Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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(22))
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Balance Type:	credit
Period Type:	instant

- Definition

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (a)
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-Section 50
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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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- Definition

Description of the interest rate as being fixed or variable, and, if variable, identification of the index or rate on which the interest rate is based and the number of points or percentage added to that index or rate to set the rate, and other pertinent information, such as frequency of rate resets.

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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

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- Definition

Identify the stated interest rate per the agreement, for example, leasing and debt arrangements between related parties.

+ References

No definition available.

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- Definition

The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 45
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-Name Accounting Standards Codification
-Glossary Financing Activities
-URI http://asc.fasb.org/extlink&oid=6513228

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- Definition

Principal due to Timberland Venture

+ References

No definition available.

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- Definition

Maximum borrowing capacity under the term loan without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the term loan.

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No definition available.

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Balance Type:	credit
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- Definition

The carrying value as of the balance sheet date of the outstanding long-term obligations drawn from a term loan, which is a bank's commitment to make loans up to a specific amount.

+ References

No definition available.

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Name:	wy_TermLoanOutstanding
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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LONG-TERM DEBT AND LINES OF CREDIT (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Feb. 19, 2016	Dec. 31, 2015
Repayments of Long-term Debt	$ 720	$ 0
Plum Creek [Member]
Repayments of Long-term Debt	720
Senior Note due 2021 [Member]
Long-term Debt	$ 569
Interest Rate, Stated Percentage	4.70%
Senior Note due 2021 [Member] \| Plum Creek [Member]
Long-term Debt, Fair Value			$ 614
Senior Note due 2023 [Member]
Long-term Debt	$ 325
Interest Rate, Stated Percentage	3.25%
Senior Note due 2023 [Member] \| Plum Creek [Member]
Long-term Debt, Fair Value			324
Installment Note Payable [Member]
Long-term Debt	$ 860
Interest Rate, Stated Percentage	5.207%
Installment Note Payable [Member] \| Plum Creek [Member]
Long-term Debt, Fair Value			892
Note Payable to Timberland Venture [Member]
Principal due to Timberland Venture	$ 783
Note payable to Timberland Venture (Note 10)			$ 837
Annual interest rate on note payable	7.375%
Term Loan due August 2017 [Member]
Term Loan, Maximum Borrowing Capacity	$ 600
Interest Rate Terms	LIBOR plus 1.05%
Term Loan, Outstanding	$ 600
Term Loan due September 2017 [Member]
Term Loan, Maximum Borrowing Capacity	$ 1,900
Interest Rate Terms	LIBOR plus 1.05%
Term Loan, Outstanding	$ 500
Fair Value, Inputs, Level 2 [Member] \| Note Payable to Timberland Venture [Member]
Note payable to Timberland Venture (Note 10)	$ 843			$ 0