Total investments in (A) an entity in which the entity has significant influence, but does not have control, (B) subsidiaries that are not required to be consolidated and are accounted for using the equity and or cost method, and (C) an entity in which the reporting entity shares control of the entity with another party or group. Includes long-term advances receivable from a party that is affiliated with the reporting entity by means of direct or indirect ownership.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.12)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The cash inflow from the capital received in cash from a partner in a partnership during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3255-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Activities
-URI http://asc.fasb.org/extlink&oid=6513228

+ Details

Name:	us-gaap_ProceedsFromPartnershipContribution
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_ScheduleOfEquityMethodInvestmentsLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Agreed-Upon Value of Acres Contributed

+ References

No definition available.

+ Details

Name:	wy_AgreedUponValueofAcresContributed
Namespace Prefix:	wy_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Contributed Acres of Timberlands to Venture

+ References

No definition available.

+ Details

Name:	wy_ContributedAcresofTimberlandstoVenture
Namespace Prefix:	wy_
Data Type:	num:areaItemType
Balance Type:	na
Period Type:	instant

- Definition

Guaranteed Annual Return (minimum)

+ References

No definition available.

+ Details

Name:	wy_GuaranteedAnnualReturn
Namespace Prefix:	wy_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

This item represents the entity's proportionate share (from continuing operations) for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

+ References

No definition available.

+ Details

Name:	wy_IncomeLossFromEquityMethodInvestmentsfromContinuingOperations
Namespace Prefix:	wy_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The ownership interest (percentage) in the venture.

+ References

No definition available.

+ Details

Name:	wy_OwnershipInterest
Namespace Prefix:	wy_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of Profit in Excess of Guaranteed Annual Return

+ References

No definition available.

+ Details

Name:	wy_PercentageofProfitinExcessofGuaranteedAnnualReturn
Namespace Prefix:	wy_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=wy_RealEstateDevelopmentVenturesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=wy_TwinCreeksVentureMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

RELATED PARTIES Additional Information (Details)		3 Months Ended
RELATED PARTIES Additional Information (Details)	Apr. 01, 2016 USD ($) a	Mar. 31, 2017 USD ($)	Mar. 31, 2016 USD ($)	Dec. 31, 2016 USD ($)
Schedule of Equity Method Investments [Line Items]
Investments in and advances to joint ventures		$ 56,000,000		$ 56,000,000
Equity earnings from joint ventures		0	$ 5,000,000
Real Estate Development Ventures
Schedule of Equity Method Investments [Line Items]
Investments in and advances to joint ventures		56,000,000		$ 56,000,000
Equity earnings from joint ventures		$ 0
Twin Creeks Venture
Schedule of Equity Method Investments [Line Items]
Contributed acres of timberlands to venture \| a	260,000
Agreed-upon value of acres contributed	$ 560,000,000
Proceeds from contribution of timberlands to related party	$ 440,000,000
Ownership interest		21.00%
Guaranteed annual return		3.00%
Percentage of profit in excess of guaranteed annual return		75.00%