Mortgages payable and credit line (Schedule of Debt) (Details) - USD ($) $ in Thousands	Oct. 31, 2021	Oct. 31, 2020
Debt Instrument [Line Items]
Unamortized debt issuance costs	$ 1,400	$ 1,810
Total mortgages, notes payable and credit line	301,276	307,240
Mortgages [Member]
Debt Instrument [Line Items]
Fixed rate mortgage loans	138,568	141,945
Unamortized debt issuance costs	974	1,190
Mortgages [Member] \| Rockaway, NJ Mortgage [Member]
Debt Instrument [Line Items]
Fixed rate mortgage loans	14,453	15,050
Unamortized debt issuance costs	50	23
Mortgages [Member] \| Westwood, NJ #2 [Member]
Debt Instrument [Line Items]
Fixed rate mortgage loans	18,001	18,695
Unamortized debt issuance costs	39	71
Mortgages [Member] \| Wayne, NJ Mortgage [Member] \| Berdan Court, LLC [Member]
Debt Instrument [Line Items]
Fixed rate mortgage loans	28,815	28,815
Unamortized debt issuance costs	379	427
Mortgages [Member] \| River Edge, NJ First Mortgage [Member]
Debt Instrument [Line Items]
Fixed rate mortgage loans	9,545	9,789
Unamortized debt issuance costs	36	53
Mortgages [Member] \| Red Bank, NJ Mortgage [Member]
Debt Instrument [Line Items]
Fixed rate mortgage loans	11,971	12,181
Unamortized debt issuance costs	93	108
Mortgages [Member] \| Wayne, PSC LLC [Member]
Debt Instrument [Line Items]
Fixed rate mortgage loans	22,588	23,336
Unamortized debt issuance costs	172	205
Mortgages [Member] \| Damascus, MD [Member]
Debt Instrument [Line Items]
Fixed rate mortgage loans	18,274	18,824
Unamortized debt issuance costs	101	166
Mortgages [Member] \| Middletown, NY Mortgage [Member]
Debt Instrument [Line Items]
Fixed rate mortgage loans	14,921	15,255
Unamortized debt issuance costs	104	137
Notes Payable, Other Payables [Member]
Debt Instrument [Line Items]
Unamortized debt issuance costs	426	620
Variable rate mortgage loans and credit line	162,708	165,295
Notes Payable, Other Payables [Member] \| Westwood, NJ [Member]
Debt Instrument [Line Items]
Unamortized debt issuance costs	220	460
Variable rate mortgage loan	25,000	25,000
Notes Payable, Other Payables [Member] \| Frederick, MD [Member]
Debt Instrument [Line Items]
Unamortized debt issuance costs	30
Variable rate mortgage loan	21,188	21,775
Notes Payable, Other Payables [Member] \| Baltimore, MD [Member]
Debt Instrument [Line Items]
Unamortized debt issuance costs	105	160
Variable rate mortgage loan	116,520	118,520
Provident Bank [Member]
Debt Instrument [Line Items]
Unamortized debt issuance costs	71
Line of credit

Variable rate mortgage loan.

No definition available.

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

- Definition

Variable rate mortgage loans and credit line.

+ References

No definition available.

+ Details

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

- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
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-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
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-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

+ Details

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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

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- Definition

Amount, before accumulated amortization, of debt issuance costs classified as noncurrent. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

+ Details

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Balance Type:	debit
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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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-Name Accounting Standards Codification
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+ Details

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- 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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