Property, Plant And Equipment (Tables)

12 Months Ended

Dec. 31, 2018

Property Plant And Equipment [Abstract]

Schedule Of Property, Plant And Equipment

			December 31,
(in thousands)			2018		2017
	Land	$	6,169	$	6,169
	Buildings and building improvements		97,103		90,577
	Machinery and equipment		514,450		476,466
	Furniture and fixtures		9,343		8,468
	Vehicles		1,341		1,244
	Leasehold improvements		30,122		25,153
	Construction in progress		13,134		10,439
			671,662		618,516
	Less accumulated depreciation		(460,708)		(432,043)
		$	210,954	$	186,473