XML 111 R68.htm IDEA: XBRL DOCUMENT
v3.25.3

IFRS 7 Disclosure - Market Risk - Structural Balance Sheet Interest Rate Sensitivity (Detail) - CAD ($) $ in Millions | Oct. 31, 2025 | Oct. 31, 2024
--- | --- | ---
Hundred basis point increase [member] |  |
Market Risk [Line Items] |  |
Pre tax economic value sensitivity | $ (1,736) | $ (1,483)
Pre tax earnings sensitivity over the next twelve month | 357 | 367
Hundred basis point increase [member] | Canada [member] |  |
Market Risk [Line Items] |  |
Pre tax economic value sensitivity | (986) |
Pre tax earnings sensitivity over the next twelve month | 104 |
Hundred basis point increase [member] | United States [member] |  |
Market Risk [Line Items] |  |
Pre tax economic value sensitivity | (750) |
Pre tax earnings sensitivity over the next twelve month | 252 |
Hundred basis point decrease [member] |  |
Market Risk [Line Items] |  |
Pre tax economic value sensitivity | 1,063 | 660
Pre tax earnings sensitivity over the next twelve month | (322) | $ (210)
Hundred basis point decrease [member] | Canada [member] |  |
Market Risk [Line Items] |  |
Pre tax economic value sensitivity | 983 |
Pre tax earnings sensitivity over the next twelve month | (26) |
Hundred basis point decrease [member] | United States [member] |  |
Market Risk [Line Items] |  |
Pre tax economic value sensitivity | 80 |
Pre tax earnings sensitivity over the next twelve month | $ (296) |

X
- Definition Market Risk [Line Items] + References No definition available. + Details
Name: | bmo_MarketRiskLineItems
Namespace Prefix: | bmo_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Pre- tax earnings sensitivity over the next twelve month. + References No definition available. + Details
Name: | bmo_PreTaxEarningsSensitivityOverTheNextTwelveMonth
Namespace Prefix: | bmo_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Pre- tax economic value sensitivity. + References No definition available. + Details
Name: | bmo_PreTaxEconomicValueSensitivity
Namespace Prefix: | bmo_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | ifrs-full_InternalCreditGradesAxis=bmo_HundredBasisPointIncreaseMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_GeographicalAreasAxis=country_CA
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_GeographicalAreasAxis=country_US
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_InternalCreditGradesAxis=bmo_HundredBasisPointDecreaseMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |