Inventories, Including Long-Term Mill and Leach Stockpiles (Unaudited) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Components of Inventories [Line Items]
Total materials and supplies, net	$ 1,619		$ 1,619		$ 1,528
Mill stockpiles, current	200		200		282
Leach stockpiles, current	1,102		1,102		1,171
Total current mill and leach stockpiles	1,302		1,302		1,453
Raw materials (primarily concentrate)	292		292		260
Work-in-process	79		79		192
Finished goods	1,142		1,142		1,326
Total product	1,513		1,513		1,778
Mill stockpiles, noncurrent	223		223		265
Leach stockpiles, noncurrent	1,077		1,077		1,049
Total long-term mill and leach stockpiles	1,300		1,300		1,314
Inventory obsolescence reserves	26		26		$ 24
Inventory Write-down	$ 41	$ 0	100	$ 2
Cobalt
Components of Inventories [Line Items]
Inventory Write-down			58
Copper
Components of Inventories [Line Items]
Inventory Write-down			$ 41