Inventories, Including Long-Term Mill and Leach Stockpiles (Unaudited) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Components of Inventories [Line Items]
Total materials and supplies, net	$ 1,604		$ 1,604		$ 1,649
Mill stockpiles, current	166		166		220
Leach stockpiles, current	864		864		923
Total current mill and leach stockpiles	1,030		1,030		1,143
Raw materials (primarily concentrate)	287		287		318
Work-in-process	110		110		124
Finished goods	779		779		839
Total product	1,176		1,176		1,281
Mill stockpiles, noncurrent	207		207		181
Leach stockpiles, noncurrent	1,239		1,239		1,244
Total long-term mill and leach stockpiles	1,446		1,446		1,425
Inventory obsolescence reserves	31		31		$ 24
Metals inventory adjustments	(139)	$ 2	83	$ 59
Inventory Write-down		$ 2		$ 59
Metals
Components of Inventories [Line Items]
Metals inventory adjustments	139
Inventory Write-down			83
Copper
Components of Inventories [Line Items]
Metals inventory adjustments	144
Inventory Write-down			61
Molybdenum
Components of Inventories [Line Items]
Inventory Write-down	$ 5		$ 22