XML 494 R110.htm IDEA: XBRL DOCUMENT v3.21.1
Income taxes - Carried forward tax credits (Details) - Net operating losses and tax carry forwards - USD ($)
$ in Millions
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Deferred tax assets and liabilities      
Deferred tax assets $ 5,106 $ 3,752 $ 3,779
Australia      
Deferred tax assets and liabilities      
Deferred tax assets 1,140    
United States      
Deferred tax assets and liabilities      
Deferred tax assets 956    
Canada      
Deferred tax assets and liabilities      
Deferred tax assets 1,101    
France      
Deferred tax assets and liabilities      
Deferred tax assets 900    
United Kingdom      
Deferred tax assets and liabilities      
Deferred tax assets 184    
Not later than one year      
Deferred tax assets and liabilities      
Deferred tax assets 69 71 90
Year 2      
Deferred tax assets and liabilities      
Deferred tax assets 26 48 70
Year 3      
Deferred tax assets and liabilities      
Deferred tax assets 7 27 38
Year 4      
Deferred tax assets and liabilities      
Deferred tax assets 2 19 32
Year 4 | Canada      
Deferred tax assets and liabilities      
Deferred tax assets 17    
Year 5 and after      
Deferred tax assets and liabilities      
Deferred tax assets 1,643 1,310 1,423
Year 5 and after | United States      
Deferred tax assets and liabilities      
Deferred tax assets 420    
Year 5 and after | Canada      
Deferred tax assets and liabilities      
Deferred tax assets 1,084    
Unlimited      
Deferred tax assets and liabilities      
Deferred tax assets 3,359 $ 2,277 $ 2,126
Unlimited | Australia      
Deferred tax assets and liabilities      
Deferred tax assets 1,140    
Unlimited | United States      
Deferred tax assets and liabilities      
Deferred tax assets 536    
Unlimited | France      
Deferred tax assets and liabilities      
Deferred tax assets 900    
Unlimited | United Kingdom      
Deferred tax assets and liabilities      
Deferred tax assets $ 184