NET EARNINGS PER SHARE - Pro Forma Results Giving Effect to Common Stock Distribution for Diluted Earnings Per Common Share (Detail) (USD $) In Millions, except Share data in Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010	Sep. 30, 2010	Jun. 30, 2010	Mar. 31, 2010	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Net earnings (loss) attributable to Weyerhaeuser common shareholders	$ 65	$ 157	$ 10	$ 99	$ 171	$ 1,116	$ 14	$ (20)	$ 331	$ 1,281	$ (545)
Diluted earnings (loss) per share:
Net earnings per share, diluted	$ 0.12	$ 0.29	$ 0.02	$ 0.18	$ 0.32	$ 3.50	$ 0.07	$ (0.10)	$ 0.61	$ 3.99	$ (2.58)
Pro forma										$ 2.39	$ (1.02)
Diluted weighted average shares outstanding (in thousands):
As reported									539,879	321,096	211,342
Pro forma										537,013	535,661