Face (par) amount of debt instrument at time of issuance.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

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(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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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.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

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(a)(2))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Balance Type:	na
Period Type:	duration

- Definition

Minimum Debt Amount Guaranteed By Subsidiaries

+ References

No definition available.

+ Details

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Namespace Prefix:	wlk_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Percentage of the principal required in the event bonds are redeemed

+ References

No definition available.

+ Details

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Namespace Prefix:	wlk_
Data Type:	num:percentItemType
Balance Type:	na
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- Details

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Long-Term Debt (GO Zone Act Senior Notes Due 2032) (Details) - USD ($) $ in Thousands	1 Months Ended		12 Months Ended
	Jul. 31, 2010	Dec. 31, 2007	Dec. 31, 2015	Dec. 31, 2014	Jul. 02, 2010	Dec. 13, 2007
Debt Instrument [Line Items]
Stated interest rate			6.50%
Minimum debt amount guaranteed by subsidiaries			$ 5,000
GO Zone 6 3/4% Senior Notes Due 2032 [Member]
Debt Instrument [Line Items]
Stated interest rate			6.75%	6.75%
Redeemed Prior To November 1, 2017 [Member] \| GO Zone 6 3/4% Senior Notes Due 2032 [Member]
Debt Instrument [Line Items]
Percentage of principal required if called			100.00%
Redeemed On Or After November 1, 2017 [Member] \| GO Zone 6 3/4% Senior Notes Due 2032 [Member]
Debt Instrument [Line Items]
Percentage of principal required if called			100.00%
Gulf Opportunity Zone Act Of 2005 [Member]
Debt Instrument [Line Items]
Senior notes, principal amount issued					$ 100,000
Maturity date	Aug. 01, 2029
Gulf Opportunity Zone Act Of 2005 [Member] \| GO Zone 6 3/4% Senior Notes Due 2032 [Member]
Debt Instrument [Line Items]
Senior notes, principal amount issued						$ 250,000
Stated interest rate						6.75%
Maturity date		Nov. 01, 2032