Property, Plant and Equipment (Details Textual) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Property, Plant and Equipment [Line Items]
Depreciation expense	$ 561	$ 395
Interest costs capitalized	1,348	485
Construction in progress
Property, Plant and Equipment [Line Items]
Interest costs capitalized	1,300	500
Payroll costs	$ 400	$ 100