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Management agreement, fees and transactions with related party (Details) - USD ($)	1 Months Ended	3 Months Ended			12 Months Ended
	Feb. 28, 2018	Jan. 31, 2019	Oct. 31, 2018	Jan. 31, 2018	Oct. 30, 2013
Related Party Transaction [Line Items]
Asset management fees		$ 637,000		$ 611,000
Brokerage commissions		15,000		0
Secured loans receivable		4,000,000	$ 4,000,000
Due to affiliate		$ 5,488,000	5,417,000
Minimum [Member]
Related Party Transaction [Line Items]
Asset management fees percentage rate		4.00%
Maximum [Member]
Related Party Transaction [Line Items]
Asset management fees percentage rate		5.00%
Damascus Centre [Member]
Related Party Transaction [Line Items]
Secured notes outstanding			1,870,000
Principal amount on notes			1,451,000
Accrued interest payable			419,000
Unpaid accrued interest		$ 909,000	862,000
Grande Rotunda, LLC [Member]
Related Party Transaction [Line Items]
Ownership by noncontrolling owners (percentage)		40.00%
Ownership by parent (percentage)		60.00%
Due to affiliate		$ 5,500,000
Damascus Centre, LLC [Member]
Related Party Transaction [Line Items]
Ownership by noncontrolling owners (percentage)		30.00%
Ownership by parent (percentage)		70.00%
Grande Rotunda, LLC [Member]
Related Party Transaction [Line Items]
Due to affiliate			$ 5,400,000
Managing Agent Hekemian & Co [Member]
Related Party Transaction [Line Items]
Asset management fees		$ 619,000		575,000
Leasing commissions and reimbursement of operating expenses		133,000		141,000
Sales commissions				522,500
Insurance commissions		29,000		31,000
Additional services		0		762,500
Brokerage commissions		240,000
Grande Rotunda LLC [Member]
Related Party Transaction [Line Items]
Fee amount	$ 900,000	1,400,000		45,000	$ 500,000
Affiliated Entity 1 [Member]
Related Party Transaction [Line Items]
Development fees included in accounts payable	900,000
Hekemian and Resources [Member]
Related Party Transaction [Line Items]
Fee amount	$ 900,000
Robert S. Hekemian [Member]
Related Party Transaction [Line Items]
Trustee fees and related interest payable in stock units		60,000		136,000
Consulting fee per month		5,000
Consulting fee quarterly installments		15,000
Robert S. Hekemian, Jr. [Member]
Related Party Transaction [Line Items]
Trustee fees and related interest payable in stock units		95,000		14,000
David Hekemian [Member]
Related Party Transaction [Line Items]
Trustee fees and related interest payable in stock units		$ 12,000		$ 0