Deposits and Subordinated Debt - Summary of Maturity Schedule for Deposits Greater than One Hundred Thousand Dollars Booked in Canada (Details) - CAD ($) $ in Millions	Apr. 30, 2026	Oct. 31, 2025
Disclosure of deposits payable to customers on a fixed date [line items]
Deposits	$ 966,901	$ 976,202
Canada
Disclosure of deposits payable to customers on a fixed date [line items]
Deposits	616,888	620,858
Canada \| Deposits More Than One Hundred Thousand Dollar
Disclosure of deposits payable to customers on a fixed date [line items]
Deposits	255,381	259,670
Canada \| Less than 3 months \| Deposits More Than One Hundred Thousand Dollar
Disclosure of deposits payable to customers on a fixed date [line items]
Deposits	48,873	51,591
Canada \| 3 to 6 months \| Deposits More Than One Hundred Thousand Dollar
Disclosure of deposits payable to customers on a fixed date [line items]
Deposits	33,260	32,105
Canada \| 6 to 12 months \| Deposits More Than One Hundred Thousand Dollar
Disclosure of deposits payable to customers on a fixed date [line items]
Deposits	53,017	56,129
Canada \| Over 12 months \| Deposits More Than One Hundred Thousand Dollar
Disclosure of deposits payable to customers on a fixed date [line items]
Deposits	$ 120,231	$ 119,845