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Gains (Losses) on Dispositions of Plant, Equipment and Timberlands (Summary for Sale of Timberlands and Other Assets) (Detail) $ in Thousands | 3 Months Ended
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Mar. 31, 2018 USD ($) a | Mar. 31, 2017 USD ($)
Property, Plant and Equipment [Line Items] |  |
Proceeds | $ 1,695 |
Gain (loss) | $ 1,554 | $ (32)
Timberlands [Member] |  |
Property, Plant and Equipment [Line Items] |  |
Acres | a | 426 |
Proceeds | $ 1,156 |
Gain (loss) | 1,115 |
Other [Member] |  |
Property, Plant and Equipment [Line Items] |  |
Proceeds | 539 |
Gain (loss) | $ 439 | $ (32)

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- Definition Area of land held. + References No definition available. + Details
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- Definition Amount of gain (loss) on sale or disposal of property, plant and equipment assets, including oil and gas property and timber property. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585 + Details
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- Definition The cash inflow from the sale of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 12 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3179-108585 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Details
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- Details
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