BUSINESS SEGMENTS - Reconciliation from Segment Totals to Consolidated (Detail) - USD ($) $ in Millions	3 Months Ended
Jun. 30, 2016	Mar. 31, 2016	Mar. 31, 2015
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales		$ 1,835	$ 1,727
Net contribution to earnings		198	203
Interest expense, net of capitalized interest		(97)	(83)
Earnings before income taxes		101	120
Income taxes		(20)	(19)
Net earnings		81	101
Dividends on preference shares		(11)	(11)
Net earnings attributable to Weyerhaeuser common shareholders		70	90
Continuing operations
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales		1,835	1,727
Operating segments \| Continuing operations
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales		2,079	1,974
Net contribution to earnings		259	257
Operating segments \| Timberlands \| Continuing operations
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales		387	323
Net contribution to earnings		129	139
Operating segments \| RE & ENR \| Continuing operations
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales		39	34
Net contribution to earnings		15	23
Operating segments \| Wood Products \| Continuing operations
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales		979	923
Net contribution to earnings		87	62
Operating segments \| Cellulose Fibers \| Continuing operations
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales		430	447
Net contribution to earnings		28	33
Operating intersegments \| Continuing operations
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales		244	247
Operating intersegments \| Timberlands \| Continuing operations
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales		222	228
Operating intersegments \| Wood Products \| Continuing operations
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales		22	19
Intersegment eliminations \| Continuing operations
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales		(244)	(247)
Unallocated Items \| Continuing operations
Segment Reporting, Revenue Reconciling Item [Line Items]
Net contribution to earnings		$ (61)	$ (54)
Subsequent Event \| Cellulose Fibers
Segment Reporting, Revenue Reconciling Item [Line Items]
Proceeds from Sale of Property Held-for-sale	$ 2,200

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

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