BUSINESS SEGMENTS - Additional Financial Information (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Segment Reporting, Other Significant Reconciling Item [Line Items]
Depreciation, depletion and amortization	$ 521	$ 565	$ 479
Net pension and postretirement cost (credit)(1)	97	(13)	25
Charges for integration and restructuring, closures and asset impairments (Note 17)	194	170	39
Equity earnings (loss) from joint ventures	1	22	0
Capital expenditures	419	425	365
Investments in and advances to joint ventures	31	56	0
Operating segments \| Timberlands
Segment Reporting, Other Significant Reconciling Item [Line Items]
Depreciation, depletion and amortization	356	366	208
Net pension and postretirement cost (credit)(1)	7	8	9
Charges for integration and restructuring, closures and asset impairments (Note 17)	147	0	0
Equity earnings (loss) from joint ventures	0	0	0
Capital expenditures	115	116	75
Investments in and advances to joint ventures	0	0	0
Operating segments \| RE & ENR
Segment Reporting, Other Significant Reconciling Item [Line Items]
Depreciation, depletion and amortization	15	13	1
Net pension and postretirement cost (credit)(1)	1	0	0
Charges for integration and restructuring, closures and asset impairments (Note 17)	0	15	0
Equity earnings (loss) from joint ventures	1	2	0
Capital expenditures	2	1	0
Investments in and advances to joint ventures			0
Operating segments \| Wood Products
Segment Reporting, Other Significant Reconciling Item [Line Items]
Depreciation, depletion and amortization	145	129	106
Net pension and postretirement cost (credit)(1)	23	22	27
Charges for integration and restructuring, closures and asset impairments (Note 17)	13	7	10
Equity earnings (loss) from joint ventures	0	0	0
Capital expenditures	299	297	287
Investments in and advances to joint ventures	0	0	0
Unallocated Items
Segment Reporting, Other Significant Reconciling Item [Line Items]
Depreciation, depletion and amortization	5	4	10
Net pension and postretirement cost (credit)(1)	66	(43)	(11)
Charges for integration and restructuring, closures and asset impairments (Note 17)	34	148	29
Equity earnings (loss) from joint ventures	0	20	0
Capital expenditures	3	11	3
Investments in and advances to joint ventures	$ 0	0	0
Continuing operations
Segment Reporting, Other Significant Reconciling Item [Line Items]
Depreciation, depletion and amortization		$ 512	$ 325

The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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