Summary of Property and Equipment (Detail) - USD ($)	Sep. 30, 2015	Dec. 31, 2014
Property, Plant and Equipment [Line Items]
Buildings	$ 2,414,381	$ 2,496,012
Plant and machinery	18,891,758	19,502,409
Motor vehicles	55,105	37,097
Office and electric equipment	642,141	652,268
Subtotal	22,003,385	22,687,786
Less: accumulated depreciation	(13,832,384)	(13,297,528)
Property and equipment, net	$ 8,171,001	$ 9,390,258