The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

+ Details

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- 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.

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- Definition

Net number of share options (or share units) granted during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

Number of share instruments newly issued under a share-based compensation plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

Share Based Compensation Arrangement by Share Based Payment Award, Outstanding Award as Percentage of Shares Issued

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Target level vesting rate

+ References

No definition available.

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Namespace Prefix:	wy_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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SHARE-BASED COMPENSATION Additional Information (Details) - USD ($)	9 Months Ended
	Sep. 30, 2017	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued during period	4,500,000.00
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average fair value of units granted	$ 32.79
Granted	763,000
Performance share units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average fair value of units granted	$ 37.93
Granted	348,000
Performance share units \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Final number of shares awarded of each grant's target	0.00%
Performance share units \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Final number of shares awarded of each grant's target	150.00%
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options granted	0
Stock appreciation rights
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted	0
Value management awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Target level vesting rate		$ 100