v3.26.1
Fair Value of Financial Instruments - Summary of Changes in Level 3 Instruments Carried at Fair Value (Detail) - Level 3 [member] - CAD ($)
$ in Millions
 3 Months Ended 9 Months Ended
Jul. 31, 2026
Jul. 31, 2025
Jul. 31, 2026
Jul. 31, 2025
Disclosure of significant unobservable inputs used in fair value measurement of equity [line items]        
Fair value, beginning balance $ 2,088   $ 2,211  
Gains/(losses) recorded in income 26   100  
Gains/(losses) recorded in OCI     24  
Purchases/ Issuances 161   474  
Sales/ Settlements (131)   (632)  
Transfers into Level 3     43  
Transfers out of Level 3 3   (73)  
Fair value, ending balance 2,147   2,147  
Change in unrealized gains/(losses)recorded in income for instruments still held 26   115  
Derivative financial instruments [member]        
Disclosure of significant unobservable inputs used in fair value measurement of equity [line items]        
Fair value, beginning balance   $ (8)   $ 10
Gains/(losses) recorded in income [1]   (3)   (15)
Purchases/ Issuances   (6)   (2)
Sales/ Settlements   12   20
Transfers into Level 3       (15)
Transfers out of Level 3   3    
Fair value, ending balance   (2)   (2)
Derivative financial liabilities [member]        
Disclosure of significant unobservable inputs used in fair value measurement of equity [line items]        
Fair value, beginning balance 6   120  
Gains/(losses) recorded in income [1] 7   4  
Purchases/ Issuances 14   11  
Sales/ Settlements (6)   (76)  
Transfers into Level 3     31  
Transfers out of Level 3 9   (60)  
Fair value, ending balance 30   30  
Change in unrealized gains/(losses)recorded in income for instruments still held [2] 7   18  
Obligations related to securities sold short [member]        
Disclosure of significant unobservable inputs used in fair value measurement of equity [line items]        
Fair value, beginning balance       (2)
Transfers into Level 3 (1)   (1)  
Transfers out of Level 3       2
Fair value, ending balance (1)   (1)  
Trading assets [member]        
Disclosure of significant unobservable inputs used in fair value measurement of equity [line items]        
Fair value, beginning balance 163 9 13 25
Gains/(losses) recorded in income [1] 3   (15) 1
Gains/(losses) recorded in OCI     (3)  
Purchases/ Issuances 5 2 174 6
Sales/ Settlements (8) (3) (11) (18)
Transfers into Level 3 1 179 13 192
Transfers out of Level 3 (6) (3) (13) (22)
Fair value, ending balance 158 184 158 184
Change in unrealized gains/(losses)recorded in income for instruments still held [2] 3   (14)  
Trading assets [member] | Equity securities [member]        
Disclosure of significant unobservable inputs used in fair value measurement of equity [line items]        
Fair value, beginning balance 17   12  
Gains/(losses) recorded in income [1] (1)   (2)  
Purchases/ Issuances 5   9  
Sales/ Settlements (8)   (11)  
Transfers into Level 3 1   12  
Transfers out of Level 3 (6)   (12)  
Fair value, ending balance 8   8  
Change in unrealized gains/(losses)recorded in income for instruments still held [2] (1)   (1)  
Trading assets [member] | Trading loans [member]        
Disclosure of significant unobservable inputs used in fair value measurement of equity [line items]        
Fair value, beginning balance 146   1  
Gains/(losses) recorded in income [1] 4   (13)  
Gains/(losses) recorded in OCI     (3)  
Purchases/ Issuances     165  
Transfers into Level 3     1  
Transfers out of Level 3     (1)  
Fair value, ending balance 150   150  
Change in unrealized gains/(losses)recorded in income for instruments still held [2] 4   (13)  
Investment securities [member]        
Disclosure of significant unobservable inputs used in fair value measurement of equity [line items]        
Fair value, beginning balance 1,919 1,988 2,078 1,901
Gains/(losses) recorded in income [1] 16 43 111 107
Gains/(losses) recorded in OCI   3 27 62
Purchases/ Issuances 142 49 289 149
Sales/ Settlements (117) (18) (545) (137)
Transfers into Level 3   12   12
Transfers out of Level 3       (17)
Fair value, ending balance 1,960 $ 2,077 1,960 $ 2,077
Change in unrealized gains/(losses)recorded in income for instruments still held [2] 16   111  
Investment securities [member] | Equity securities [member]        
Disclosure of significant unobservable inputs used in fair value measurement of equity [line items]        
Fair value, beginning balance 1,910   2,046  
Gains/(losses) recorded in income [1] 16   111  
Gains/(losses) recorded in OCI 1   30  
Purchases/ Issuances 121   267  
Sales/ Settlements (117)   (523)  
Fair value, ending balance 1,931   1,931  
Change in unrealized gains/(losses)recorded in income for instruments still held [2] 16   111  
Investment securities [member] | Corporate and Other Debt [member]        
Disclosure of significant unobservable inputs used in fair value measurement of equity [line items]        
Fair value, beginning balance 9   32  
Gains/(losses) recorded in OCI (1)   (3)  
Purchases/ Issuances 21   22  
Sales/ Settlements     (22)  
Fair value, ending balance 29   29  
Derivative financial assets [member] | Interest rate contracts (Assets) [member]        
Disclosure of significant unobservable inputs used in fair value measurement of equity [line items]        
Fair value, beginning balance     3  
Gains/(losses) recorded in income [1]     (1)  
Sales/ Settlements     (2)  
Change in unrealized gains/(losses)recorded in income for instruments still held [2],[3]     (1)  
Derivative financial assets [member] | Equity contracts (Assets) [member]        
Disclosure of significant unobservable inputs used in fair value measurement of equity [line items]        
Fair value, beginning balance 29   161  
Gains/(losses) recorded in income [1] 1   (9)  
Purchases/ Issuances 5   12  
Sales/ Settlements     (70)  
Transfers into Level 3     31  
Transfers out of Level 3 (10)   (100)  
Fair value, ending balance 25   25  
Change in unrealized gains/(losses)recorded in income for instruments still held [2],[4] 1   11  
Derivative financial assets [member] | Commodity Contracts (Assets) [member]        
Disclosure of significant unobservable inputs used in fair value measurement of equity [line items]        
Fair value, beginning balance 7   16  
Gains/(losses) recorded in income [1] 5   (4)  
Fair value, ending balance 12   12  
Change in unrealized gains/(losses)recorded in income for instruments still held [2] 5   (4)  
Derivative financial assets [member] | Credit Contracts [member]        
Disclosure of significant unobservable inputs used in fair value measurement of equity [line items]        
Fair value, beginning balance 9   4  
Gains/(losses) recorded in income [1]     2  
Purchases/ Issuances 21   24  
Sales/ Settlements (8)   (8)  
Fair value, ending balance 22   22  
Change in unrealized gains/(losses)recorded in income for instruments still held [2]     2  
Derivative financial assets [member] | Foreign exchange and gold contracts [member]        
Disclosure of significant unobservable inputs used in fair value measurement of equity [line items]        
Fair value, beginning balance 1   1  
Gains/(losses) recorded in income [1] 1   1  
Transfers into Level 3     1  
Transfers out of Level 3 (1)   (2)  
Fair value, ending balance 1   1  
Change in unrealized gains/(losses)recorded in income for instruments still held [2] 1   1  
Interest rate contracts (Assets) [member] | Derivative financial liabilities [member]        
Disclosure of significant unobservable inputs used in fair value measurement of equity [line items]        
Fair value, beginning balance (1)   (8)  
Gains/(losses) recorded in income [1]     4  
Purchases/ Issuances     (1)  
Sales/ Settlements     1  
Transfers into Level 3     (1)  
Transfers out of Level 3 1   5  
Change in unrealized gains/(losses)recorded in income for instruments still held [2],[3]     (2)  
Equity contracts (Assets) [member] | Derivative financial liabilities [member]        
Disclosure of significant unobservable inputs used in fair value measurement of equity [line items]        
Fair value, beginning balance (28)   (43)  
Gains/(losses) recorded in income [1]     9  
Purchases/ Issuances (10)   (22)  
Transfers out of Level 3 19   37  
Fair value, ending balance (19)   (19)  
Change in unrealized gains/(losses)recorded in income for instruments still held [2],[4]     9  
Credit Contracts [member] | Derivative financial liabilities [member]        
Disclosure of significant unobservable inputs used in fair value measurement of equity [line items]        
Fair value, beginning balance (2)   (2)  
Purchases/ Issuances (2)   (2)  
Sales/ Settlements 1   1  
Fair value, ending balance (3)   (3)  
Commodity Contracts (Assets) [member] | Derivative financial liabilities [member]        
Disclosure of significant unobservable inputs used in fair value measurement of equity [line items]        
Fair value, beginning balance (9)   (12)  
Gains/(losses) recorded in income [1]     2  
Sales/ Settlements 1   2  
Fair value, ending balance $ (8)   (8)  
Change in unrealized gains/(losses)recorded in income for instruments still held [2]     $ 2  
[1] Gains or losses for items in Level 3 may be offset with losses or gains on related hedges in Level 1 or Level 2.
[2] These amounts represent the gains and losses from fair value changes of Level 3 instruments still held at the end of the period that are recorded in the Consolidated Statement of Income.
[3] Certain unrealized gains and losses on interest rate derivative contracts are largely offset by mark-to-market changes on embedded derivatives on certain deposit liabilities in the Consolidated Statement of Income.
[4] Certain unrealized gains and losses on derivative assets and liabilities are largely offset by mark-to-market changes on other instruments included in trading revenues in the Consolidated Statement of Income, since these instruments act as an economic hedge to certain derivative assets and liabilities.