Property and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Summary of property and equipment
Property and equipment, gross	$ 46,176	$ 43,997
Less: accumulated depreciation	(23,482)	(22,091)
Property and equipment, net	22,694	21,906
Property and plant [Member]
Summary of property and equipment
Property and equipment, gross	23,259	18,343
Leasehold improvements [Member]
Summary of property and equipment
Property and equipment, gross	15,844	17,232
Construction-in-progress [Member]
Summary of property and equipment
Property and equipment, gross	16	1,283
Equipment and machinery [Member]
Summary of property and equipment
Property and equipment, gross	2,603	2,882
Office equipment and furniture [Member]
Summary of property and equipment
Property and equipment, gross	3,340	3,105
Motor vehicles [Member]
Summary of property and equipment
Property and equipment, gross	$ 1,114	$ 1,152