Inventories, Including Long-Term Mill and Leach Stockpiles (Unaudited) Mill and Leach Stockpiles (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2012		Dec. 31, 2011
Mill and Leach Stockpiles [Line Items]
Current mill and leach stockpiles	$ 1,595		$ 1,289
Total long-term mill and leach stockpiles	1,871		1,686
Current [Member]
Mill and Leach Stockpiles [Line Items]
Mill Stockpiles	97		69
Leach stockpiles	1,498		1,220
Current mill and leach stockpiles	1,595		1,289
Long-Term [Member]
Mill and Leach Stockpiles [Line Items]
Mill Stockpiles	595	[1]	535	[1]
Leach stockpiles	1,276	[1]	1,151	[1]
Total long-term mill and leach stockpiles	$ 1,871	[1]	$ 1,686	[1]

[1] Metals in stockpiles not expected to be recovered within the next 12 months.