BUSINESS SEGMENTS - Reconciliation of Contribution to Earnings to Net Earnings Attributable to Weyerhaeuser (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Reconciliation of Contribution (Charge) to Earnings From Segment to Net Earnings [Line Items]
Net contribution to earnings	$ 2,374wy_NetContributionToEarnings	$ 805wy_NetContributionToEarnings	$ 788wy_NetContributionToEarnings
Interest expense, net of capitalized interest (continuing and discontinued operations)	347	371	348
Income before income taxes (continuing and discontinued operations)	2,027	434	440
Income taxes (continuing and discontinued operations)	(201)	129	(55)
Net earnings attributable to Weyerhaeuser	1,826us-gaap_NetIncomeLoss	563us-gaap_NetIncomeLoss	385us-gaap_NetIncomeLoss
Continuing operations
Reconciliation of Contribution (Charge) to Earnings From Segment to Net Earnings [Line Items]
Net contribution to earnings	1,357	689	667
Discontinued operations
Reconciliation of Contribution (Charge) to Earnings From Segment to Net Earnings [Line Items]
Net contribution to earnings	$ 1,017	$ 116	$ 121

The sum of current income tax expense or benefit and deferred income tax expense or benefit pertaining to continuing operations, tax effect allocated to a disposal group that is classified as a component of the entity reported as a separate component of income before extraordinary items, and tax effect of gains and losses from events or transactions meeting the criteria to be classified as an extraordinary item.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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This element represents the income or loss from both continuing operations and discontinued operations to the economic entity, after income or loss from equity method investments, but before income taxes, extraordinary items.

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Amount of the cost of borrowed funds accounted for as interest expense, including continuing and discontinued operations.

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This element represents the income or (loss) from continuing operations (before interest expense) attributable to the economic entity which may also be defined as revenue less expenses from ongoing operations, after income or loss from equity method investments, but before, interest expense, income taxes, extraordinary items, and noncontrolling interest.

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