XML 54 R72.htm IDEA: XBRL DOCUMENT v3.19.3.a.u2
Litigation and Other Contingencies - Additional Information (Detail) - CAD ($)
$ in Millions
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Litigation And Other Contingencies [Line Items]    
Total payment on unconditional purchase obligation $ 0  
Total other third party obligations payable 30 $ 35
Indemnification Agreement [Member]    
Litigation And Other Contingencies [Line Items]    
Total other third party obligations payable $ 64 $ 46