2. Principal Accounting Policies (Detail) - Summary of Estimated Useful Lives for Significant Property, Plant, and Equipment	12 Months Ended
	Dec. 31, 2012
Buildings and Plant [Member] | Minimum [Member]
Property, Plant, and Equipment	20 years
Buildings and Plant [Member] | Maximum [Member]
Property, Plant, and Equipment	33 years
Machinery and Equipment [Member] | Minimum [Member]
Property, Plant, and Equipment	10 years
Machinery and Equipment [Member] | Maximum [Member]
Property, Plant, and Equipment	14 years
Office Equipment [Member]
Property, Plant, and Equipment	5 years
Automobiles [Member] | Minimum [Member]
Property, Plant, and Equipment	5 years
Automobiles [Member] | Maximum [Member]
Property, Plant, and Equipment	8 years