Other Financial Statement Information - Property, Plant and Equipment - Net (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Property, Plant and Equipment [Line Items]
Property, plant and equipment - Gross	$ 261,702	$ 261,205
Less accumulated depreciation	(158,747)	(152,607)
Property, plant and equipment - Net	102,955	108,598
Land and Improvements [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment - Gross	12,552	13,141
Buildings and Improvements [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment - Gross	74,743	75,941
Machinery, Equipment and Aircraft [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment - Gross	171,015	166,999
Construction in Progress [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment - Gross	$ 3,392	$ 5,124