XML 173 R130.htm IDEA: XBRL DOCUMENT
v3.25.3

Insurance - Summary of Yield Curve Used to Discount Cash Flows that do not Vary Based on Underlying Items (Detail) | Oct. 31, 2025 | Oct. 31, 2024
--- | --- | ---
1 year [member] |  |
Disclosure of yield curve used to discount cash flows that do not vary based on returns on underlying items [line items] |  |
Yield used to discount cash flows that do not vary based on returns on underlying items | 3.24% | 4.16%
3 years [member] |  |
Disclosure of yield curve used to discount cash flows that do not vary based on returns on underlying items [line items] |  |
Yield used to discount cash flows that do not vary based on returns on underlying items | 3.54% | 4.17%
5 years [member] |  |
Disclosure of yield curve used to discount cash flows that do not vary based on returns on underlying items [line items] |  |
Yield used to discount cash flows that do not vary based on returns on underlying items | 3.89% | 4.35%
10 years [member] |  |
Disclosure of yield curve used to discount cash flows that do not vary based on returns on underlying items [line items] |  |
Yield used to discount cash flows that do not vary based on returns on underlying items | 4.67% | 4.82%
20 years [member] |  |
Disclosure of yield curve used to discount cash flows that do not vary based on returns on underlying items [line items] |  |
Yield used to discount cash flows that do not vary based on returns on underlying items | 5.25% | 5.15%
30 years [member] |  |
Disclosure of yield curve used to discount cash flows that do not vary based on returns on underlying items [line items] |  |
Yield used to discount cash flows that do not vary based on returns on underlying items | 4.99% | 4.98%
Ultimate [member] |  |
Disclosure of yield curve used to discount cash flows that do not vary based on returns on underlying items [line items] |  |
Yield used to discount cash flows that do not vary based on returns on underlying items | 5.00% | 5.00%

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_DisclosureOfYieldCurveUsedToDiscountCashFlowsThatDoNotVaryBasedOnReturnsOnUnderlyingItemsLineItems
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The yield used to discount cash flows that do not vary based on the returns on underlying items, applying paragraph 36 of IFRS 17. Underlying items are items that determine some of the amounts payable to a policyholder. Underlying items can comprise any items; for example a reference portfolio of assets, the net assets of the entity, or a specified subset of the net assets of the entity. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 17 -IssueDate 2024-01-01 -Paragraph 120 -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=17&code=ifrs-tx-2024-en-r&anchor=para_120&doctype=Standard -URIDate 2024-03-27 + Details
Name: | ifrs-full_YieldUsedToDiscountCashFlowsThatDoNotVaryBasedOnReturnsOnUnderlyingItems
Namespace Prefix: | ifrs-full_
Data Type: | dtr-2022:percentItemType
Balance Type: | na
Period Type: | instant

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_LaterThanTwoYearsAndNotLaterThanThreeYearsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

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

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

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

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