XML 306 R101.htm IDEA: XBRL DOCUMENT v3.19.3.a.u2
Operating segments - Summary of gross sales revenue within the reportable segments (Detail) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Disclosure of operating segments [Line Items]      
Consolidated sales revenue $ 43,165 $ 40,522 $ 40,030
Reportable segments [Member]      
Disclosure of operating segments [Line Items]      
Consolidated sales revenue 45,398 42,850 41,872
Reportable segments [Member] | Iron ore [Member]      
Disclosure of operating segments [Line Items]      
Consolidated sales revenue 24,075 18,731 18,466
Reportable segments [Member] | Aluminium [Member]      
Disclosure of operating segments [Line Items]      
Consolidated sales revenue 10,340 12,191 11,005
Reportable segments [Member] | Copper & Diamonds [Member]      
Disclosure of operating segments [Line Items]      
Consolidated sales revenue 5,815 6,468 4,842
Reportable segments [Member] | Energy & Minerals [Member]      
Disclosure of operating segments [Line Items]      
Consolidated sales revenue 5,150 5,451 7,549
Reportable segments [Member] | Other operations [Member]      
Disclosure of operating segments [Line Items]      
Consolidated sales revenue 18 9 10
Inter-segment transactions [Member]      
Disclosure of operating segments [Line Items]      
Consolidated sales revenue (31) (15) (15)
Product group [Member]      
Disclosure of operating segments [Line Items]      
Consolidated sales revenue 45,367 42,835 41,857
Items excluded from underlying earnings [Member]      
Disclosure of operating segments [Line Items]      
Consolidated sales revenue 0 0 10
Gross sales revenue [Member]      
Disclosure of operating segments [Line Items]      
Consolidated sales revenue 45,367 42,835 41,867
Share of equity accounted units and adjustments [Member]      
Disclosure of operating segments [Line Items]      
Sales revenue $ (2,202) $ (2,313) $ (1,837)