BUSINESS SEGMENTS Reconciliation from Segment Totals to Consolidated (Detail) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	$ 1,709	$ 1,355	$ 4,769	$ 3,980
Net contribution to earnings	298	175	740	543
Interest expense, net of capitalized interest	(114)	(87)	(323)	(254)
Earnings from continuing operations before income taxes	184	88	417	289
Income taxes	(22)	44	(64)	36
Earnings from continuing operations	162	132	353	325
Earnings from discontinued operations, net of income taxes	65	59	123	111
Net earnings	227	191	476	436
Dividends on preference shares (Note 5)	0	(11)	(22)	(33)
Net earnings attributable to Weyerhaeuser common shareholders	227	180	454	403
Continuing operations
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	1,709	1,355	4,769	3,980
Operating segments \| Continuing operations
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	1,942	1,585	5,461	4,666
Net contribution to earnings	307	211	831	633
Operating segments \| Timberlands \| Continuing operations
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	484	310	1,342	961
Net contribution to earnings	122	107	376	363
Operating segments \| RE & ENR \| Continuing operations
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	48	22	125	69
Net contribution to earnings	15	19	42	52
Operating segments \| Wood Products \| Continuing operations
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	1,177	1,023	3,302	2,950
Net contribution to earnings	170	85	413	218
Operating Intersegments [Member] \| Continuing operations
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	233	230	692	686
Operating Intersegments [Member] \| Timberlands \| Continuing operations
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	216	210	631	625
Operating Intersegments [Member] \| Wood Products \| Continuing operations
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	17	20	61	61
Intersegment eliminations \| Continuing operations
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	(233)	(230)	(692)	(686)
Unallocated items \| Continuing operations
Segment Reporting, Revenue Reconciling Item [Line Items]
Net contribution to earnings	$ (9)	$ (36)	$ (91)	$ (90)

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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