Inventories, Including Long-Term Mill and Leach Stockpiles (Unaudited) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Components of Inventories [Line Items]
Total materials and supplies, net	$ 1,610		$ 1,610		$ 1,649
Mill stockpiles, current	185		185		220
Leach stockpiles, current	819		819		923
Total current mill and leach stockpiles	1,004		1,004		1,143
Raw materials (primarily concentrate)	360		360		318
Work-in-process	163		163		124
Finished goods	755		755		839
Total product	1,278		1,278		1,281
Mill stockpiles, noncurrent	211		211		181
Leach stockpiles, noncurrent	1,252		1,252		1,244
Total long-term mill and leach stockpiles	1,463		1,463		1,425
Inventory obsolescence reserves	32		32		$ 24
Metals inventory adjustments	9	$ 41	92	$ 100
Metals
Components of Inventories [Line Items]
Metals inventory adjustments	$ 9
Inventory Write-down		$ 41	92	100
Copper
Components of Inventories [Line Items]
Inventory Write-down			58	41
Molybdenum
Components of Inventories [Line Items]
Inventory Write-down			$ 34
Cobalt
Components of Inventories [Line Items]
Inventory Write-down				$ 58