Property, Plant and Equipment Net (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
Cost:
Total cost	$ 62,150,629	$ 56,920,926
Less: Accumulated depreciation	(12,862,945)	(9,723,811)
Net book value	49,287,684	47,197,115
Buildings
Cost:
Total cost	35,030,328	34,264,012
Office equipment
Cost:
Total cost	424,849	415,007
Motor vehicles
Cost:
Total cost	768,254	696,015
Machinery
Cost:
Total cost	$ 25,927,198	$ 21,545,892