v3.25.1
Significant accounting policies - Additional Information (Detail) - shares
shares in Thousands
3 Months Ended 6 Months Ended
Apr. 30, 2025
Apr. 30, 2024
Apr. 30, 2025
Apr. 30, 2024
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) 336 74 264 74