XML 179 R116.htm IDEA: XBRL DOCUMENT
v3.25.3

Loans - Summary of Base Case Forecasts for Select Forward Looking Information Variables Used to Estimate our Expected Credit Losses (Detail) - Average Value [member] - USD ($) | 12 Months Ended
--- | ---
Oct. 31, 2025 | Oct. 31, 2024
Base case [member] | Within 1 year [member] |  |
Disclosure of internal credit grades [line items] |  |
Canadian Real GDP year-over-year growth | 1.10% | 1.60%
United States Real GDP year-over-year growth | 2.00% | 2.00%
Canadian unemployment rate | 6.80% | 6.60%
United States unemployment rate | 4.40% | 4.50%
Canadian Housing Price Index growth | 0.80% | 2.60%
Canadian household debt service ratio | 14.60% | 14.80%
West Texas Intermediate Oil Price | $ 70 | $ 78
Base case [member] | Later than one year [member] |  |
Disclosure of internal credit grades [line items] |  |
Canadian Real GDP year-over-year growth | 2.00% | 2.30%
United States Real GDP year-over-year growth | 1.80% | 2.00%
Canadian unemployment rate | 6.10% | 5.90%
United States unemployment rate | 4.10% | 4.00%
Canadian Housing Price Index growth | 2.70% | 2.50%
Canadian household debt service ratio | 14.70% | 14.80%
West Texas Intermediate Oil Price | $ 67 | $ 74
Upside case [member] | Within 1 year [member] |  |
Disclosure of internal credit grades [line items] |  |
Canadian Real GDP year-over-year growth | 1.70% | 2.50%
United States Real GDP year-over-year growth | 2.80% | 3.00%
Canadian unemployment rate | 6.40% | 5.70%
United States unemployment rate | 3.90% | 3.70%
Canadian Housing Price Index growth | 3.90% | 7.10%
Canadian household debt service ratio | 14.30% | 14.40%
West Texas Intermediate Oil Price | $ 74 | $ 88
Upside case [member] | Later than one year [member] |  |
Disclosure of internal credit grades [line items] |  |
Canadian Real GDP year-over-year growth | 2.40% | 2.70%
United States Real GDP year-over-year growth | 2.80% | 2.90%
Canadian unemployment rate | 5.50% | 5.20%
United States unemployment rate | 3.50% | 3.30%
Canadian Housing Price Index growth | 4.70% | 4.00%
Canadian household debt service ratio | 14.40% | 14.70%
West Texas Intermediate Oil Price | $ 83 | $ 100
Downside case [member] | Within 1 year [member] |  |
Disclosure of internal credit grades [line items] |  |
Canadian Real GDP year-over-year growth | (0.40%) | 0.40%
United States Real GDP year-over-year growth | 0.70% | 0.70%
Canadian unemployment rate | 7.40% | 7.20%
United States unemployment rate | 5.00% | 5.10%
Canadian Housing Price Index growth | (3.70%) | (2.30%)
Canadian household debt service ratio | 15.20% | 15.30%
West Texas Intermediate Oil Price | $ 54 | $ 60
Downside case [member] | Later than one year [member] |  |
Disclosure of internal credit grades [line items] |  |
Canadian Real GDP year-over-year growth | 1.10% | 1.40%
United States Real GDP year-over-year growth | 1.00% | 0.90%
Canadian unemployment rate | 7.00% | 6.80%
United States unemployment rate | 4.60% | 4.70%
Canadian Housing Price Index growth | (0.50%) | 0.90%
Canadian household debt service ratio | 15.60% | 15.20%
West Texas Intermediate Oil Price | $ 58 | $ 61

X
- Definition Annual percentage change in Canadian real GDP. + References No definition available. + Details
Name: | cm_AnnualPercentageChangeInCanadianRealGDP
Namespace Prefix: | cm_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Annual percentage change in united states real gdp. + References No definition available. + Details
Name: | cm_AnnualPercentageChangeInUnitedStatesRealGdp
Namespace Prefix: | cm_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Canadian percentage of unemployment rate. + References No definition available. + Details
Name: | cm_CanadianPercentageOfUnemploymentRate
Namespace Prefix: | cm_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of Canadian household debt service ratio. + References No definition available. + Details
Name: | cm_PercentageOfCanadianHouseholdDebtServiceRatio
Namespace Prefix: | cm_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of Canadian housing price index growth rate. + References No definition available. + Details
Name: | cm_PercentageOfCanadianHousingPriceIndexGrowthRate
Namespace Prefix: | cm_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition United states percentage unemployment rate. + References No definition available. + Details
Name: | cm_UnitedStatesPercentageUnemploymentRate
Namespace Prefix: | cm_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition West Texas intermediate oil price + References No definition available. + Details
Name: | cm_WestTexasIntermediateOilPrice
Namespace Prefix: | cm_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | duration

X
- Definition Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table. + References No definition available. + Details
Name: | ifrs-full_DisclosureOfInternalCreditExposuresLineItems
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | ifrs-full_RangeAxis=cm_AverageValueMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_StatementScenarioAxis=cm_BaseCaseScenarioMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=ifrs-full_NotLaterThanOneYearMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=ifrs-full_LaterThanOneYearMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_StatementScenarioAxis=cm_UpsideCaseScenarioMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_StatementScenarioAxis=cm_DownSideCaseScenarioMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |