Property Plant and Equipment, Net (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 439,836	$ 350,999
Less accumulated depreciation	(228,984)	(210,549)
Property, plant and equipment, net	210,852	140,450
Depreciation	28,000	21,300	$ 20,900
Land
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	36,683	16,319
Buildings
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	134,995	101,562
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	15,590	14,904
Machinery, office furniture and equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	241,027	200,466
Construction in process
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	11,541	17,748
Assets Held under Finance Leases [Member]
Property, Plant and Equipment [Line Items]
Depreciation	900	900	$ 700
Finance Lease Assets, Gross	6,700	10,900
Finance Leases, Lessee Balance Sheet, Assets by Major Class, Accumulated Depreciation	$ 2,100	$ 2,400