CONSOLIDATED STATEMENT OF COMPREHENSIVE INCOME (Parenthetical) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Statement Of Income And Comprehensive Income [Abstract]
Changes in unamortized actuarial loss, tax expense (benefit)	$ 9	$ 63	$ 120	$ 82
Changes in unamortized net prior service credit, tax expense (benefit)	$ 0	$ 1	$ 0	$ 1

Other Comprehensive Income Change In Net Actuarial Gain Loss Tax

No definition available.

Name:	wy_ChangesInUnamortizedNetPensionAndOtherPostretirementBenefitLossTaxExpenseBenefit
Namespace Prefix:	wy_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration