Gains on Disposition of Plant, Equipment and Timberlands (Summary for Sale of Timberlands and Other Assets Included in Continuing Operations) (Detail) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019 USD ($) a	Jun. 30, 2018 USD ($) a	Jun. 30, 2019 USD ($) a	Jun. 30, 2018 USD ($) a
Property, Plant and Equipment [Line Items]
Proceeds			$ 1,116	$ 1,804
Gain	$ 423	$ 574	$ 1,092	$ 1,690
Timberlands [Member]
Property, Plant and Equipment [Line Items]
Acres \| a	361	1,029	361	1,029
Proceeds			$ 902	$ 1,785
Gain			881	1,680
Other [Member]
Property, Plant and Equipment [Line Items]
Proceeds			214	19
Gain			$ 211	$ 10

Area of land held.

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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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- Details

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