The number of units or percentage investment held by one or more members or limited partners of the LLC or LP.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 272

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70478-108055

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- Definition

The number of units sold in a public offering of each class of partners' capital account. Units represent shares of ownership of the general, limited, and preferred partners.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 5

-Subparagraph (SAB TOPIC 4.F)

-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187171-122770

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 16

-Subparagraph a, b

-Article 6

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- Definition

The cash inflow from the issuance of common limited partners units during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 14

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3255-108585

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Gross Proceeds From Issuance Of Common Limited Partners Units

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- Definition

Net Proceeds Distributed To Parent Company From Initial Public Offering

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- Definition

Other Ownership Interests, Percentage of Ownership After Transaction

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- Definition

The cash outflow for cost incurred directly with the issuance of an equity security.

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- Definition

Per unit amount received by subsidiary or equity investee for each unit issued or sold in the unit transaction.

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No definition available.

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- Definition

Subsidiary Initial Public Offering, Use Of Proceeds

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Westlake Chemical Partners LP (Details) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended			0 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Aug. 04, 2014
Related Party Transaction [Line Items]
Approximate proceeds from sale of units	$ 286,088	$ 0	$ 0
Westlake Chemical Partners LP [Member] \| IPO [Member] \| Limited Partner [Member]
Related Party Transaction [Line Items]
Limited partner interest				52.20%
Westlake Chemical Partners LP [Member] \| IPO [Member] \| Subsidiaries [Member]
Related Party Transaction [Line Items]
Percentage sold to public in IPO				47.80%
Westlake Chemical OpCo LP [Member] \| IPO [Member] \| Limited Partner [Member]
Related Party Transaction [Line Items]
Limited partner interest				89.40%
Westlake Chemical Partners LP [Member] \| IPO [Member] \| Subsidiaries [Member]
Related Party Transaction [Line Items]
Net proceeds distributed to the Company from the initial public offering				230,669
Westlake Chemical Partners LP [Member] \| IPO [Member] \| Subsidiaries [Member] \| Limited Partner [Member]
Related Party Transaction [Line Items]
Number of units sold in public offering				12,937,500
Price per unit				24
Approximate proceeds from sale of units				286,088
Estimated offering expenses from sale of partnership units				(24,412)
Limited partner interest				10.60%
Total proceeds from the initial public offering				310,500
Westlake Chemical Partners LP [Member] \| Over-Allotment Option [Member] \| Subsidiaries [Member] \| Limited Partner [Member]
Related Party Transaction [Line Items]
Number of units sold in public offering				1,687,500
Subsidiary of Common Parent [Member] \| Westlake Chemical OpCo LP [Member] \| IPO [Member] \| Subsidiaries [Member] \| Limited Partner [Member]
Related Party Transaction [Line Items]
Limited partner interest				10.60%
Cash Reserve Turnaround [Member] \| Westlake Chemical OpCo LP [Member] \| IPO [Member] \| Subsidiaries [Member]
Related Party Transaction [Line Items]
Amount used from proceeds				(55,419)
Preformation Capital Expenditure [Member] \| Westlake Chemical OpCo LP [Member] \| IPO [Member] \| Subsidiaries [Member]
Related Party Transaction [Line Items]
Amount used from proceeds				(151,729)
Intercompany Debt [Member] \| Westlake Chemical OpCo LP [Member] \| IPO [Member] \| Subsidiaries [Member]
Related Party Transaction [Line Items]
Amount used from proceeds				(78,940)