Estimated Useful Lives of Assets (Detail)	9 Months Ended
	Sep. 30, 2012
Buildings | Minimum
Property, Plant and Equipment [Line Items]
Property plant and equipment, estimated useful lives	5 years
Buildings | Maximum
Property, Plant and Equipment [Line Items]
Property plant and equipment, estimated useful lives	20 years
Machinery | Minimum
Property, Plant and Equipment [Line Items]
Property plant and equipment, estimated useful lives	5 years
Machinery | Maximum
Property, Plant and Equipment [Line Items]
Property plant and equipment, estimated useful lives	10 years
Office equipment & motor vehicles
Property, Plant and Equipment [Line Items]
Property plant and equipment, estimated useful lives	5 years