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RELATED PARTIES - Additional Information (Details) $ in Millions		3 Months Ended		12 Months Ended
	Apr. 01, 2016 USD ($) a	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($) a	Dec. 31, 2020	Dec. 31, 2018 USD ($) Rate	Dec. 31, 2017 USD ($) a	Dec. 31, 2016 USD ($)
Related Party Transaction [Line Items]
Gain on sale of timberlands					$ 0	$ (99)	$ 0
Proceeds from sale of Southern timberlands					0	203	0
Proceeds from contribution of timberlands to related party (Note 9)					0	0	440
Proceeds from redemption of ownership interest in related party					0	108	0
Interest expense					375	393	431
Real Estate Development Ventures
Related Party Transaction [Line Items]
Expiration of joint venture agreement				2020
Equity Method Investments			$ 31			$ 31
Proceeds from Equity Method Investment, Distribution, Return of Capital					$ 1
Twin Creeks Venture
Related Party Transaction [Line Items]
Sale of Timberland acreage \| a			100,000			100,000
Gain on sale of timberlands			$ (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 9)	$ 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%
Class B Properties \| Real Estate Development Ventures
Related Party Transaction [Line Items]
Equity method investment, ownership percentage		50.00%			50.00%
Monetization SPEs
Related Party Transaction [Line Items]
Weighted average interest rate on SPE long-term notes \| Rate					5.60%
Monetization SPEs \| Long-Term Debt due 2018 [Member]
Related Party Transaction [Line Items]
Payments related to liabilities from our monetized SPEs		$ 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
Debt, Maturity Date					Sep. 30, 2019
Buyer-sponsored SPEs
Related Party Transaction [Line Items]
Weighted average interest rate on SPE financial investments \| Rate					5.50%
Buyer-sponsored SPEs \| SPE restricted investment due in 2019
Related Party Transaction [Line Items]
SPE restricted financial investments		253			$ 253
Investment Maturity Date					Mar. 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					Mar. 31, 2020
SPEs
Related Party Transaction [Line Items]
Interest expense					$ 29	$ 29	29
Interest income					$ 34	$ 34	$ 34