Property, Plant And Equipment (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Property, Plant and Equipment, Net [Abstract]
Property, Plant and Equipment at Cost	$ 496,430	$ 473,832
Accumulated Depreciation	(240,092)	(221,701)
Property, Plant and Equipment Net Book Value	256,338	252,131
Wassa/HBB
Property, Plant and Equipment, Net [Abstract]
Property, Plant and Equipment at Cost	117,090	106,631
Accumulated Depreciation	(62,051)	(52,430)
Property, Plant and Equipment Net Book Value	55,039	54,201
Corporate and Other [Member]
Property, Plant and Equipment, Net [Abstract]
Property, Plant and Equipment at Cost	1,346	1,378
Accumulated Depreciation	(908)	(879)
Property, Plant and Equipment Net Book Value	438	499
Bogoso/Prestea | Bogoso/Prestea
Property, Plant and Equipment, Net [Abstract]
Property, Plant and Equipment at Cost	182,842	179,216
Accumulated Depreciation	(112,135)	(109,519)
Property, Plant and Equipment Net Book Value	70,707	69,697
Bogoso Refactory Plant | Bogoso/Prestea
Property, Plant and Equipment, Net [Abstract]
Property, Plant and Equipment at Cost	195,152	186,607
Accumulated Depreciation	(64,998)	(58,873)
Property, Plant and Equipment Net Book Value	$ 130,154	$ 127,734