Property, Plant and Equipment - (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Property, plant and equipment
Property, Plant and Equipment	$ 696,538				$ 661,791				$ 696,538	$ 661,791
Accumulated depreciation	(175,531)				(138,372)				(175,531)	(138,372)
Property plant and equipment net excluding construction in progress	521,007				523,419				521,007	523,419
Construction in process	66,390				76,055				66,390	76,055
Total	587,397				599,474				587,397	599,474
Impairment of property, plant and equipment	48,532	$ 0	$ 1,341	$ 0	17,893	$ 0	$ 0	$ 0	49,873	17,893	$ 0
New Orleans
Property, plant and equipment
Impairment of property, plant and equipment	44,649								44,649
Emporia
Property, plant and equipment
Impairment of property, plant and equipment										15,593
Land
Property, plant and equipment
Property, Plant and Equipment	10,480				5,412				10,480	5,412
Buildings and improvements
Property, plant and equipment
Property, Plant and Equipment	140,261				134,398				140,261	134,398
Leasehold improvements
Property, plant and equipment
Property, Plant and Equipment	10,806				10,520				10,806	10,520
Machinery and equipment
Property, plant and equipment
Property, Plant and Equipment	$ 534,991				$ 511,461				$ 534,991	$ 511,461