Dividends and earnings (loss) per share (Details) - $ / shares	3 Months Ended	9 Months Ended
Jul. 31, 2021	Jul. 31, 2020	Jul. 31, 2021	Jul. 31, 2020
Earnings per share:
Dividend per share	$ 0.05		$ 0.05
Average dilutive shares outstanding	4,000		2,000	3,000
Impact of Earnings per share				$ 0.01
Anti-dulutive shares excluded from the computation of diluted earnings per share	268,000	311,000	268,000	268,000

Impact of Earnings per share.

No definition available.

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Namespace Prefix:	frevsob_
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Balance Type:	na
Period Type:	duration

- Definition

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=124432515&loc=d3e3550-109257

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

The per share amount of a dividend declared, but not paid, as of the financial reporting date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=123431023&loc=d3e4304-108586

+ Details

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Balance Type:	na
Period Type:	instant

- References

No definition available.

+ Details

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

- Definition

The sum of dilutive potential common shares or units used in the calculation of the diluted per-share or per-unit computation.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=124432515&loc=d3e3550-109257

+ Details

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Balance Type:	na
Period Type:	duration