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RELATED PARTIES - Additional Information (Details) $ in Millions		3 Months Ended	6 Months Ended	12 Months Ended
	Apr. 01, 2016 USD ($) a	Sep. 30, 2016 USD ($)	Aug. 30, 2016	Dec. 31, 2020	Dec. 31, 2016 USD ($) Rate	Dec. 31, 2015 USD ($) Rate	Dec. 31, 2014 USD ($)
Related Party Transaction [Line Items]
Number of Qualifying Special Purpose Entities					3
Proceeds from contribution of timberlands to related party					$ 440	$ 0	$ 0
Interest expense					431	341	338
Real Estate Development Ventures
Related Party Transaction [Line Items]
Expiration of joint venture agreement				2020
Maximum exposure to loss					56
Timberland Venture
Related Party Transaction [Line Items]
Gain on redemption of debt instrument		$ 6
Twin Creeks Venture
Related Party Transaction [Line Items]
Term of timber lease	3 years
Contributed acres of timberlands to venture \| a	260,000
Agreed-upon value of acres contributed	$ 560
Proceeds from contribution of timberlands to related party					$ 440
Ownership interest					21.00%
Other partner ownership interest					79.00%
Expected total committed capital					$ 950
Expected capital contributions					$ 85
Term of related party venture					15 years
Guaranteed annual return					3.00%
Percentage of profit in excess of guaranteed annual return					75.00%
Catchlight Energy
Related Party Transaction [Line Items]
Equity affiliate, proceeds from dissolution							0
Class A Properties \| Real Estate Development Ventures
Related Party Transaction [Line Items]
Equity method investment, ownership percentage					3.00%
Other partner ownership percentage					97.00%
Class B Properties \| Real Estate Development Ventures
Related Party Transaction [Line Items]
Equity method investment, ownership percentage					50.00%
Other partner ownership percentage					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
Weighted average interest rate on SPE long-term notes \| Rate					5.60%	5.60%
Monetization SPEs \| Long-term notes due 2019
Related Party Transaction [Line Items]
SPE long-term notes					$ 209
Debt Instrument, Maturity Date					Dec. 31, 2019
Monetization SPEs \| Long-term notes due 2020
Related Party Transaction [Line Items]
SPE long-term notes					$ 302
Debt Instrument, Maturity Date					Dec. 31, 2020
Buyer-sponsored SPEs
Related Party Transaction [Line Items]
SPE restricted financial investments					$ 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
Investment Maturity Date					Dec. 31, 2019
Buyer-sponsored SPEs \| SPE restricted investment due in 2020
Related Party Transaction [Line Items]
SPE restricted financial investments					$ 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
Net deferred tax liability					$ 180