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Gain on Dispositions of Plant, Equipment and Timberlands - Summary for Sale of Timberlands and Other Assets (Detail) $ in Thousands | 12 Months Ended
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Dec. 31, 2016 USD ($) | Dec. 31, 2015 USD ($) a | Dec. 31, 2014 USD ($) a
Property, Plant and Equipment [Line Items] |  |  |
Proceeds | $ 70 | $ 24,459 | $ 5,072
Gain (loss) | (216) | 21,113 | 4,861
Other [Member] |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Proceeds | 70 | 542 | 10
Gain (loss) | $ (216) | $ 246 | $ 6
Timberlands [Member] |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Acres | a |  | 15,628 | 2,753
Proceeds |  | $ 23,917 | $ 5,062
Gain (loss) |  | $ 20,867 | $ 4,855

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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=66902209&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=66902209&loc=d3e3179-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Investing Activities -URI http://asc.fasb.org/extlink&oid=6516133 + 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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