LEASES - Summary of Changes in Lease Receivables (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2024	Dec. 31, 2023
Sales-type and Direct Financing Leases, Lease Receivable [Roll Forward]
Balance, beginning of period	$ 7,953	$ 9,421
Interest	516	2,342
Lease payments transferred to accounts receivable	(990)	(3,810)
Balance, end of period	7,479	7,953
Less current portion	(4,035)	(3,990)
Long-term lease receivables	$ 3,444	$ 3,963

Lease receivables Interest during the period.

No definition available.

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

- Definition

Lease Receivables Lease Payments Transferred To Accounts Receivable

+ References

No definition available.

+ Details

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

- Definition

Sales-type and Direct Financing Leases, Lease Receivable

+ References

No definition available.

+ Details

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Namespace Prefix:	ffntf_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

This item represents the current receivable for an incentive or inducement contractually stipulated between parties to a lease whereby the lessor has committed to provide the entity (lessee) with a cash payment as inducement to enter the lease. The receivable is due within one year. For classified balance sheets, this element represents the current amount receivable, that is amounts expected to be collected within one year or the normal operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(8))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

+ Details

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

- Definition

Noncurrent portion of receivables for an incentive or inducement contractually stipulated between parties to a lease whereby the lessor has committed to provide the entity (lessee) with a cash payment as inducement to enter the lease.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(17))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

+ Details

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

- Definition

Present value of lease payments not yet received by lessor and amount expected to be derived from underlying asset, following end of lease term guaranteed by lessee or other third party unrelated to lessor, from sales-type and direct financing leases.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479773/842-30-50-6

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479773/842-30-50-10

+ Details

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