SELECTED QUARTERLY FINANCIAL INFORMATION (unaudited) - Key Quarterly Financial Data for the Last Two Years (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended									12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Net sales	$ 1,734	$ 1,820	$ 1,807	$ 1,721	$ 1,788	$ 1,915	$ 1,964	$ 1,736		$ 7,082	$ 7,403	$ 7,254
Operating income	217	259	243	200	294	318	400	308		919	1,320	634
Earnings from continuing operations before income taxes	51	175	157	120	214	237	328	234		503	1,013	320
Net earnings	70	191	144	101	177	1,164	291	194		506	1,826	563
Net earnings attributable to Weyerhaeuser common shareholders	$ 59	$ 180	$ 133	$ 90	$ 166	$ 1,153	$ 280	$ 183		$ 462	$ 1,782	$ 540
Basic net earnings per share attributable to Weyerhaeuser common shareholders	$ 0.11	$ 0.35	$ 0.26	$ 0.17	$ 0.32	$ 2.17	$ 0.48	$ 0.31		$ 0.89	$ 3.20	$ 0.95
Diluted net earnings per share attributable to Weyerhaeuser common shareholders	0.11	0.35	0.26	0.17	0.31	2.15	0.47	0.31		0.89	3.18	0.95
Dividends paid per share	0.31	0.31	0.29	0.29	0.29	$ 0.29	0.22	0.22		1.20	$ 1.02	$ 0.81
Gain on WRECO divestiture						$ 972					$ 972	$ 0
Maximum
Market prices - high/low	32.72	32.34	33.19	37.04	36.88	$ 34.60	33.26	31.59		37.04	$ 36.88
Minimum
Market prices - high/low	$ 26.73	$ 26.76	$ 31.06	$ 32.74	$ 31.61	$ 31.09	$ 27.48	$ 28.63		$ 26.73	$ 27.48
Unallocated Items | Coyote Springs Property | Fair Value, Inputs, Level 2 and 3
Non-cash impairment charge									$ 356