PROPERTY, PLANT, EQUIPMENT AND MINING DEVELOPMENT COSTS, NET (Schedule of PPE) (Details) - USD ($)	12 Months Ended					132 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 30, 2008	Dec. 31, 2007	Dec. 31, 2017
Property, Plant and Equipment [Line Items]
Property, plant, equipment and mining development costs	$ 71,105,000,000	$ 64,796,000,000				$ 64,796,000,000
Accumulated depreciation, depletion and amortization	(43,095,000,000)	(41,802,000,000)				(41,802,000,000)
Property, plant, equipment and mining development costs, net	28,010,000,000	22,994,000,000				22,994,000,000
Proven and probable reserves [Member]
Property, Plant and Equipment [Line Items]
Property, plant, equipment and mining development costs	7,089,000,000	3,974,000,000				3,974,000,000
Transfer From Value Beyond Proven And Probable Reserves To Proven And Probable Reserves	59,000,000	112,000,000				752,000,000
Value beyond proven and probable reserves (VBPP) [Member]
Property, Plant and Equipment [Line Items]
Payments to Acquire Mineral Rights					$ 1,700,000,000
Property, plant, equipment and mining development costs	477,000,000	536,000,000				536,000,000
Property, Plant and Equipment, Transfers and Changes				$ 485,000,000
Mine development and other
Property, Plant and Equipment [Line Items]
Property, plant, equipment and mining development costs	8,195,000,000	6,213,000,000				6,213,000,000
Buildings and infrastructure
Property, Plant and Equipment [Line Items]
Property, plant, equipment and mining development costs	8,051,000,000	7,553,000,000				7,553,000,000
Machinery and equipment
Property, Plant and Equipment [Line Items]
Property, plant, equipment and mining development costs	12,985,000,000	12,330,000,000				12,330,000,000
Mobile equipment
Property, Plant and Equipment [Line Items]
Property, plant, equipment and mining development costs	4,010,000,000	3,766,000,000				3,766,000,000
Construction in progress
Property, Plant and Equipment [Line Items]
Property, plant, equipment and mining development costs	3,006,000,000	2,971,000,000				2,971,000,000
Oil and Gas Properties [Member]
Property, Plant and Equipment [Line Items]
Property, plant, equipment and mining development costs	27,292,000,000	27,453,000,000				27,453,000,000
Accumulated depreciation, depletion and amortization	(27,300,000,000)	(27,400,000,000)				$ (27,400,000,000)
Discontinued Operations
Property, Plant and Equipment [Line Items]
Payments to Acquire Mineral Rights					$ 544,000,000
Mining Operations [Member]
Property, Plant and Equipment [Line Items]
Capitalized interest	96,000,000	$ 121,000,000	$ 92,000,000
PT Rio Tinto Indonesia [Domain] | Proven and probable reserves [Member]
Property, Plant and Equipment [Line Items]
Property, plant, equipment and mining development costs	$ 4,600,000,000