Property, Plant and Equipment (Tables)

3 Months Ended

Mar. 31, 2021

Property Plant And Equipment [Abstract]

Schedule of Property, Plant and Equipment

	March 31, 2021			December 31, 2020
(Dollars in thousands)
Land and buildings	$	144,491		$	149,295
Machinery and equipment		867,347			899,764
Leasehold improvements and others		14,470			14,912
Construction in progress		41,549			46,718
		1,067,857			1,110,689
Accumulated depreciation		(571,198	)		(588,565	)
Property, plant and equipment, net	$	496,659		$	522,124