BUSINESS SEGMENTS Reconciliation from Segment Totals to Consolidated (Detail) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	$ 1,655	$ 1,345	$ 3,060	$ 2,625
Net contribution to earnings	275	209	442	368
Interest expense, net of capitalized interest	(114)	(85)	(209)	(167)
Earnings from continuing operations before income taxes	161	124	233	201
Income taxes	(31)	1	(42)	(8)
Earnings from continuing operations	130	125	191	193
Earnings from discontinued operations, net of income taxes	38	19	58	52
Net earnings	168	144	249	245
Dividends on preference shares	(11)	(11)	(22)	(22)
Net earnings attributable to Weyerhaeuser common shareholders	157	133	227	223
Continuing operations
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	1,655	1,345	3,060	2,625
Operating segments \| Continuing operations
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	1,870	1,554	3,519	3,081
Net contribution to earnings	293	198	524	422
Operating segments \| Timberlands \| Continuing operations
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	471	328	858	651
Net contribution to earnings	125	117	254	256
Operating segments \| RE & ENR \| Continuing operations
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	38	13	77	47
Net contribution to earnings	12	10	27	33
Operating segments \| Wood Products \| Continuing operations
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	1,146	1,004	2,125	1,927
Net contribution to earnings	156	71	243	133
Operating Intersegments [Member] \| Continuing operations
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	215	209	459	456
Operating Intersegments [Member] \| Timberlands \| Continuing operations
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	193	187	415	415
Operating Intersegments [Member] \| Wood Products \| Continuing operations
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	22	22	44	41
Intersegment eliminations \| Continuing operations
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	(215)	(209)	(459)	(456)
Unallocated items \| Continuing operations
Segment Reporting, Revenue Reconciling Item [Line Items]
Net contribution to earnings	$ (18)	$ 11	$ (82)	$ (54)

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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