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Property, Plant, and Equipment, at Cost (Tables) | 12 Months Ended
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Dec. 31, 2020
Property, Plant and Equipment [Abstract] |
Schedule Of Property, Plant, And Equipment, At Cost |
|  | December 31,
(in thousands) |  | 2020 |  | 2019
Land |  | $ | 37,796 |  |  | $ | 40,938 |
Land improvements |  | 58,646 |  |  | 57,635 |
Leasehold improvements |  | 2,146 |  |  | 2,122 |
Buildings |  | 183,234 |  |  | 174,600 |
Machinery and equipment |  | 1,188,396 |  |  | 1,161,409 |
Construction in progress |  | 73,234 |  |  | 29,228 |
|  | 1,543,452 |  |  | 1,465,932 |
Less accumulated depreciation and amortization |  | 878,305 |  |  | 830,493 |
Net property, plant, and equipment |  | $ | 665,147 |  |  | $ | 635,439 |
Schedule Of Useful Lives Of Property, Plant, And Equipment | We depreciate the cost of property, plant, and equipment by the straight-line method over the following estimated useful lives:
Land improvements | 9 - 40 years
Buildings | 10 - 46 years
Machinery and equipment | 3 - 30 years

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- Definition Tabular disclosure of useful lives of property, plant, and equipment, by type of asset. + References No definition available. + Details
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- Definition Tabular disclosure of physical assets used in the normal conduct of business and not intended for resale. Includes, but is not limited to, balances by class of assets, depreciation and depletion expense and method used, including composite depreciation, and accumulated deprecation. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(13)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229 + Details
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