Property, plant and equipment, net (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Total property, plant and equipment	$ 667,147		$ 667,147		$ 676,347
Less: accumulated depreciation	(220,173)		(220,173)		(200,772)
Property, plant and equipment, net	446,974		446,974		475,575
Depreciation expense	12,100	$ 12,400	24,300	$ 25,200
Machinery and equipment
Property, Plant and Equipment [Line Items]
Total property, plant and equipment	410,007		410,007		398,127
Land, buildings and improvements
Property, Plant and Equipment [Line Items]
Total property, plant and equipment	233,155		233,155		240,403
Other equipment
Property, Plant and Equipment [Line Items]
Total property, plant and equipment	11,781		11,781		8,660
Construction-in-progress
Property, Plant and Equipment [Line Items]
Total property, plant and equipment	$ 12,204		$ 12,204		$ 29,157