Mortgages payable and credit line (Schedule of Debt) (Details) - USD ($)	Oct. 31, 2019	Oct. 31, 2018	Jan. 08, 2018
Debt Instrument [Line Items]
Unamortized debt issuance costs	$ 2,886,000	$ 3,498,000
Total mortgages, notes payable and credit line	352,790,000	350,504,000
Mortgages [Member]
Debt Instrument [Line Items]
Fixed rate mortgage loans	212,070,000	209,274,000
Unamortized debt issuance costs	2,006,000	1,884,000
Variable rate mortgage loan	140,720,000	141,230,000
Mortgages [Member] \| Rockaway, NJ Mortgage [Member]
Debt Instrument [Line Items]
Fixed rate mortgage loans	15,615,000	16,152,000
Unamortized debt issuance costs	51,000	80,000
Mortgages [Member] \| Westwood, NJ #2 [Member]
Debt Instrument [Line Items]
Fixed rate mortgage loans	18,973,000	19,611,000
Unamortized debt issuance costs	103,000	134,000
Mortgages [Member] \| Patchogue, NY [Member]
Debt Instrument [Line Items]
Fixed rate mortgage loans		5,231,000
Unamortized debt issuance costs		15,000
Mortgages [Member] \| Wayne, NJ Mortgage [Member] \| Berdan Court, LLC [Member]
Debt Instrument [Line Items]
Fixed rate mortgage loans	28,815,000	17,334,000
Unamortized debt issuance costs	475,000	18,000
Mortgages [Member] \| River Edge, NJ First Mortgage [Member]
Debt Instrument [Line Items]
Fixed rate mortgage loans	10,021,000	10,243,000
Unamortized debt issuance costs	70,000	87,000
Mortgages [Member] \| Red Bank, NJ Mortgage [Member]
Debt Instrument [Line Items]
Fixed rate mortgage loans	12,350,000	12,350,000
Unamortized debt issuance costs	123,000	138,000
Mortgages [Member] \| Westwood, NJ #3 [Member]
Debt Instrument [Line Items]
Fixed rate mortgage loans	19,617,000	20,134,000
Unamortized debt issuance costs	34,000	67,000
Mortgages [Member] \| Wayne, PSC LLC [Member]
Debt Instrument [Line Items]
Fixed rate mortgage loans	23,737,000	24,432,000
Unamortized debt issuance costs	240,000	274,000
Mortgages [Member] \| Hackensack, NJ [Member] \| Pierre Towers, LLC [Member]
Debt Instrument [Line Items]
Fixed rate mortgage loans	48,000,000	48,000,000	$ 29,100,000
Unamortized debt issuance costs	509,000	572,000
Mortgages [Member] \| Damascus, MD [Member]
Debt Instrument [Line Items]
Fixed rate mortgage loans	19,354,000	19,865,000
Unamortized debt issuance costs	231,000	296,000
Mortgages [Member] \| Middletown, NY Mortgage [Member]
Debt Instrument [Line Items]
Fixed rate mortgage loans	15,588,000	15,922,000
Unamortized debt issuance costs	170,000	203,000
Notes Payable, Other Payables [Member]
Debt Instrument [Line Items]
Unamortized debt issuance costs	880,000	1,614,000
Variable rate mortgage loans and credit line	140,720,000	141,230,000
Notes Payable, Other Payables [Member] \| Frederick, MD [Member]
Debt Instrument [Line Items]
Unamortized debt issuance costs	28,000	70,000
Variable rate mortgage loan	22,200,000	22,710,000
Notes Payable, Other Payables [Member] \| Baltimore, MD [Member]
Debt Instrument [Line Items]
Unamortized debt issuance costs	800,000	1,439,000
Variable rate mortgage loan	118,520,000	118,520,000
Provident Bank [Member]
Debt Instrument [Line Items]
Unamortized debt issuance costs	52,000	105,000
Line of credit	$ 0	$ 0

Variable rate mortgage loan.

No definition available.

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- Definition

Variable rate mortgage loans and credit line.

+ References

No definition available.

+ Details

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- 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
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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.

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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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- 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

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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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