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RELATED PARTIES - Additional Information (Details) $ in Millions		3 Months Ended		6 Months Ended	12 Months Ended
	Apr. 01, 2016 USD ($) a	Dec. 31, 2017 USD ($) a	Sep. 30, 2016 USD ($)	Aug. 30, 2016	Dec. 31, 2020	Dec. 31, 2017 USD ($) a Rate	Dec. 31, 2016 USD ($) Rate	Dec. 31, 2015 USD ($)
Related Party Transaction [Line Items]
Increase (Decrease) in Restricted Cash and Investments						$ (25)	$ (46)	$ 0
Proceeds from Equity Method Investment, Distribution, Return of Capital						1	14	15
Net gains on sale of nonstrategic assets						(16)	(73)	(38)
Proceeds from sale of Southern timberlands						203	0	0
Proceeds from contribution of timberlands to related party (Note 8)						0	440	0
Proceeds from redemption of ownership interest in related party						108	0	0
Interest expense						$ 393	431	341
Real Estate Development Ventures
Related Party Transaction [Line Items]
Expiration of joint venture agreement					2020
Timberland Venture
Related Party Transaction [Line Items]
Gain on redemption of debt instrument			$ 6
Twin Creeks Venture
Related Party Transaction [Line Items]
Sale of Timberland acreage \| a		100,000				100,000
Net gains on sale of nonstrategic assets		$ (99)
Proceeds from sale of Southern timberlands		$ 203
Contributed acres of timberlands to venture \| a	260,000
Agreed-upon value of acres contributed	$ 560
Proceeds from contribution of timberlands to related party (Note 8)	$ 440
Ownership interest						21.00%
Proceeds from redemption of ownership interest in related party						$ 108
Other partner ownership interest		79.00%				79.00%
Guaranteed annual return						3.00%
Percentage of profit in excess of guaranteed annual return						75.00%
Twin Creeks Venture \| Georgia
Related Party Transaction [Line Items]
Sale of Timberland acreage \| a		20,000				20,000
Twin Creeks Venture \| Mississippi
Related Party Transaction [Line Items]
Sale of Timberland acreage \| a		80,000				80,000
Class A Properties \| Real Estate Development Ventures
Related Party Transaction [Line Items]
Equity method investment, ownership percentage		3.00%				3.00%
Other partner ownership percentage		97.00%				97.00%
Class B Properties \| Real Estate Development Ventures
Related Party Transaction [Line Items]
Equity method investment, ownership percentage		50.00%				50.00%
Other partner ownership percentage		50.00%				50.00%
Preferred interests \| Timberland Venture
Related Party Transaction [Line Items]
Ownership percentage				100.00%
Common interests \| Timberland Venture
Related Party Transaction [Line Items]
Other partner ownership percentage				91.00%
Ownership percentage				9.00%
Monetization SPEs
Related Party Transaction [Line Items]
SPE long-term notes		$ 511				$ 511	$ 511
Weighted average interest rate on SPE long-term notes \| Rate						5.60%	5.60%
Monetization SPEs \| Long-term notes due 2018
Related Party Transaction [Line Items]
SPE long-term notes		209				$ 209
Debt, Maturity Date						Dec. 31, 2018
Monetization SPEs \| Long-term notes due 2019
Related Party Transaction [Line Items]
SPE long-term notes		302				$ 302
Investment Maturity Date						Dec. 31, 2019
Buyer-sponsored SPEs
Related Party Transaction [Line Items]
SPE restricted financial investments		615				$ 615	$ 615
Weighted average interest rate on SPE financial investments \| Rate						5.50%	5.50%
Buyer-sponsored SPEs \| SPE restricted investment due in 2019
Related Party Transaction [Line Items]
SPE restricted financial investments		253				$ 253
Debt, Maturity Date						Dec. 31, 2019
Buyer-sponsored SPEs \| SPE restricted investment due in 2020
Related Party Transaction [Line Items]
SPE restricted financial investments		362				$ 362
Investment Maturity Date						Dec. 31, 2020
SPEs
Related Party Transaction [Line Items]
Interest expense						$ 29	$ 29	29
Interest income						34	34	$ 34
Net equity in SPEs		105				105
Net deferred tax liability		$ 116				$ 116
Twin Creeks Venture
Related Party Transaction [Line Items]
Proceeds from contribution of timberlands to related party (Note 8)							$ 440