Basis of Presentation and Summary of Significant Accounting Policies - Property, Plant and Equipment by Geographic Location (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Property, Plant and Equipment [Line Items]
Property, plant and equipment, net	$ 272,600,000	$ 279,800,000
Impairment of long-lived assets	0	0	$ 0
U.S.
Property, Plant and Equipment [Line Items]
Property, plant and equipment, net	156,900,000	151,900,000
Western Europe
Property, Plant and Equipment [Line Items]
Property, plant and equipment, net	76,600,000	82,800,000
Developing
Property, Plant and Equipment [Line Items]
Property, plant and equipment, net	28,800,000	33,000,000
Other Developed
Property, Plant and Equipment [Line Items]
Property, plant and equipment, net	$ 10,300,000	$ 12,100,000