BUSINESS SEGMENTS Reconciliation from Segment Totals to Consolidated (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	$ 1,693	$ 1,405
Intersegment sales	202	244
Third party and intersegment revenue, net	1,895	1,649
Net contribution to earnings	280	167
Interest expense, net of capitalized interest	(99)	(95)
Earnings from continuing operations before income taxes	181	72
Income taxes	(24)	(11)
Earnings from continuing operations	157	61
Earnings from discontinued operations, net of income taxes	0	20
Net earnings	157	81
Dividends on preference shares	0	(11)
Net earnings attributable to Weyerhaeuser common shareholders	157	70
Intersegment eliminations
Segment Reporting, Revenue Reconciling Item [Line Items]
Intersegment sales	(202)	(244)
Operating segments
Segment Reporting, Revenue Reconciling Item [Line Items]
Net contribution to earnings	346	231
Unallocated items
Segment Reporting, Revenue Reconciling Item [Line Items]
Net contribution to earnings	(66)	(64)
Timberlands
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	486	387
Intersegment sales	202	222
Net contribution to earnings	148	129
RE & ENR
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	53	39
Net contribution to earnings	26	15
Wood Products
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	1,154	979
Intersegment sales	0	22
Net contribution to earnings	$ 172	$ 87

Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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