Property, Plant and Equipment (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Property, Plant and Equipment [Line Items]
Land	$ 34,493	$ 20,958
Buildings and building improvements	139,636	110,789
Machinery and equipment	254,544	231,094
Construction in progress	17,672	12,116
Property, Plant and Equipment, Gross	446,345	374,957
Less: accumulated depreciation	(250,982)	(240,819)
Property, Plant and Equipment, Net	$ 195,363	$ 134,138