Annual debt service savings.

No definition available.

Name:	frevsob_AnnualDebtServiceSavings
Namespace Prefix:	frevsob_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Fixed interest rate on old loan.

+ References

No definition available.

+ Details

Name:	frevsob_DebtInstrumentInterestRateStatedPercentagePreviousLoan
Namespace Prefix:	frevsob_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The new face (par) amount of debt instrument.

+ References

No definition available.

+ Details

Name:	frevsob_DebtInstrumentNewFaceAmount
Namespace Prefix:	frevsob_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

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+ Details

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

- 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

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Date when the debt instrument is scheduled to be fully repaid, in YYYY-MM-DD format.

+ References

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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

+ References

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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 portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a set, unchanging rate.

+ References

No definition available.

+ Details

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

- Definition

Amount of cash outflow for costs that are essential to originate the lease and would not otherwise have been incurred without the lease agreement. Amount includes, but is not limited to, cash outflows to evaluate the lessee's credit condition, guarantees, and collateral and cash outflows for costs incurred in negotiating, processing, and executing the lease agreement.

+ References

No definition available.

+ Details

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

- Details

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Balance Type:
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- Details

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- Details

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Balance Type:
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Mortgage financings and line of credit (Details) - USD ($)	1 Months Ended	6 Months Ended
	Dec. 30, 2021	Apr. 30, 2022	Apr. 30, 2021	Oct. 31, 2021
Debt Instrument [Line Items]
Available to draw		$ 88,000	$ 143,000
Fixed interest rate on old loan		5.00%
Line of Credit, available		$ 13,000,000		$ 13,000,000
Loan amount		25,000,000
People's United Bank [Member]
Debt Instrument [Line Items]
Loan amount		$ 22,200,000
Line of Credit [Member]
Debt Instrument [Line Items]
Maturity date of loan		Oct. 31, 2023
Line of Credit, available		$ 13,000,000
Basis points, interest rate		3.75%
FREIT Maryland [Member]
Debt Instrument [Line Items]
Fixed rate mortgage loans	$ 14,400,000
Maturity date of loan	Feb. 01, 2022
Loan amount, new	$ 7,500,000
Available to draw	7,500,000
Annual debt service savings	$ 1,173,000
FREIT Maryland [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Fixed interest rate on old loan	2.85%
FREIT Maryland [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Fixed interest rate on old loan	5.37%