XML 181 R93.htm IDEA: XBRL DOCUMENT v3.20.1
Income Taxes - Additional Information (Detail) - CAD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2022
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Disclosure Of Temporary Difference Unused Tax Losses And Unused Tax Credits [Line Items]        
Change in provincial corporate income tax rate   12.00%    
US federal corporate tax rate     21.00% 35.00%
Unrecognized tax benefits     $ 2  
Interest and penalties included in unrecognized tax benefits     1  
U.S. and international operations [Member]        
Disclosure Of Temporary Difference Unused Tax Losses And Unused Tax Credits [Line Items]        
Loss carryforwards not recognized as deferred income tax asset   $ 31    
Canada [Member]        
Disclosure Of Temporary Difference Unused Tax Losses And Unused Tax Credits [Line Items]        
Loss carryforwards not recognized as deferred income tax asset   33    
Temporary differences [Member] | International operations [Member]        
Disclosure Of Temporary Difference Unused Tax Losses And Unused Tax Credits [Line Items]        
Tax effected temporary differences   $ 5    
Temporary differences [Member] | U.S. and international operations [Member]        
Disclosure Of Temporary Difference Unused Tax Losses And Unused Tax Credits [Line Items]        
Tax effected temporary differences     $ 37  
Changes in tax rates or tax laws enacted or announced [Member]        
Disclosure Of Temporary Difference Unused Tax Losses And Unused Tax Credits [Line Items]        
Change in provincial corporate income tax rate 8.00%