Extended date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

No definition available.

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Namespace Prefix:	frevsob_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Fixed interest rate on old loan.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Available amount of debt instrument at time of issuance.

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

The new face (par) amount of debt instrument.

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Deferred loan payments.

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Interest rate percentage.

+ References

No definition available.

+ Details

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Namespace Prefix:	frevsob_
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Balance Type:	na
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- Definition

Maturity date of interest rate cap.

+ References

No definition available.

+ Details

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Data Type:	xbrli:dateItemType
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Period Type:	duration

- 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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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
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-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

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

- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 6
-Subparagraph (a)
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-Name Accounting Standards Codification
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-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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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

No definition available.

+ Details

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Period Type:	duration

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(2))
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-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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

- Definition

Amount of the required periodic payments including both interest and principal payments.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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-Section 50
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-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823

+ Details

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

- Definition

Amount of the required periodic payments applied to principal.

+ References

+ Details

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

- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The amount of expense provided in the period for legal costs incurred on or before the balance sheet date pertaining to resolved, pending or threatened litigation, including arbitration and mediation proceedings.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.3)
-URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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

+ Details

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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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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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Balance Type:	credit
Period Type:	duration

- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

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Mortgage financings and line of credit (Details) - USD ($)						1 Months Ended	3 Months Ended	12 Months Ended
	Mar. 05, 2021	Sep. 30, 2020	Apr. 03, 2019	Feb. 07, 2018	Feb. 07, 2018	Feb. 28, 2020	Jan. 31, 2021	Oct. 31, 2020	Jan. 31, 2020
Debt Instrument [Line Items]
Deferred loan payments							$ 1,013,000
Repayments Of Loan							162,000	$ 162,000
Legal fees							481,000
Westwood Hills Property [Member]
Debt Instrument [Line Items]
Fixed rate mortgage loans		$ 19,200,000
Loan amount, new									$ 25,000,000
Basis points, interest rate		400.00%
Interest rate									4.15%
Membership interest percentage		40.00%
Maturity date of loan		Oct. 01, 2022
Available to draw		$ 25,000,000
Legal fees		250,000
Westwood Hills Property [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Fixed rate mortgage loans		$ 2,200,000
Fixed interest rate on old loan		4.15%
Westwood Hills Property [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Fixed rate mortgage loans		$ 5,600,000
Fixed interest rate on old loan		4.62%
M&T Bank [Member]
Debt Instrument [Line Items]
Loan amount			$ 22,500,000				$ 21,600,000
Basis points, interest rate			240.00%				255.00%
Interest rate cap							2.59%
Maturity date of loan			May 01, 2020
Extended maturity date of loan			Nov. 01, 2020				Jan. 31, 2023
Maturity date of interest rate cap							Jan. 31, 2022
Monthly payment of loan			$ 47,250				$ 49,250
Wells Fargo Bank [Member]
Debt Instrument [Line Items]
Fixed rate mortgage loans				$ 500,000	$ 500,000
Loan amount				118,500,000	118,500,000
Principal payments per quater					750,000
Aareal Capital Corporation [Member]
Debt Instrument [Line Items]
Loan amount				$ 118,500,000	$ 118,500,000		$ 118,500,000
Basis points, interest rate				285.00%
Interest rate cap				3.00%	3.00%		2.99%
Maturity date of loan				Feb. 06, 2021
Available to draw				$ 3,380,000
Monthly payment of loan				$ 121,900,000
Aareal Capital Corporation [Member] \| Subsequent Event [Member]
Debt Instrument [Line Items]
Loan amount	$ 118,500,000
Interest rate cap	3.00%
Maturity date of loan	Feb. 06, 2022
Grande Rotunda LLC [Member]
Debt Instrument [Line Items]
Loan amount available						$ 121,900,000
Interest rate cap						3.00%
Maturity date of interest rate cap						Mar. 05, 2020
Provident Bank [Member]
Debt Instrument [Line Items]
Loan amount									$ 13,000,000
Basis points, interest rate							25.00%
Interest rate cap									3.75%
Line of credit, maximum borrowing capacity									$ 13,000,000