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Gains on Dispositions of Plant, Equipment and Timberlands (Summary for Sale of Timberlands and Other Assets) (Detail) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2018 USD ($) a | Sep. 30, 2017 USD ($) a | Sep. 30, 2018 USD ($) a | Sep. 30, 2017 USD ($) a
Property, Plant and Equipment [Line Items] |  |  |  |
Proceeds |  |  | $ 2,073 | $ 209
Gain (loss) | $ 249 | $ 93 | $ 1,939 | $ 168
Timberlands [Member] |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |
Acres | a | 1,103 | 332 | 1,103 | 332
Proceeds |  |  | $ 2,046 | $ 209
Gain (loss) |  |  | 1,929 | 188
Other [Member] |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |
Proceeds |  |  | 27 |
Gain (loss) |  |  | $ 10 | $ (20)

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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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109223946&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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 12 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=109223946&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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