Contingent Liabilities (Details) - USD ($) $ in Thousands	1 Months Ended
Dec. 31, 2023	Sep. 30, 2025
Guarantor Obligations [Line Items]
Outstanding letters of credit		$ 449
Guarantee Obligations
Guarantor Obligations [Line Items]
Interest carry cost	$ 110,000
Value of guarantee	$ 1,500
Interest savings (as percent)	0.80%
Debt instrument, term (in months)	36 months

Value Of Guarantee

No definition available.

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Namespace Prefix:	frph_
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Balance Type:	credit
Period Type:	instant

- Definition

Incremental percentage increase (decrease) in the stated rate on a debt instrument.

+ References

No definition available.

+ Details

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- 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 460
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482425/460-10-50-4

+ Details

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- Definition

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 460
-SubTopic 10
-Name Accounting Standards Codification
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-Paragraph 4
-Subparagraph (b)(1)
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+ Details

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Period Type:	instant

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 944
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+ Details

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- Details

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