Selected quarterly financial data (Details) (USD $) In Thousands, except Per Share data, 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
Selected Quarterly Financial Data Details
Revenue	$ 10,476		$ 10,668		$ 13,510	[1]	$ 10,820	$ 11,031	$ 10,679	$ 10,726	$ 10,610	$ 45,474	$ 43,046	$ 43,115
Expenses	9,424		11,682	[2]	10,818	[2]	9,335	9,281	8,919	9,103	9,313	29,728	25,265	25,721
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	[3]	123		75		77	76	74	70	63	253	283	223
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
Basic earnings per share:
Continuing operations	$ 0.14		$ (0.05)		$ 0.27	[1],[2]	$ 0.16	$ 0.21	$ 0.21	$ 0.18	$ 0.13	$ 0.52	$ 0.73	$ 0.61
Discontinued operations	$ 1.08	[3]	$ 0.02		$ 0.01		$ 0.01	$ 0.01	$ 0.01	$ 0.01	$ 0.01	$ 1.12	$ 0.04	$ 0.03
Net income attributable to common equity	$ 1.22		$ (0.03)		$ 0.28		$ 0.17	$ 0.22	$ 0.22	$ 0.19	$ 0.14	$ 1.64	$ 0.77	$ 0.64
Dividends per share	$ 0.20		$ 0.30		$ 0.30		$ 0.30	$ 0.30	$ 0.30	$ 0.30	$ 0.30	$ 1.10	$ 1.20	$ 1.20

[1] (a) Includes income related to early lease termination of $2,950 ($0.42 per share)

[2] (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.

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