Inventories, Including Long-Term Mill and Leach Stockpiles (Unaudited) (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Components of Inventories [Line Items]
Total materials and supplies, net	[1]	$ 1,348		$ 1,348		$ 1,594
Total current mill and leach stockpiles		1,312		1,312		1,539
Raw materials (primarily concentrate)		209		209		220
Work-in-process		94		94		108
Finished goods		722		722		743
Total product inventories		1,025		1,025		1,071
Total long-term mill and leach stockpiles		1,723		1,723		1,663
Inventory obsolescence reserves		31		31		26
Mining inventory adjustments		(20)	$ (91)	(27)	$ (154)
Current [Member]
Components of Inventories [Line Items]
Mill stockpiles		172		172		137
Leach stockpiles		1,140		1,140		1,402
Total current mill and leach stockpiles		1,312		1,312		1,539
Long-Term [Member]
Components of Inventories [Line Items]
Mill stockpiles		580		580		480
Leach stockpiles		1,143		1,143		1,183
Total long-term mill and leach stockpiles	[2]	$ 1,723		$ 1,723		$ 1,663

[1] Materials and supplies inventory was net of obsolescence reserves totaling $31 million at September 30, 2016, and $26 million at December 31, 2015.

[2] Estimated metals in stockpiles not expected to be recovered within the next 12 months.