Property, Plant And Equipment (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Property, Plant and Equipment, Net [Abstract]
Property, Plant and Equipment at Cost	$ 488,494	$ 473,832
Accumulated Depreciation	(232,584)	(221,701)
Property, Plant and Equipment Net Book Value	255,910	252,131
Wassa/HBB
Property, Plant and Equipment, Net [Abstract]
Property, Plant and Equipment at Cost	111,635	106,631
Accumulated Depreciation	(58,611)	(52,430)
Property, Plant and Equipment Net Book Value	53,024	54,201
Corporate and Other [Member]
Property, Plant and Equipment, Net [Abstract]
Property, Plant and Equipment at Cost	1,348	1,378
Accumulated Depreciation	(891)	(879)
Property, Plant and Equipment Net Book Value	457	499
Bogoso/Prestea | Bogoso/Prestea
Property, Plant and Equipment, Net [Abstract]
Property, Plant and Equipment at Cost	182,294	179,216
Accumulated Depreciation	(109,972)	(109,519)
Property, Plant and Equipment Net Book Value	72,322	69,697
Bogoso Refactory Plant | Bogoso/Prestea
Property, Plant and Equipment, Net [Abstract]
Property, Plant and Equipment at Cost	193,217	186,607
Accumulated Depreciation	(63,110)	(58,873)
Property, Plant and Equipment Net Book Value	$ 130,107	$ 127,734