XML 68 R54.htm IDEA: XBRL DOCUMENT v3.21.1
Stock-Based Compensation - Narrative (Details) - CAD ($)
$ / shares in Units, $ in Millions
3 Months Ended 12 Months Ended
Mar. 31, 2021
Mar. 31, 2020
Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Stock-based compensation expense $ 24 $ 11  
Stock Options      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Number of options issued 266,698    
Weighted-average grant price $ 437.94    
Expiration period 7 years    
Stock options grant date fair value $ 25    
Stock Options | Minimum      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Vesting period 12 months    
Stock Options | Maximum      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Vesting period 48 months    
Performance Share Units (PSUs)      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Units issued 84,672   125,280
Grant date fair value $ 36    
PSU payout percentage     200.00%
Number of trading days     30 days
Units paid in period 114,014    
Cash payout $ 98    
Performance Share Units (PSUs) | Retention Grant      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Units issued     36,975
Performance Deferred Share Units (PDSUs)      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Units issued 2,539    
Grant date fair value $ 1    
Number of additional PDSUs that can be granted as a percentage of original units granted 25.00%    
PSUs and PDSUs      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Vesting period 3 years    
Deferred Share Units (DSUs)      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Vesting period 36 months    
Units issued 9,170    
Grant date fair value $ 4