Percentage investment held by the managing member or general partner of the limited liability company (LLC) or limited partnership (LP).

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-SubTopic 10
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-URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70478-108055

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- Definition

Percentage investment held by members or limited partners of limited liability company (LLC) or limited partnership (LP).

+ References

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- Definition

The number of each class of partnership units outstanding at the balance sheet date. Units represent shares of ownership of the general, limited, and preferred partners.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-04.16(a))
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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
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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.

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No definition available.

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- Definition

Partners' Units, Maximum Aggregate Offering Amount, ATM

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Westlake Chemical Partners LP (Details) - USD ($) $ in Millions		6 Months Ended	9 Months Ended
	Oct. 04, 2018	Jun. 30, 2021	Sep. 30, 2015
Related Party Transaction [Line Items]
Partners' Capital Account, Units, Sold in Public Offering			12,937,500
Partners' Units, Maximum Aggregate Offering Amount, ATM	$ 50
Westlake Chemical OpCo LP [Member] \| Subsidiary of Common Parent [Member] \| Limited Partner [Member]
Related Party Transaction [Line Items]
Limited Liability Company (LLC) or Limited Partnership (LP), Managing Member or General Partner, Ownership Interest		22.80%
Limited Liability Company or Limited Partnership, Members or Limited Partners, Ownership Interest		77.20%
Westlake Chemical Partners LP [Member] \| Subsidiary of Common Parent [Member] \| Limited Partner [Member]
Related Party Transaction [Line Items]
Limited Liability Company or Limited Partnership, Members or Limited Partners, Ownership Interest		40.10%
Ownership interest (in units)		14,122,230