Property, Plant and Equipment (Tables)

9 Months Ended

12 Months Ended

Sep. 30, 2018

Dec. 31, 2017

Property, Plant and Equipment [Abstract]

Components of property, plant and equipment, net

Property, plant and equipment consisted of the following:

(in thousands)	September 30, 2018			December 31, 2017
Land	$	13,623		$	13,557
Buildings and improvements		104,026			99,233
Machinery, equipment and other		501,148			446,261
		618,797			559,051
Accumulated depreciation		(382,730	)		(347,219	)
Property, plant and equipment, net	$	236,067		$	211,832

The components of property, plant and equipment, net were as follows:

	December 31, 2017			December 31, 2016
Land	$	13,557		$	14,636
Buildings and improvements		99,233			91,927
Machinery, equipment and other		446,261			396,505
Property, plant and equipment, gross		559,051			503,068
Total accumulated depreciation		(347,219	)		(301,321	)
Property, plant and equipment, net	$	211,832		$	201,747