XML 234 R171.htm IDEA: XBRL DOCUMENT
v3.25.3

Post-Employment Benefits - Summary of Defined Benefit Plan Expense (Detail) - CAD ($) $ in Millions | 12 Months Ended
--- | ---
Oct. 31, 2025 | Oct. 31, 2024
Pension plan [member] |  |
Disclosure of defined benefit plans [line items] |  |
Current service cost | $ 227 | $ 190
Interest cost on defined benefit obligation | 386 | 396
Interest income on plan assets | (462) | (459)
Interest expense on effect of asset ceiling | 3 | 1
Plan administration costs | 7 | 8
Net defined benefit plan expense recognized in net income | 161 | 136
Other post employment benefit plans [member] |  |
Disclosure of defined benefit plans [line items] |  |
Current service cost | 5 | 5
Interest cost on defined benefit obligation | 20 | 24
Net defined benefit plan expense recognized in net income | $ 25 | $ 29

X
- Definition Interest expense, net defined benefit liability (asset). + References No definition available. + Details
Name: | cm_InterestExpenseNetDefinedBenefitLiabilityAsset
Namespace Prefix: | cm_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Interest expense on asset ceiling. + References No definition available. + Details
Name: | cm_InterestExpenseOnAssetCeiling
Namespace Prefix: | cm_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Interest income net defined benefit liability asset. + References No definition available. + Details
Name: | cm_InterestIncomeNetDefinedBenefitLiabilityAsset
Namespace Prefix: | cm_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Net defined benefit plan expense recognized in net income. + References No definition available. + Details
Name: | cm_NetDefinedBenefitPlanExpenseRecognizedInNetIncome
Namespace Prefix: | cm_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The increase (decrease) in the net defined benefit liability (asset) resulting from employee service in the current period. [Refer: Net defined benefit liability (asset)] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2024-01-01 -Paragraph 141 -Subparagraph a -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2024-en-r&anchor=para_141_a&doctype=Standard -URIDate 2024-03-27 + Details
Name: | ifrs-full_CurrentServiceCostNetDefinedBenefitLiabilityAsset
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
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_DisclosureOfDefinedBenefitPlansLineItems
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The decrease (increase) in the net defined benefit liability (asset) resulting from payments from the plan. [Refer: Net defined benefit liability (asset)] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2024-01-01 -Paragraph 141 -Subparagraph g -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2024-en-r&anchor=para_141_g&doctype=Standard -URIDate 2024-03-27 + Details
Name: | ifrs-full_PaymentsFromPlanNetDefinedBenefitLiabilityAsset
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | cm_DefinedBenefitPlansByNameAxis=cm_PensionPlanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | cm_DefinedBenefitPlansByNameAxis=cm_OtherPostEmploymentBenefitPlansMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |