XML 168 R125.htm IDEA: XBRL DOCUMENT
v3.25.3

Other Liabilities - Additional Information (Detail) - CAD ($) $ in Millions | 12 Months Ended
--- | ---
Oct. 31, 2025 | Oct. 31, 2024
Text Block [Line Items] |  |
Interest expense on lease liabilities | $ 110 | $ 110
Cash outflow for leases | 426 | 455
Variable lease payments not included in the measurement of lease liabilities | 276 | $ 258
Year 2026 [member] |  |
Text Block [Line Items] |  |
Gross lease liabilities | 468 |
Year 2027 [member] |  |
Text Block [Line Items] |  |
Gross lease liabilities | 465 |
Year 2028 [member] |  |
Text Block [Line Items] |  |
Gross lease liabilities | 436 |
Year 2029 [member] |  |
Text Block [Line Items] |  |
Gross lease liabilities | 414 |
Year 2030 [member] |  |
Text Block [Line Items] |  |
Gross lease liabilities | 390 |
Year 2031 and Thereafter [member] |  |
Text Block [Line Items] |  |
Gross lease liabilities | $ 1,756 |

X
- Definition Text black [Line Item]. + References No definition available. + Details
Name: | bmo_TextBlockLineItems
Namespace Prefix: | bmo_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The cash outflow for leases. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 16 -IssueDate 2024-01-01 -Paragraph 53 -Subparagraph g -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=16&code=ifrs-tx-2024-en-r&anchor=para_53_g&doctype=Standard -URIDate 2024-03-27 + Details
Name: | ifrs-full_CashOutflowForLeases
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The amount of the expense relating to variable lease payments not included in the measurement of lease liabilities. Variable lease payments are the portion of payments made by a lessee to a lessor for the right to use an underlying asset during the lease term that varies because of changes in facts or circumstances occurring after the commencement date, other than the passage of time. [Refer: Lease liabilities] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 16 -IssueDate 2024-01-01 -Paragraph 53 -Subparagraph e -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=16&code=ifrs-tx-2024-en-r&anchor=para_53_e&doctype=Standard -URIDate 2024-03-27 + Details
Name: | ifrs-full_ExpenseRelatingToVariableLeasePaymentsNotIncludedInMeasurementOfLeaseLiabilities
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The amount of contractual undiscounted cash flows in relation to lease liabilities before deducting finance charges. [Refer: Lease liabilities] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 16 -IssueDate 2024-01-01 -Paragraph 58 -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=16&code=ifrs-tx-2024-en-r&anchor=para_58&doctype=Standard -URIDate 2024-03-27 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Name IFRS -Number 7 -IssueDate 2024-01-01 -Paragraph B11D -Subparagraph a -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2024-en-r&anchor=para_B11D_a&doctype=Appendix&subtype=B -URIDate 2024-03-27 + Details
Name: | ifrs-full_GrossLeaseLiabilities
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The amount of interest expense on lease liabilities. [Refer: Lease liabilities] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 16 -IssueDate 2024-01-01 -Paragraph 53 -Subparagraph b -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=16&code=ifrs-tx-2024-en-r&anchor=para_53_b&doctype=Standard -URIDate 2024-03-27 + Details
Name: | ifrs-full_InterestExpenseOnLeaseLiabilities
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

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_LaterThanOneYearAndNotLaterThanTwoYearsMember
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_LaterThanThreeYearsAndNotLaterThanFourYearsMember
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_LaterThanFiveYearsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |