Property, Plant and Equipment, Net (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Property, Plant and Equipment
Property, Plant and Equipment, Net	$ 2,826	$ 3,102
Cameroon Africa [Member]
Property, Plant and Equipment
Property, Plant and Equipment, Gross	5,170	5,113
Less accumulated depreciation	(2,676)	(2,287)
Property, Plant and Equipment, Net	2,494	2,826
Cameroon Africa [Member] | Machinery and equipment [Member]
Property, Plant and Equipment
Property, Plant and Equipment, Gross	3,149	3,149
Cameroon Africa [Member] | Vehicles [Member]
Property, Plant and Equipment
Property, Plant and Equipment, Gross	1,081	1,012
Cameroon Africa [Member] | Buildings [Member]
Property, Plant and Equipment
Property, Plant and Equipment, Gross	413	412
Cameroon Africa [Member] | Furniture and equipment [Member]
Property, Plant and Equipment
Property, Plant and Equipment, Gross	527	526
Cameroon Africa [Member] | Equipment in transit [Member]
Property, Plant and Equipment
Property, Plant and Equipment, Gross		14
Other Projects [Member]
Property, Plant and Equipment
Property, Plant and Equipment, Gross	902	794
Less accumulated depreciation	(570)	(518)
Property, Plant and Equipment, Net	332	276
Other Projects [Member] | Machinery and equipment [Member]
Property, Plant and Equipment
Property, Plant and Equipment, Gross	144	115
Other Projects [Member] | Vehicles [Member]
Property, Plant and Equipment
Property, Plant and Equipment, Gross	38
Other Projects [Member] | Furniture and equipment [Member]
Property, Plant and Equipment
Property, Plant and Equipment, Gross	525	536
Other Projects [Member] | Equipment in transit [Member]
Property, Plant and Equipment
Property, Plant and Equipment, Gross	52
Other Projects [Member] | Other [Member]
Property, Plant and Equipment
Property, Plant and Equipment, Gross	$ 143	$ 143