XML 90 R80.htm IDEA: XBRL DOCUMENT
v3.25.2

Earnings per Share - Summary of Earnings Per Share (Parenthetical) (Detail) - $ / shares | 3 Months Ended | 9 Months Ended
--- | --- | ---
Jul. 31, 2025 | Apr. 30, 2025 | Jul. 31, 2024 | Jul. 31, 2025 | Jul. 31, 2024
Earnings per share [abstract] |  |  |  |  |
Outstanding options excluded from calculation of diluted earnings per share | 0 | 2,422,512 | 2,553,244 | 2,150,302 | 2,553,244
Weighted average Exercise price of average outstanding share options excluded from the calculation of diluted earnings per share | $ 0 | $ 94.35 | $ 70.05 | $ 94.35 | $ 70.05

X
- Definition Disclosure of instruments with potential future dilutive effect not included in calculation of diluted earnings per share + References No definition available. + Details
Name: | cm_DisclosureOfInstrumentsWithPotentialFutureDilutiveEffectNotIncludedInCalculationOfDilutedEarningsPerShare
Namespace Prefix: | cm_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Weighted average exercise price of average outstanding share options excluded from calculation of diluted earnings per share. + References No definition available. + Details
Name: | cm_WeightedAverageExercisePriceOfAverageOutstandingShareOptionsExcludedFromCalculationOfDilutedEarningsPerShare
Namespace Prefix: | cm_
Data Type: | dtr-types:perShareItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | ifrs-full_EarningsPerShareAbstract
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration