Property, Plant and Equipment, Net (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Property, Plant and Equipment, Net
Property, plant and equipment, gross	$ 468,153
Property, plant and equipment, gross		$ 436,256
Accumulated depreciation and amortization	(236,578)
Accumulated depreciation and amortization		(207,868)
Property, plant and equipment, net	231,575
Property, plant and equipment, net		228,388
Software development cost capitalized
Software development cost capitalized	11,800	4,100	$ 3,100
Depreciation and amortization
Amortization expense, capitalized software and development	6,600	6,300	6,400
Total depreciation and amortization expense	43,002	40,496	40,871
Property, plant and equipment
Depreciation and amortization
Total depreciation and amortization expense	32,400	32,200	31,600
Land
Property, Plant and Equipment, Net
Property, plant and equipment, gross	14,551
Property, plant and equipment, gross		14,515
Buildings and improvements
Property, Plant and Equipment, Net
Property, plant and equipment, gross	146,727
Property, plant and equipment, gross		142,113
Machinery and equipment
Property, Plant and Equipment, Net
Property, plant and equipment, gross	171,230
Property, plant and equipment, gross		160,707
Furniture, computers and equipment
Property, Plant and Equipment, Net
Property, plant and equipment, gross	40,143
Property, plant and equipment, gross		36,405
Computer software
Property, Plant and Equipment, Net
Property, plant and equipment, gross	70,458
Property, plant and equipment, gross		62,517
Construction in progress
Property, Plant and Equipment, Net
Property, plant and equipment, gross	25,044
Property, plant and equipment, gross		19,999
Software development cost capitalized
Software development cost capitalized	4,600	2,400	700
Software placed into service
Software development cost capitalized
Software development cost capitalized	$ 7,200	$ 1,700	$ 2,400