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Employee Compensation - Share-Based Compensation - Summary of Further Information about our Stock Option Plan (Detail) - CAD ($) $ / shares in Units, $ in Millions | 12 Months Ended
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Oct. 31, 2025 | Oct. 31, 2024
Disclosure of number and weighted average exercise price of share options [abstract] |  |
Unrecognized compensation cost for non-vested stock option awards | $ 10 | $ 12
Cash proceeds from stock options exercised | $ 146 | $ 67
Weighted-average share price for stock options exercised (in dollars) | $ 152.59 | $ 120.4

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- Definition The disclosure of number and weighted average exercise price of share options. + References No definition available. + Details
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- Definition The cash inflow from the exercise of options. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 7 -IssueDate 2024-01-01 -Paragraph 17 -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=7&code=ifrs-tx-2024-en-r&anchor=para_17&doctype=Standard -URIDate 2024-03-27 + Details
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