Organization and significant accounting policies (Narrative) (Details) (USD $)	12 Months Ended
Oct. 31, 2014	Oct. 31, 2013	Oct. 31, 2012
Organization and significant accounting policies [Abstract]
Advertising costs	$ 133,000us-gaap_AdvertisingExpense	$ 93,000us-gaap_AdvertisingExpense	$ 127,000us-gaap_AdvertisingExpense
Amortization of mortgage costs and leasing commissions	$ 359,000us-gaap_AmortizationOfFinancingCosts	$ 370,000us-gaap_AmortizationOfFinancingCosts	$ 368,000us-gaap_AmortizationOfFinancingCosts

Amount of noncash expense included in interest expense to issue debt and obtain financing associated with the related debt instruments. Alternate captions include noncash interest expense.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.8)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 8

-Article 5

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 8

-Article 9

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Balance Type:	debit
Period Type:	duration