Interest rate cap and swap contracts (Details) - USD ($)	3 Months Ended		9 Months Ended
	Jul. 31, 2021	Jul. 31, 2020	Jul. 31, 2021	Jul. 31, 2020	Oct. 31, 2020
Derivative [Line Items]
Interest rate swap contract liability	$ 3,483,000		$ 3,483,000		$ 4,924,000
Net unrealized gain (loss) on interest rate swap contracts	(234,000)	$ (272,000)	1,441,000	$ (3,644,000)
Damascus Centre Swap [Member]
Derivative [Line Items]
Interest rate swap contract liability	391,000		391,000		610,000
Wayne PSC swap [Member]
Derivative [Line Items]
Interest rate swap contract liability	802,000		802,000		1,260,000
Regency Swap [Member]
Derivative [Line Items]
Interest rate swap contract liability	1,030,000		1,030,000		1,385,000
Station Place [Member]
Derivative [Line Items]
Interest rate swap contract liability	1,260,000		1,260,000		1,669,000
Grande Rotunda LLC [Member]
Derivative [Line Items]
Interest rate swap contract liability	$ 0		$ 0		$ 0