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))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Name Accounting Standards Codification
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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Data Type:	xbrli:monetaryItemType
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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-Topic 825
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13476-108611

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Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

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Balance Type:	na
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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.

+ References

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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.

+ Details

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Period Type:	instant

- 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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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- 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
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
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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

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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.

+ References

No definition available.

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Balance Type:	credit
Period Type:	instant

- 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
Namespace Prefix:	wy_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

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LONG-TERM DEBT AND LINES OF CREDIT (Detail) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Feb. 19, 2016
Repayments of Long-term Debt	$ 723	$ 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			893
Note Payable to Timberland Venture [Member]
Principal due to Timberland Venture	$ 783
Annual interest rate on note payable	7.375%
Note Payable to Timberland Venture [Member] \| Plum Creek [Member]
Note payable to Timberland Venture (Note 10)			$ 838
Term Loan due August 2017 [Member]
Term Loan, Maximum Borrowing Capacity	$ 600
Interest Rate Terms	LIBOR plus 1.05 percent
Term Loan, Outstanding	$ 600
Term Loan due September 2017 [Member]
Term Loan, Maximum Borrowing Capacity	$ 1,900
Interest Rate Terms	LIBOR plus 1.05 percent
Term Loan, Outstanding	$ 800