Management agreement, fees and transactions with related party (Details) - USD ($)		1 Months Ended	8 Months Ended	12 Months Ended
	May 08, 2008	Feb. 28, 2018	Oct. 31, 2020	Oct. 31, 2020	Oct. 31, 2019	Oct. 31, 2018	Oct. 31, 2017	Oct. 31, 2016
Related Party Transaction [Line Items]
Asset management fees				$ 2,251,000	$ 2,603,000	$ 2,547,000
Sale/Acquisition commissions						522,500
Insurance commissions			$ 26,000
Due to affiliate			5,921,000	5,921,000	5,705,000
Secured loans receivable			5,194,000	5,194,000	5,053,000
Commissions related to loan financing				144,075
Letter of Credit [Member]
Related Party Transaction [Line Items]
Sale/Acquisition commissions						32,500
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
Grande Rotunda, LLC [Member]
Related Party Transaction [Line Items]
Aggregate outstanding principal balance			4,000,000	4,000,000	4,000,000
Accrued but unpaid interest			$ 1,194,000	$ 1,194,000	1,053,000
Ownership by parent (percentage)			60.00%	60.00%
Ownership by noncontrolling owners (percentage)			40.00%	40.00%
Due to affiliate			$ 5,900,000	$ 5,900,000	5,700,000
Managing Agent Hekemian & Co [Member]
Related Party Transaction [Line Items]
Asset management fees				2,201,000	2,549,000	2,438,000
Leasing commissions and reimbursement of operating expenses				982,000	762,000	742,000
Insurance commissions				190,000	196,000	178,000
Maximum advances to employees	$ 2,000,000			4,000,000
Accounts Payable			$ 182,000	182,000	219,000
Rotunda 100 [Member]
Related Party Transaction [Line Items]
Fee amount				1,400,000
Affiliated Entity 1 [Member]
Related Party Transaction [Line Items]
Development fees included in accounts payable							$ 900,000	$ 900,000
Consulting services expense				125,000	275,000	1,195,000
Berdan Court, LLC [Member]
Related Party Transaction [Line Items]
Sale/Acquisition commissions					131,250
Grande Rotunda, LLC [Member]
Related Party Transaction [Line Items]
Sale/Acquisition commissions						400,000
Fee amount		$ 900,000
Fee resources amount						900,000
Pierre Towers, LLC [Member]
Related Party Transaction [Line Items]
Sale/Acquisition commissions						240,000
Robert S. Hekemian [Member]
Related Party Transaction [Line Items]
Trustee fee expense				21,000	214,000	365,000
Consulting services expense				8,000	60,000	34,200
Consulting fee per month				5,000
Consulting fee quarterly installments				15,000
Robert S. Hekemian, Jr. [Member]
Related Party Transaction [Line Items]
Trustee fee expense				508,000	381,000	235,000
Allan Tubin [Member]
Related Party Transaction [Line Items]
Trustee fee expense				26,000	22,000	0
David Hekemian [Member]
Related Party Transaction [Line Items]
Trustee fee expense				$ 50,000	$ 56,000	$ 26,000