Management agreement, fees and transactions with related party (Details) - USD ($)		6 Months Ended	12 Months Ended
	Oct. 31, 2006	May. 07, 2008	Oct. 31, 2015	Oct. 31, 2014	Oct. 31, 2013
Related Party Transaction [Line Items]
Asset management fees			$ 2,000,000	$ 1,968,000	$ 1,849,000
Total construction financing, including other members			$ 14,460,000
Secured loans receivable to noncontrolling interest				(2,128,000)
Amount of the capital call			$ 8,700,000
Payment of capital call			8,700,000
Trustee fee expense			$ 781,000
S and A Commercial Associates Limited Partnership ("S and A") [Member]
Related Party Transaction [Line Items]
Ownership by parent (percentage)			65.00%
Damascus Centre, LLC [Member]
Related Party Transaction [Line Items]
Ownership by parent (percentage)			70.00%
Ownership by noncontrolling owners (percentage)			30.00%
Sale of interest	$ 3,224,000
Sale of interest, amount financed	$ 1,451,000
Grande Rotunda, LLC [Member]
Related Party Transaction [Line Items]
Aggregate outstanding principal balance			$ 5,451,000	5,451,000
Accrued but unpaid interest			$ 732,000	595,000
Ownership by parent (percentage)			60.00%
Ownership by noncontrolling owners (percentage)			40.00%
Managing Agent Hekemian & Co [Member]
Related Party Transaction [Line Items]
Asset management fees			$ 1,899,000	1,866,000	$ 1,747,000
Leasing commissions and reimbursement of operating expenses			465,000	673,000	339,000
Leasing commissions			396,000
Insurance commissions			166,000	133,000	121,000
Sales commissions				880,000	185,000
Other fees - refinancing					239,000
Maximum advances to employees		$ 2,000,000	4,000,000
Accounts Payable			163,000	171,000
Robert S. Hekemian [Member]
Related Party Transaction [Line Items]
Trustee fee expense			538,000	642,000	586,000
Robert S. Hekemian, Jr. [Member]
Related Party Transaction [Line Items]
Trustee fee expense			65,000	46,000	40,000
Rotunda 100 [Member]
Related Party Transaction [Line Items]
Secured loans receivable to noncontrolling interest			$ (2,100,000)
Basis points, interest rate			2.25%
Amount of the capital call			$ 5,800,000
Payment of capital call			5,800,000
Advance to affiliate			3,700,000
Fee amount			$ 1,400,000
Affiliated Entity [Member]
Related Party Transaction [Line Items]
Development fee (as percentage)			6.375%
Development fees paid				3,000,000
Fee, monthly amount during design phase					500,000
Fee, to be paid on issuance of certificate of occupancy			$ 900,000
Affiliated Entity 1 [Member]
Related Party Transaction [Line Items]
Development fees paid			1,000,000	1,000,000
Redevelopment fees			1,546,000	1,998,000	1,823,000
Construction and development costs					$ 1,400,000
Development fees included in accounts payable			$ 900,000	$ 900,000