v3.24.3
Equity - Summary of Common and Preferred Shares and Other Equity Instruments Outstanding (Parenthetical) (Detail)
$ / shares in Units, $ / shares in Units, $ in Millions, $ in Millions
 12 Months Ended
Aug. 24, 2024
$ / shares
shares
Jul. 24, 2024
CAD ($)
$ / shares
shares
May 24, 2024
$ / shares
shares
Jan. 25, 2024
CAD ($)
shares
Nov. 07, 2023
$ / shares
shares
Oct. 31, 2024
CAD ($)
$ / shares
shares
Oct. 31, 2024
CAD ($)
$ / shares
$ / shares
shares
Oct. 31, 2023
CAD ($)
shares
Oct. 31, 2024
USD ($)
$ / shares
shares
Jun. 10, 2024
CAD ($)
Disclosure of classes of share capital [line items]                    
Proceeds from issue of preference shares | $           $ 2,702        
Equity | $           127,192 $ 127,192 $ 115,147    
Common shares [member]                    
Disclosure of classes of share capital [line items]                    
Fair value adjustments to stock options | $           $ 10   $ 6    
Average cost of shares purchased for cancellation           $ 157.74        
Average book value of shares purchased for cancellation           $ 14.83        
Book value of common shares purchased | $           $ 13 13      
Fair value of common shares purchased | $           $ 140 $ 140      
Common shares [member] | Top of range [member]                    
Disclosure of classes of share capital [line items]                    
Purchase Of Common Share | $                   $ 30
Series C2 non-cumulative fixed rate/floating first preferred shares [member]                    
Disclosure of classes of share capital [line items]                    
Preferred shares issued price per share | (per share)           $ 1,000 $ 1,000      
Preferred shares issued price per depositary share             $ 25      
Number of shares issued | shares               15,000    
Equity | $               $ 23    
Series C2 non-cumulative fixed rate/floating first preferred shares [member] | Major ordinary share transactions [member]                    
Disclosure of classes of share capital [line items]                    
Number of shares redeemed | shares         615,000          
Redemption price per share         $ 1,000          
Redemption price per depositary share         $ 25          
Series BQ on non-cumulative reset five year rate first preference shares [member] | Consolidated limited recourse trust [member]                    
Disclosure of classes of share capital [line items]                    
Equity | $           $ 1,750 $ 1,750      
Shares issued price per share           $ 1,000 $ 1,000      
Series BR non-cumulative reset five year rate first preference shares [member] | Consolidated limited recourse trust [member]                    
Disclosure of classes of share capital [line items]                    
Equity | $           $ 1,250 $ 1,250      
Shares issued price per share           $ 1,000 $ 1,000      
Series BS non-cumulative reset five year rate first preference shares [member] | Consolidated limited recourse trust [member]                    
Disclosure of classes of share capital [line items]                    
Equity | $           $ 1,000 $ 1,000      
Shares issued price per share           $ 1,000 $ 1,000      
Series BT non-cumulative 5-year rate reset first preferred shares [member]                    
Disclosure of classes of share capital [line items]                    
Preferred shares issued price per share           25        
Series AZ non-cumulative 5-year rate reset first preferred share [member]                    
Disclosure of classes of share capital [line items]                    
Number of shares redeemed | shares     20,000,000              
Redemption price per share     $ 25              
Series BB non-cumulative 5-year rate reset first preferred share [member]                    
Disclosure of classes of share capital [line items]                    
Number of shares redeemed | shares 20,000,000                  
Redemption price per share $ 25                  
Series BU non-cumulative 5-year rate reset first preference shares [member]                    
Disclosure of classes of share capital [line items]                    
Redemption price per share           $ 1,000 $ 1,000      
Number of shares issued | shares       750,000   750,000 750,000   750,000  
Par value per share           $ 1,000 $ 1,000      
Proceeds from issue of preference shares | $       $ 750            
Equity | $           $ 750 $ 750      
Series BW non-cumulative 5-year rate reset first preference shares [member]                    
Disclosure of classes of share capital [line items]                    
Redemption price per share           $ 1,000 $ 1,000      
Number of shares issued | shares   600,000       600,000 600,000   600,000  
Par value per share   $ 1,000                
Proceeds from issue of preference shares | $   $ 600                
Equity | $           $ 600 $ 600      
Series 4 limited recourse capital notes [member]                    
Disclosure of classes of share capital [line items]                    
Preferred shares issued price per share             $ 1,000      
Redemption price per share                 $ 1,000  
Shares issued price per share           $ 1,000 $ 1,000      
Series BV non-cumulative 5-year rate reset first preference shares [member] | Consolidated limited recourse trust [member]                    
Disclosure of classes of share capital [line items]                    
Equity | $                 $ 1,000  
First Preferred Shares Series BV [member] | Consolidated limited recourse trust [member]                    
Disclosure of classes of share capital [line items]                    
Equity | $                 $ 1,000