Segment information (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended											12 Months Ended
	Oct. 31, 2012		Jul. 31, 2012		Apr. 30, 2012		Jan. 31, 2012	Oct. 31, 2011	Jul. 31, 2011	Apr. 30, 2011	Jan. 31, 2011	Oct. 31, 2012	Oct. 31, 2011	Oct. 31, 2010
Segment Reporting Information [Line Items]
Real estate rental revenue												$ 36,877	$ 37,175	$ 36,793
Real estate operating expenses	9,424		11,682	[1]	10,818	[1]	9,335	9,281	8,919	9,103	9,313	29,728	25,265	25,721
Net operating income												15,746	17,781	17,394
Recurring capital improvements												2,114	1,343	1,855
Amortization of acquired above and below market value leases												2	25	30
Investment income												173	101	122
Depreciation												6,186	6,070	5,996
Deferred project cost write-off, net of income relating to early lease termination												3,726
Interest expense including amortization of deferred financing costs, and in 2010 a prepayment penalty of $2.1 million												(11,704)	(11,452)	(13,608)
Income from continuing operations	1,052		(1,014)		2,692		1,485	1,750	1,760	1,623	1,297	4,215	6,430	3,908
Income from discontinued operations	7,506	[2]	123		75		77	76	74	70	63	253	283	223
Gain on sale of discontinued operations (net of tax of $1,965)												7,528
Net income	8,558		(891)		2,767		1,562	1,826	1,834	1,693	1,360	11,996	6,713	4,131
Net (income) loss attributable to noncontrolling interests in subsidiaries	(120)		668		(824)		(369)	(292)	(329)	(373)	(341)	(645)	(1,335)	280
Net income attributable to common equity	8,438		(223)		1,943		1,193	1,534	1,505	1,320	1,019	11,351	5,378	4,411
Commercial
Segment Reporting Information [Line Items]
Real estate rental revenue												23,383	24,117	24,713
Real estate operating expenses												9,526	9,561	9,702
Net operating income												13,857	14,556	15,011
Residential
Segment Reporting Information [Line Items]
Real estate rental revenue												19,126	18,172	18,192
Real estate operating expenses												8,666	8,091	8,456
Net operating income												10,460	10,621	9,736
Recurring capital improvements												723	433	334
Total Reportable Segments
Segment Reporting Information [Line Items]
Real estate rental revenue												42,509	42,829	42,905
Real estate operating expenses												18,192	17,652	18,158
Net operating income												24,317	25,177	24,747
Deferred rents - straight lining												(17)	(242)	(240)
Amortization of acquired above and below market value leases												2	25	30
Investment income												173	101	122
General and administrative expenses												1,624	1,543	1,567
Depreciation												6,186	6,070	5,996
Deferred project cost write-off, net of income relating to early lease termination												776
Interest expense including amortization of deferred financing costs, and in 2010 a prepayment penalty of $2.1 million												(11,704)	(11,452)	(13,608)
Income from continuing operations												4,215	6,430	3,908
Income from discontinued operations												253	283	223
Gain on sale of discontinued operations (net of tax of $1,965)												7,528
Net income												11,996	6,713	4,131
Net (income) loss attributable to noncontrolling interests in subsidiaries												(645)	(1,335)	280
Net income attributable to common equity												$ 11,351	$ 5,378	$ 4,411

[1] (b) Includes deferred project cost write-off of $1,490 ($0.21 per share), and $2,236 ($0.32 per share) in the quarters ended April 30, and July 31, respectively.

[2] (c) Includes gain on sale of discontinued operation, net of tax, of $7,528 ($1.08 per share)