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v3.21.2

Property, Plant and Equipment, net (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2021 | Sep. 30, 2020 | Sep. 30, 2021 | Sep. 30, 2020 | Dec. 31, 2020
Property, Plant and Equipment, net |  |  |  |  |
Property, plant and equipment, gross | $ 294,952 |  | $ 294,952 |  | $ 282,688
Accumulated depreciation and amortization | (204,586) |  | (204,586) |  | (190,007)
Property, plant and equipment, net | 90,366 |  | 90,366 |  | 92,681
Depreciation expense | 6,100 | $ 6,200 | 18,400 | $ 18,300 |
Land |  |  |  |  |
Property, Plant and Equipment, net |  |  |  |  |
Property, plant and equipment, gross | 2,776 |  | 2,776 |  | 2,724
Buildings and improvements |  |  |  |  |
Property, Plant and Equipment, net |  |  |  |  |
Property, plant and equipment, gross | 25,057 |  | $ 25,057 |  | 25,731
Buildings and improvements | Minimum |  |  |  |  |
Property, Plant and Equipment, net |  |  |  |  |
Useful Life (Years) |  |  | 30 years |  |
Buildings and improvements | Maximum |  |  |  |  |
Property, Plant and Equipment, net |  |  |  |  |
Useful Life (Years) |  |  | 40 years |  |
Office furniture and equipment |  |  |  |  |
Property, Plant and Equipment, net |  |  |  |  |
Property, plant and equipment, gross | 20,697 |  | $ 20,697 |  | 19,902
Office furniture and equipment | Minimum |  |  |  |  |
Property, Plant and Equipment, net |  |  |  |  |
Useful Life (Years) |  |  | 5 years |  |
Office furniture and equipment | Maximum |  |  |  |  |
Property, Plant and Equipment, net |  |  |  |  |
Useful Life (Years) |  |  | 8 years |  |
Machinery and equipment |  |  |  |  |
Property, Plant and Equipment, net |  |  |  |  |
Property, plant and equipment, gross | $ 246,422 |  | $ 246,422 |  | $ 234,331
Machinery and equipment | Minimum |  |  |  |  |
Property, Plant and Equipment, net |  |  |  |  |
Useful Life (Years) |  |  | 5 years |  |
Machinery and equipment | Maximum |  |  |  |  |
Property, Plant and Equipment, net |  |  |  |  |
Useful Life (Years) |  |  | 7 years |  |

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