XML 136 R111.htm IDEA: XBRL DOCUMENT v3.20.4
STOCK OPTION AND STOCK UNIT PLANS - WEIGHTED AVERAGE ASSUMPTIONS (Details)
$ / shares in Units, $ in Millions
12 Months Ended
Dec. 31, 2020
CAD ($)
$ / shares
Dec. 31, 2019
CAD ($)
$ / shares
Dec. 31, 2018
CAD ($)
$ / shares
Dec. 31, 2020
$ / shares
Dec. 31, 2019
$ / shares
Dec. 31, 2018
$ / shares
Weighted average assumptions used to determine the fair value of options            
Compensation expense | $ $ 145 $ 117 $ 106      
INCENTIVE STOCK OPTIONS            
Weighted average assumptions used to determine the fair value of options            
Fair value per option (in dollars per share) | $ / shares $ 4.01 $ 4.37 $ 3.86      
Expected option term (in years) 6 years 5 years 5 years      
Expected volatility (as a percent) 18.30% 19.90% 21.90%      
Expected dividend yield (as a percent) 5.90% 6.10% 6.40%      
Risk-free interest rate (as a percent) 1.30% 2.00% 2.20%      
Expected option term - historical exercise practice 6 years          
Compensation expense | $ $ 24 $ 32 $ 28      
Unrecognized compensation cost related to non-vested share-based compensation arrangements granted | $ $ 13          
Weighted average period over which compensation cost is expected to be recognized 2 years          
INCENTIVE STOCK OPTIONS | Canadian employees            
Weighted average assumptions used to determine the fair value of options            
Fair value per option (in dollars per share) | $ / shares $ 3.75 $ 4.04 $ 3.75      
INCENTIVE STOCK OPTIONS | United States employees            
Weighted average assumptions used to determine the fair value of options            
Fair value per option (in dollars per share) | $ / shares       $ 3.62 $ 4.09 $ 3.30
INCENTIVE STOCK OPTIONS | Retirement-eligible employees            
Weighted average assumptions used to determine the fair value of options            
Expected option term (in years) 5 years