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, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Net earnings attributable to Weyerhaeuser common shareholders	$ 143	$ 117	$ 84	$ 41	$ 65	$ 157	$ 10	$ 99	$ 385	$ 331	$ 1,281
Diluted earnings per share:
As reported	$ 0.26	$ 0.22	$ 0.16	$ 0.08	$ 0.12	$ 0.29	$ 0.02	$ 0.18	$ 0.71	$ 0.61	$ 3.99
Pro forma											$ 2.39
Diluted weighted average shares outstanding (in thousands):
As reported									542,310	539,879	321,096
Pro forma											537,013