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DISCONTINUED OPERATIONS - Additional Information (Details) - USD ($) shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Jun. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Common stock in exchange for the distribution of shares of Weyerhaeuser Real Estate Company (WRECO) to our shareholders	59
Net cash proceeds			$ 0	$ 707
Net gain on divestiture	$ 972			$ 972
Real Estate Divestiture
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net cash proceeds	$ 707
Net proceeds from issuance of debt		$ 887
4.375% notes due 2019 \| Real Estate Divestiture
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Unsecured and unsubordinated senior debt obligations issued by WRECO		$ 450
Debt, interest rate		4.375%
Debt, maturity date		Jun. 15, 2019
5.875% notes due 2024 \| Real Estate Divestiture
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Unsecured and unsubordinated senior debt obligations issued by WRECO		$ 450
Debt, interest rate		5.875%
Debt, maturity date		Jun. 15, 2024