Goodwill and Other Intangible Assets - Goodwill, by Reportable Segment (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Goodwill [Line Items]
Goodwill impairment	$ 0	$ 0	$ 0	$ 0
Accumulated goodwill impairment	1,400,000		1,400,000		$ 1,400,000
Goodwill [Roll Forward]
Balance			535,100,000
Foreign currency translation adjustments			(7,300,000)
Balance	527,800,000		527,800,000
Corporate [Member]
Goodwill [Roll Forward]
Balance			0
Foreign currency translation adjustments			0
Balance	0		0
Advanced Plastic Processing Technologies | Segments [Member]
Goodwill [Roll Forward]
Balance			35,600,000
Foreign currency translation adjustments			0
Balance	35,600,000		35,600,000
Melt Delivery and Control Systems | Segments [Member]
Goodwill [Roll Forward]
Balance			452,600,000
Foreign currency translation adjustments			(7,300,000)
Balance	445,300,000		445,300,000
Fluid Technologies | Segments [Member]
Goodwill [Roll Forward]
Balance			46,900,000
Foreign currency translation adjustments			0
Balance	$ 46,900,000		$ 46,900,000