BUSINESS SEGMENTS - Reconciliation from Segment Totals to Consolidated (Detail) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	$ 1,807	$ 1,964	$ 3,528	$ 3,700
Net contribution to earnings	245	440	448	773
Interest expense, net of capitalized interest (continuing and discontinued operations)	(88)	(85)	(171)	(168)
Income before income taxes (continuing and discontinued operations)	157	355	277	605
Income taxes (continuing and discontinued operations)	(13)	(64)	(32)	(120)
Net earnings	144	291	245	485
Dividends on preference shares	(11)	(11)	(22)	(22)
Net earnings attributable to Weyerhaeuser common shareholders	133	280	223	463
Continuing operations
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	1,807	1,964	3,528	3,700
Discontinued operations
Segment Reporting, Revenue Reconciling Item [Line Items]
Net contribution to earnings	0	29	0	45
Operating segments \| Continuing operations
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	2,016	2,171	3,984	4,164
Net contribution to earnings	225	363	482	645
Operating segments \| Timberlands \| Continuing operations
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	336	397	687	774
Net contribution to earnings	127	170	289	334
Operating segments \| Wood Products \| Continuing operations
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	1,004	1,077	1,927	1,975
Net contribution to earnings	71	102	133	166
Operating segments \| Cellulose Fibers \| Continuing operations
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	467	490	914	951
Net contribution to earnings	27	91	60	145
Operating intersegments \| Continuing operations
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	209	207	456	464
Operating intersegments \| Timberlands \| Continuing operations
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	187	186	415	424
Operating intersegments \| Wood Products \| Continuing operations
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	22	21	41	40
Intersegment eliminations \| Continuing operations
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	(209)	(207)	(456)	(464)
Unallocated Items \| Continuing operations
Segment Reporting, Revenue Reconciling Item [Line Items]
Net contribution to earnings	$ 20	$ 48	$ (34)	$ 83

Amount of current tax expense (benefit) and deferred tax expense (benefit) from income (loss) from continuing operations, income (loss) from discontinued operations, and gain (loss) from extraordinary items.

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