CHARGES FOR INTEGRATION AND RESTRUCTURING, CLOSURES AND ASSET IMPAIRMENTS Items Included in Our Integration and Restructuring, Closure and Asset Impairment Charges (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Charges related to integration and restructuring
Impairments of long-lived assets	$ 0	$ 147	$ 1	$ 147
Total charges for integration and restructuring, closures and asset impairments	0	151	2	164
Plum Creek
Charges related to integration and restructuring
Integration and restructuring charges related to our merger with Plum Creek	0	2	0	14
Other
Charges related to integration and restructuring
Charges related to closures and other restructuring activities	$ 0	$ 2	$ 1	$ 3

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 45
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=68055307&loc=d3e2420-110228

Reference 2: 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

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Costs incurred to effect a business combination which have been expensed during the period. Such costs could include business integration costs, systems integration and conversion costs, and severance and other employee-related costs.

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Amount of restructuring charges, remediation cost, and asset impairment loss.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.3)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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Other Closures and Restructuring Costs

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