BUSINESS SEGMENTS - Additional Financial Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Segment Reporting, Other Significant Reconciling Item [Line Items]
Depreciation, depletion and amortization	$ 472	$ 510	$ 486
Capital expenditures	281	384	427
Operating segments | Timberlands
Segment Reporting, Other Significant Reconciling Item [Line Items]
Depreciation, depletion and amortization	257	301	319
Capital expenditures	104	112	117
Operating segments | Real Estate & ENR
Segment Reporting, Other Significant Reconciling Item [Line Items]
Depreciation, depletion and amortization	14	14	14
Capital expenditures	0	0	0
Operating segments | Wood Products
Segment Reporting, Other Significant Reconciling Item [Line Items]
Depreciation, depletion and amortization	195	191	149
Capital expenditures	176	257	306
Unallocated Items
Segment Reporting, Other Significant Reconciling Item [Line Items]
Depreciation, depletion and amortization	6	4	4
Capital expenditures	$ 1	$ 15	$ 4