v3.22.2.2
Summary of significant accounting policies, estimates and judgments - Additional Information (Detail) - CAD ($)
$ in Millions
 12 Months Ended
Oct. 31, 2022
Oct. 31, 2021
Significant Accounting Policies, Estimates and Judgments [Line Items]    
Non-derivative financial assets $ 75,987 $ 77,551
Non-derivative financial liabilities 20,040 16,217
Derivative notional amount 7,776,875 6,415,878
Authorized and committed undrawn commitments $ 86,184 138,081
Non Usd Libor [Member]    
Significant Accounting Policies, Estimates and Judgments [Line Items]    
Non-derivative financial assets   3,600
Non-derivative financial liabilities   3,400
Derivative notional amount   2,975,400
Authorized and committed undrawn commitments   $ 3,000
Computer software [member]    
Significant Accounting Policies, Estimates and Judgments [Line Items]    
Estimated useful lives of intangible assets 3 to 10 years  
Customer relationships [member]    
Significant Accounting Policies, Estimates and Judgments [Line Items]    
Estimated useful lives of intangible assets 10 to 20 years  
Buildings [member]    
Significant Accounting Policies, Estimates and Judgments [Line Items]    
Useful life of premises and equipment 25 to 50 years  
Computer equipment [member]    
Significant Accounting Policies, Estimates and Judgments [Line Items]    
Useful life of premises and equipment 3 to 10 years  
Furniture Fixtures and Other Equipment [member]    
Significant Accounting Policies, Estimates and Judgments [Line Items]    
Useful life of premises and equipment 5 to 10 years