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TIMBERLAND ACQUISITIONS AND DIVESTITURES - Additional Information (Details) $ in Millions								3 Months Ended
	Nov. 19, 2020 USD ($)	Nov. 17, 2020 USD ($)	Sep. 01, 2020 a	Mar. 26, 2020 USD ($)	Dec. 17, 2019 a	Nov. 13, 2019 USD ($)	Sep. 16, 2019 a	Dec. 31, 2019 USD ($)	Dec. 31, 2020 USD ($)
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Impairment charges								$ 80
Assets held for sale								$ 140	$ 0
Oregon
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Area of timberlands agreed to be sold \| a			149,000
Area of timberlands agreed to be purchased \| a			85,000
Cash to be received from sale of timberlands		$ 381
Gain on sale of discontinued and other operations		$ 182
Proceeds from disposition of operations	$ 425
Business combination timber and timberlands at cost, less depletion	421
Business combination property and equipment	$ 4
Montana
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Area of timberlands agreed to be sold \| a					630,000
Proceeds from disposition of operations				$ 145
Michigan
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Gain on sale of discontinued and other operations						$ 48
Proceeds from disposition of operations						$ 297
Number of acers of timberlands agreed to be sold \| a							555,000