credit Facility \| 2024 Revolver \| Daily Simple RFR \| Line of Credit
Line of Credit Facility [Line Items]
Interest rate	3.00%
Revolving Credit Facility \| 2024 Revolver \| Adjust Term SOFR Rate, Adjusted EURIBOR Rate, Or Adjusted Term CORRA Rate \| Line of Credit
Line of Credit Facility [Line Items]
Interest rate	3.00%
Letter of Credit \| The Revolver \| Line of Credit
Line of Credit Facility [Line Items]
Letter of credit participation fee		2.75%
Letter of Credit \| Asset-Based Lending Facility \| Line of Credit
Line of Credit Facility [Line Items]
Maximum borrowing capacity			$ 200,000,000
Letter of Credit \| 2024 Revolver \| Line of Credit
Line of Credit Facility [Line Items]
Maximum borrowing capacity	$ 500,000,000
Letter of credit participation fee	0.50%
Letter of Credit Issued \| 2024 Revolver \| Line of Credit
Line of Credit Facility [Line Items]
Long term debt				$ 400,700,000