XML 47 R39.htm IDEA: XBRL DOCUMENT
v3.25.3

Summary of Significant Accounting Policies - Additional Information (Details) | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Sep. 30, 2025 USD ($) | Sep. 30, 2024 USD ($) | Sep. 30, 2025 USD ($) Bitcoin | Sep. 30, 2024 USD ($) | Dec. 31, 2024 USD ($) Bitcoin
Accounting Policies [Abstract] |  |  |  |  |
Segment Reporting, CODM, Profit (Loss) Measure, How Used, Description |  |  | The primary financial measure used by the CODM to evaluate performance is operating income (loss) as shown on the statements of operations. Segment expenses and other segment items are provided to the CODM on the same basis as disclosed in the statements of operations. |  |
Segment Reporting, CODM, Individual Title and Position or Group Name [Extensible Enumeration] |  |  | srt:ChiefExecutiveOfficerMember |  |
Amortization expense on capitalized software development costs | $ 200,000 | $ 100,000 | $ 400,000 | $ 200,000 |
Amortization expense write-offs | 100,000 | 0 | $ 100,000 | 0 |
Notional amount of customer rewards liability outstanding | Bitcoin |  |  | 81 |  | 92
Derivative instruments within customer rewards liability | 9,300,000 |  | $ 9,300,000 |  | $ 8,600,000
Gain (loss) on remeasurement of derivative liability | $ (500,000) | $ 100,000 | $ (1,500,000) | $ (2,300,000) |

X
- Definition Amortization expense writeoff. + References No definition available. + Details
Name: | fld_AmortizationExpenseWriteoff
Namespace Prefix: | fld_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Gain loss on remeasurement of derivative liability. + References No definition available. + Details
Name: | fld_GainLossOnRemeasurementOfDerivativeLiability
Namespace Prefix: | fld_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Notional amount of customer rewards liability outstanding. + References No definition available. + Details
Name: | fld_NotionalAmountOfCustomerRewardsLiabilityOutstanding
Namespace Prefix: | fld_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

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

X
- Definition Amount of expense for amortization of capitalized computer software costs. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 985 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481283/985-20-50-2 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 985 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (b)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481283/985-20-50-1 + Details
Name: | us-gaap_CapitalizedComputerSoftwareAmortization1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (bbb)(2)(i) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (bbb)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (bbb)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 7A -Publisher FASB -URI https://asc.fasb.org/1943274/2147480434/815-10-50-7A Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 825 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 11 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482907/825-10-50-11 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Topic 825 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 11 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482907/825-10-50-11 Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Topic 825 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 10 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482907/825-10-50-10 Reference 8: http://www.xbrl.org/2003/role/exampleRef -Topic 210 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 22 -Publisher FASB -URI https://asc.fasb.org/1943274/2147483444/210-20-55-22 Reference 9: http://www.xbrl.org/2003/role/exampleRef -Topic 210 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 21 -Publisher FASB -URI https://asc.fasb.org/1943274/2147483444/210-20-55-21 Reference 10: http://www.xbrl.org/2003/role/exampleRef -Topic 210 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 20 -Publisher FASB -URI https://asc.fasb.org/1943274/2147483444/210-20-55-20 Reference 11: http://www.xbrl.org/2003/role/exampleRef -Topic 210 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 15 -Publisher FASB -URI https://asc.fasb.org/1943274/2147483444/210-20-55-15 Reference 12: http://www.xbrl.org/2003/role/disclosureRef -Topic 210 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 10 -Publisher FASB -URI https://asc.fasb.org/1943274/2147483444/210-20-55-10 Reference 13: http://www.xbrl.org/2003/role/disclosureRef -Topic 210 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483466/210-20-50-3 Reference 14: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 Reference 15: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 Reference 16: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-3 Reference 17: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 210 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (e) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478795/946-210-50-6 Reference 18: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 210 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (a)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478795/946-210-50-6 Reference 19: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 210 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (a)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478795/946-210-50-6 Reference 20: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 210 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (a)(4) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478795/946-210-50-6 Reference 21: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 210 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (a)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478795/946-210-50-1 Reference 22: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 210 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (b)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478795/946-210-50-1 Reference 23: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 210 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (b)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478795/946-210-50-1 Reference 24: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 210 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (c)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478795/946-210-50-1 Reference 25: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 210 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (f) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478795/946-210-50-6 Reference 26: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 946 -SubTopic 210 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (a)(3) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478795/946-210-50-6 Reference 27: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.6-04(9)(e)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479170/946-210-S99-1 Reference 28: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 320 -Name Accounting Standards Codification -Section S99 -Paragraph 5C -Subparagraph (SX 210.12-13C(Column H)(Footnote 7)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477271/946-320-S99-5C Reference 29: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.6-04(9)(b)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479170/946-210-S99-1 Reference 30: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.6-04(9)(d)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479170/946-210-S99-1 Reference 31: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 320 -Name Accounting Standards Codification -Section S99 -Paragraph 5 -Subparagraph (SX 210.12-13(Column G)(Footnote 8)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477271/946-320-S99-5 Reference 32: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 320 -Name Accounting Standards Codification -Section S99 -Paragraph 5C -Subparagraph (SX 210.12-13C(Column H)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477271/946-320-S99-5C Reference 33: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 320 -Name Accounting Standards Codification -Section S99 -Paragraph 5 -Subparagraph (SX 210.12-13(Column G)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477271/946-320-S99-5 Reference 34: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 320 -Name Accounting Standards Codification -Section S99 -Paragraph 5A -Subparagraph (SX 210.12-13A(Column E)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477271/946-320-S99-5A Reference 35: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 320 -Name Accounting Standards Codification -Section S99 -Paragraph 5B -Subparagraph (SX 210.12-13B(Column E)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477271/946-320-S99-5B Reference 36: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 320 -Name Accounting Standards Codification -Section S99 -Paragraph 5B -Subparagraph (SX 210.12-13B(Column E)(Footnote 4)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477271/946-320-S99-5B + Details
Name: | us-gaap_DerivativeLiabilities
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Indicates title and position of individual or name of group identified as chief operating decision maker (CODM) for segment reporting. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 280 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 54 -Subparagraph (f) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482785/280-10-55-54 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 280 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 47 -Subparagraph (e) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482785/280-10-55-47 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 280 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 21 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482810/280-10-50-21 + Details
Name: | us-gaap_SegmentReportingCodmIndividualTitleAndPositionOrGroupOrCommitteeNameExtensibleEnumeration
Namespace Prefix: | us-gaap_
Data Type: | enum2:enumerationSetItemType
Balance Type: | na
Period Type: | duration

X
- Definition Description of how chief operating decision maker (CODM) uses reported segment profit (loss) measure to assess performance and allocate resource. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 280 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 47 -Subparagraph (bb) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482785/280-10-55-47 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 280 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 54 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482785/280-10-55-54 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 280 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 29 -Subparagraph (f) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482810/280-10-50-29 + Details
Name: | us-gaap_SegmentReportingCodmProfitLossMeasureHowUsedDescription
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration