Property, Plant and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Property plant and equipment
Gross property, plant and equipment	$ 1,290,669	$ 1,395,226
Less accumulated depreciation	(904,080)	(931,399)
Net property, plant and equipment	386,589	463,827
Land
Property plant and equipment
Gross property, plant and equipment	41,425	42,854
Buildings
Property plant and equipment
Gross property, plant and equipment	248,289	265,369
Building and leasehold improvements
Property plant and equipment
Gross property, plant and equipment	137,039	150,613
Machinery and equipment
Property plant and equipment
Gross property, plant and equipment	731,198	804,252
Furniture and fixtures
Property plant and equipment
Gross property, plant and equipment	114,230	117,271
Assets under development
Property plant and equipment
Gross property, plant and equipment	$ 18,488	$ 14,867

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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