Segment information (Details) $ in Thousands	3 Months Ended	6 Months Ended
Apr. 30, 2018 USD ($) properties	Apr. 30, 2017 USD ($)	Apr. 30, 2018 USD ($) properties segments	Apr. 30, 2017 USD ($) segments
Reportable Segments
Real estate rental revenue	$ 14,325	$ 12,664	$ 28,519	$ 25,263
Real estate operating expenses	8,555	10,554	18,572	19,677
Operating income	5,770	2,110	9,947	5,586
Reconciliation to condensed consolidated net income (loss) attributable to common equity:
Segment NOI	9,135	5,838	16,478	12,230
Deferred rents - straight lining	75	173	173	311
Lease termination fee		(620)		(620)
Investment income	57	45	112	91
Unrealized gain on interest rate cap contract	19		19
General and administrative expenses	(639)	(633)	(1,192)	(1,157)
Depreciation	(2,801)	(2,648)	(5,512)	(5,178)
Financing costs	(4,419)	(3,856)	(9,571)	(7,722)
Net income (loss)	1,427	(1,701)	507	(2,045)
Net (income) loss attributable to noncontrolling interests in subsidiaries	(312)	1,002	251	1,409
Net income (loss) attributable to common equity	1,115	(699)	$ 758	$ (636)
Number of reportable segments \| segments			2	2
Operating Segments [Member]
Reportable Segments
Real estate rental revenue	14,250	12,491	$ 28,346	$ 24,952
Real estate operating expenses	5,115	6,653	11,868	12,722
Operating income	$ 9,135	5,838	$ 16,478	12,230
Commercial [Member]
Reconciliation to condensed consolidated net income (loss) attributable to common equity:
Number of properties \| properties	9		9
Commercial [Member] \| Operating Segments [Member]
Reportable Segments
Real estate rental revenue	$ 6,263	5,996	$ 12,566	12,070
Real estate operating expenses	2,964	2,950	6,001	5,835
Operating income	3,299	3,046	6,565	6,235
Residential [Member]
Reportable Segments
Recurring capital improvements	$ (127)	(179)	$ (238)	(379)
Reconciliation to condensed consolidated net income (loss) attributable to common equity:
Number of properties \| properties	8		8
Residential [Member] \| Operating Segments [Member]
Reportable Segments
Real estate rental revenue	$ 7,987	6,495	$ 15,780	12,882
Real estate operating expenses	2,151	3,703	5,867	6,887
Operating income	$ 5,836	$ 2,792	$ 9,913	$ 5,995

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