Goodwill and Other Intangibles - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Finite Lived Intangible Assets [Line Items]
Amortization of Intangible Assets	$ 0.3	$ 0.3	$ 0.5	$ 0.5
2018	0.5		0.5
2019	0.9		0.9
2020	0.9		0.9
2021	0.8		0.8
2022	$ 0.8		$ 0.8
Remaining amortization period			16 years 4 months 24 days
Patents [Member]
Finite Lived Intangible Assets [Line Items]
Remaining amortization period			7 years 6 months
Land Use Rights [Member]
Finite Lived Intangible Assets [Line Items]
Remaining amortization period			57 years 4 months 24 days
Trademarks [Member]
Finite Lived Intangible Assets [Line Items]
Remaining amortization period			8 years 10 months 24 days
Technology [Member]
Finite Lived Intangible Assets [Line Items]
Remaining amortization period			13 years 4 months 24 days
Customer Relationships [Member]
Finite Lived Intangible Assets [Line Items]
Remaining amortization period			11 years 10 months 24 days