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Securities - Schedule of Unrealized Gains and Losses (Detail) - CAD ($) $ in Millions | Oct. 31, 2025 | Oct. 31, 2024
--- | --- | ---
Disclosure of financial assets [line items] |  |  |
FVOCI Securities |  | $ 113,209 | $ 93,702
Cost/Amortized cost [member] |  |  |
Disclosure of financial assets [line items] |  |  |
FVOCI Securities |  | 112,197 | 93,728
Gross Unrealized Gains [member] |  |  |
Disclosure of financial assets [line items] |  |  |
FVOCI Securities |  | 1,369 | 660
Gross Unrealized Losses [member] |  |  |
Disclosure of financial assets [line items] |  |  |
FVOCI Securities |  | (357) | (686)
Fair value [member] |  |  |
Disclosure of financial assets [line items] |  |  |
FVOCI Securities |  | 113,209 | 93,702
Canadian federal government [member] | Cost/Amortized cost [member] |  |  |
Disclosure of financial assets [line items] |  |  |
FVOCI Securities |  | 44,894 | 33,892
Canadian federal government [member] | Gross Unrealized Gains [member] |  |  |
Disclosure of financial assets [line items] |  |  |
FVOCI Securities |  | 443 | 303
Canadian federal government [member] | Gross Unrealized Losses [member] |  |  |
Disclosure of financial assets [line items] |  |  |
FVOCI Securities |  | (2) | (18)
Canadian federal government [member] | Fair value [member] |  |  |
Disclosure of financial assets [line items] |  |  |
FVOCI Securities |  | 45,335 | 34,177
Canadian Provincial And Municipal Governments [member] | Cost/Amortized cost [member] |  |  |
Disclosure of financial assets [line items] |  |  |
FVOCI Securities |  | 5,525 | 5,939
Canadian Provincial And Municipal Governments [member] | Gross Unrealized Gains [member] |  |  |
Disclosure of financial assets [line items] |  |  |
FVOCI Securities |  | 132 | 82
Canadian Provincial And Municipal Governments [member] | Gross Unrealized Losses [member] |  |  |
Disclosure of financial assets [line items] |  |  |
FVOCI Securities |  | (13) | (25)
Canadian Provincial And Municipal Governments [member] | Fair value [member] |  |  |
Disclosure of financial assets [line items] |  |  |
FVOCI Securities |  | 5,644 | 5,996
U.S. federal government [member] | Cost/Amortized cost [member] |  |  |
Disclosure of financial assets [line items] |  |  |
FVOCI Securities |  | 20,515 | 17,033
U.S. federal government [member] | Gross Unrealized Gains [member] |  |  |
Disclosure of financial assets [line items] |  |  |
FVOCI Securities |  | 327 | 100
U.S. federal government [member] | Gross Unrealized Losses [member] |  |  |
Disclosure of financial assets [line items] |  |  |
FVOCI Securities |  | (33) | (168)
U.S. federal government [member] | Fair value [member] |  |  |
Disclosure of financial assets [line items] |  |  |
FVOCI Securities |  | 20,809 | 16,965
U.S. states, municipalities and agencies [member] | Cost/Amortized cost [member] |  |  |
Disclosure of financial assets [line items] |  |  |
FVOCI Securities |  | 5,622 | 5,125
U.S. states, municipalities and agencies [member] | Gross Unrealized Gains [member] |  |  |
Disclosure of financial assets [line items] |  |  |
FVOCI Securities |  | 77 | 24
U.S. states, municipalities and agencies [member] | Gross Unrealized Losses [member] |  |  |
Disclosure of financial assets [line items] |  |  |
FVOCI Securities |  | (65) | (81)
U.S. states, municipalities and agencies [member] | Fair value [member] |  |  |
Disclosure of financial assets [line items] |  |  |
FVOCI Securities |  | 5,634 | 5,068
Other governments [member] | Cost/Amortized cost [member] |  |  |
Disclosure of financial assets [line items] |  |  |
FVOCI Securities |  | 4,039 | 5,643
Other governments [member] | Gross Unrealized Gains [member] |  |  |
Disclosure of financial assets [line items] |  |  |
FVOCI Securities |  | 35 | 20
Other governments [member] | Gross Unrealized Losses [member] |  |  |
Disclosure of financial assets [line items] |  |  |
FVOCI Securities |  | (9) | (7)
Other governments [member] | Fair value [member] |  |  |
Disclosure of financial assets [line items] |  |  |
FVOCI Securities |  | 4,065 | 5,656
NHA MBS, U.S. agency MBS and CMO [member] | Cost/Amortized cost [member] |  |  |
Disclosure of financial assets [line items] |  |  |
FVOCI Securities | [1] | 26,946 | 21,570
NHA MBS, U.S. agency MBS and CMO [member] | Gross Unrealized Gains [member] |  |  |
Disclosure of financial assets [line items] |  |  |
FVOCI Securities |  | 291 | 58
NHA MBS, U.S. agency MBS and CMO [member] | Gross Unrealized Losses [member] |  |  |
Disclosure of financial assets [line items] |  |  |
FVOCI Securities |  | (222) | (335)
NHA MBS, U.S. agency MBS and CMO [member] | Fair value [member] |  |  |
Disclosure of financial assets [line items] |  |  |
FVOCI Securities |  | 27,015 | 21,293
Corporate debt [member] | Cost/Amortized cost [member] |  |  |
Disclosure of financial assets [line items] |  |  |
FVOCI Securities |  | 4,491 | 4,391
Corporate debt [member] | Gross Unrealized Gains [member] |  |  |
Disclosure of financial assets [line items] |  |  |
FVOCI Securities |  | 37 | 31
Corporate debt [member] | Gross Unrealized Losses [member] |  |  |
Disclosure of financial assets [line items] |  |  |
FVOCI Securities |  | (13) | (52)
Corporate debt [member] | Fair value [member] |  |  |
Disclosure of financial assets [line items] |  |  |
FVOCI Securities |  | 4,515 | 4,370
Corporate equity [member] | Cost/Amortized cost [member] |  |  |
Disclosure of financial assets [line items] |  |  |
FVOCI Securities |  | 165 | 135
Corporate equity [member] | Gross Unrealized Gains [member] |  |  |
Disclosure of financial assets [line items] |  |  |
FVOCI Securities |  | 27 | 42
Corporate equity [member] | Fair value [member] |  |  |
Disclosure of financial assets [line items] |  |  |
FVOCI Securities |  | $ 192 | $ 177
[1] | These amounts are either supported by insured mortgages or issued by U.S. agencies and government-sponsored enterprises. NHA refers to the National Housing Act, MBS refers to mortgage-backed securities and CMO refers to collateralized mortgage obligations.

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