Significant accounting policies - Additional Information (Detail) - shares shares in Thousands	3 Months Ended	6 Months Ended
Apr. 30, 2023	Apr. 30, 2022	Apr. 30, 2023	Apr. 30, 2022
Significant Accounting Policies [Line Items]
Less than 50% Ownership Percentage, Accounted for under the Equity Method of Investment	50.00%		50.00%
Stock Options
Significant Accounting Policies [Line Items]
Options for common shares excluded from computation of diluted earning per share (in shares)	140	77	142	80

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=124432515&loc=d3e3550-109257

Name:	us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration