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IFRS 7 Disclosure - Credit and Counterparty Risk - Schedule of Total Credit Risk Exposures (Detail) - CAD ($) $ in Millions | Oct. 31, 2025 | Oct. 31, 2024
--- | --- | ---
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | $ 1,189,564 | $ 1,152,424
Individual sector [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 360,814 | 353,309
Financial institutions [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 152,980 | 178,414
Government sector [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 275,475 | 240,688
Manufacturing sector [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 53,288 | 51,861
Real estate sector [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 85,051 | 76,928
Retail trade sector [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 34,741 | 35,654
Service industries sector [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 77,954 | 72,445
Wholesale trade sector [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 31,188 | 30,018
Oil and gas sector [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 7,730 | 7,423
Utilities sector [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 25,771 | 25,615
Other sector [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 84,572 | 80,069
Drawn [Member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 917,167 | 898,000
Drawn [Member] | Individual sector [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 293,947 | 287,741
Drawn [Member] | Financial institutions [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 79,224 | 105,378
Drawn [Member] | Government sector [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 259,618 | 230,353
Drawn [Member] | Manufacturing sector [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 34,540 | 33,561
Drawn [Member] | Real estate sector [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 72,516 | 66,650
Drawn [Member] | Retail trade sector [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 29,470 | 30,595
Drawn [Member] | Service industries sector [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 59,153 | 54,433
Drawn [Member] | Wholesale trade sector [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 22,848 | 21,868
Drawn [Member] | Oil and gas sector [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 3,479 | 3,180
Drawn [Member] | Utilities sector [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 7,141 | 10,068
Drawn [Member] | Other sector [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 55,231 | 54,173
Undrawn commitments [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 181,819 | 170,128
Undrawn commitments [member] | Individual sector [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 66,867 | 65,568
Undrawn commitments [member] | Financial institutions [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 22,460 | 20,484
Undrawn commitments [member] | Government sector [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 3,137 | 3,024
Undrawn commitments [member] | Manufacturing sector [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 15,840 | 15,555
Undrawn commitments [member] | Real estate sector [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 10,750 | 8,632
Undrawn commitments [member] | Retail trade sector [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 4,258 | 4,262
Undrawn commitments [member] | Service industries sector [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 14,793 | 13,830
Undrawn commitments [member] | Wholesale trade sector [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 7,328 | 7,212
Undrawn commitments [member] | Oil and gas sector [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 3,064 | 3,010
Undrawn commitments [member] | Utilities sector [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 11,840 | 9,304
Undrawn commitments [member] | Other sector [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 21,482 | 19,247
Other off balance sheet items [Member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 24,348 | 25,409
Other off balance sheet items [Member] | Financial institutions [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 5,750 | 7,447
Other off balance sheet items [Member] | Government sector [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 1,663 | 1,760
Other off balance sheet items [Member] | Manufacturing sector [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 1,726 | 1,696
Other off balance sheet items [Member] | Real estate sector [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 1,265 | 1,234
Other off balance sheet items [Member] | Retail trade sector [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 855 | 645
Other off balance sheet items [Member] | Service industries sector [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 2,674 | 3,192
Other off balance sheet items [Member] | Wholesale trade sector [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 706 | 670
Other off balance sheet items [Member] | Oil and gas sector [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 510 | 623
Other off balance sheet items [Member] | Utilities sector [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 4,446 | 3,799
Other off balance sheet items [Member] | Other sector [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 4,753 | 4,343
Over the counter derivatives [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 45,048 | 40,105
Over the counter derivatives [member] | Financial institutions [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 26,790 | 27,393
Over the counter derivatives [member] | Government sector [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 8,631 | 4,481
Over the counter derivatives [member] | Manufacturing sector [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 1,182 | 1,049
Over the counter derivatives [member] | Real estate sector [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 520 | 412
Over the counter derivatives [member] | Retail trade sector [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 158 | 152
Over the counter derivatives [member] | Service industries sector [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 1,334 | 990
Over the counter derivatives [member] | Wholesale trade sector [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 306 | 268
Over the counter derivatives [member] | Oil and gas sector [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 677 | 610
Over the counter derivatives [member] | Utilities sector [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 2,344 | 2,444
Over the counter derivatives [member] | Other sector [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 3,106 | 2,306
Repo style transactions [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 21,182 | 18,782
Repo style transactions [member] | Individual sector [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 0 |
Repo style transactions [member] | Financial institutions [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | 18,756 | 17,712
Repo style transactions [member] | Government sector [member] |  |
Disclosure of credit risk exposure [line items] |  |
Total exposure at default | $ 2,426 | $ 1,070

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