Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2018	Apr. 23, 2018
Document Information [Line Items]
Entity Registrant Name	WEYERHAEUSER CO
Trading Symbol	WY
Entity Central Index Key	0000106535
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Document Type	10-Q
Document Period End Date	Mar. 31, 2018
Document Fiscal Year Focus	2018
Document Fiscal Period Focus	Q1
Amendment Flag	false
Entity Common Stock, Shares Outstanding		757,013,955