PROPERTY, PLANT, EQUIPMENT AND MINING DEVELOPMENT COSTS, NET (Schedule of PPE) (Details) - USD ($)	12 Months Ended					156 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 30, 2008	Dec. 31, 2007	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Property, plant, equipment and mining development costs	$ 73,357,000,000	$ 71,105,000,000				$ 73,357,000,000
Accumulated depreciation, depletion and amortization	(43,773,000,000)	(43,095,000,000)				(43,773,000,000)
Property, plant, equipment and mining development costs, net	29,584,000,000	28,010,000,000				29,584,000,000
Proven and probable reserves [Member]
Property, Plant and Equipment [Line Items]
Property, plant, equipment and mining development costs	7,087,000,000	7,089,000,000				7,087,000,000
Transfer From Value Beyond Proven And Probable Reserves To Proven And Probable Reserves	0	59,000,000				811,000,000
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	465,000,000	477,000,000				465,000,000
Property, Plant and Equipment, Transfers and Changes				$ 497,000,000
Mine development and other
Property, Plant and Equipment [Line Items]
Property, plant, equipment and mining development costs	8,180,000,000	8,195,000,000				8,180,000,000
Buildings and infrastructure
Property, Plant and Equipment [Line Items]
Property, plant, equipment and mining development costs	8,435,000,000	8,051,000,000				8,435,000,000
Machinery and equipment
Property, Plant and Equipment [Line Items]
Property, plant, equipment and mining development costs	13,312,000,000	12,985,000,000				13,312,000,000
Mobile equipment
Property, Plant and Equipment [Line Items]
Property, plant, equipment and mining development costs	4,320,000,000	4,010,000,000				4,320,000,000
Construction in progress
Property, Plant and Equipment [Line Items]
Property, plant, equipment and mining development costs	4,265,000,000	3,006,000,000				4,265,000,000
Oil and Gas Properties [Member]
Property, Plant and Equipment [Line Items]
Property, plant, equipment and mining development costs	27,293,000,000	27,292,000,000				27,293,000,000
Accumulated depreciation, depletion and amortization	(27,300,000,000)	(27,300,000,000)				$ (27,300,000,000)
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	$ 149,000,000	$ 96,000,000	$ 121,000,000