v3.19.2
share-based compensation - Employee share purchase plan (Details) - Employee share purchase plan - CAD ($)
$ in Millions
3 Months Ended 6 Months Ended
Jun. 30, 2019
Jun. 30, 2018
Jun. 30, 2019
Jun. 30, 2018
share-based compensation        
Dividend reinvestment in Common Shares $ 8 $ 9 $ 17 $ 17
Purchase plan discount     0.00% 0.00%