Remaining balance inclusive of the transaction costs.

No definition available.

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Namespace Prefix:	frevsob_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

Amount of direct costs of the business combination including legal, accounting, and other costs incurred to consummate the business acquisition.

+ References

No definition available.

+ Details

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

- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

+ Details

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Period Type:	instant

- Definition

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 23
-URI http://asc.fasb.org/extlink&oid=84229725&loc=d3e1043-128460

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

The cash inflow associated with the amount received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3179-108585

+ Details

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

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

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- Details

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Balance Type:
Period Type:

- Details

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Data Type:	na
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- Details

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- Details

Name:	us-gaap_BusinessAcquisitionAxis=frevsob_HammelGardensPropertyMember
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Property acquisition (Details) - USD ($)		6 Months Ended
Property acquisition (Details) - USD ($)	Dec. 07, 2017	Apr. 30, 2018
Real Estate [Line Items]
Transaction costs		$ 19,500,000
Building [Member]
Real Estate [Line Items]
Transaction costs		10,700,000
Land [Member]
Real Estate [Line Items]
Transaction costs		8,800,000
Provident Bank [Member]
Real Estate [Line Items]
Remaining balance (inclusive of the transaction costs)		12,350,000
Station Place on Monmouth, LLC [Member]
Real Estate [Line Items]
Percentage of acquisition	100.00%
Regency acquisition costs	$ 19,542,000
Transaction costs		542,000
Hammel Gardens Property [Member]
Real Estate [Line Items]
Net proceed from sales		$ 7,000,000