v3.25.2

Description of Business and Basis of Presentation (Details) $ in Thousands	Mar. 29, 2019 USD ($) shares	Aug. 04, 2014 shares	Jun. 30, 2025 numberOfCommonCarrierPipelines production_facility
Westlake Chemical OpCo LP
Limited Partners' Capital Account [Line Items]
Number of production facilities \| production_facility			3
Number of common carrier pipelines \| numberOfCommonCarrierPipelines			1
Westlake Chemical OpCo LP \| Affiliated Entity
Limited Partners' Capital Account [Line Items]
Limited partner interest	22.80%	10.60%
Limited partner interest, additional ownership	4.50%
Amount paid to purchase additional limited partner interest \| $	$ 201,445
Westlake Chemical OpCo LP \| Majority-Owned Subsidiary, Unconsolidated \| Westlake
Limited Partners' Capital Account [Line Items]
Limited partner interest	77.20%
Westlake Chemical OpCo GP LLC \| Limited Liability Company
Limited Partners' Capital Account [Line Items]
Limited partner interest		100.00%
Limited Partner
Limited Partners' Capital Account [Line Items]
Number of units sold in public offering (in shares) \| shares	2,940,818	12,937,500

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 272
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482987/272-10-50-3

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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.

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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
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 5
-Subparagraph (SAB Topic 4.F)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480008/505-10-S99-5

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480008/505-10-S99-1

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- Definition

Cash outflow related to the acquisition or continued holding of limited partnership interests held for investment purposes.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 13
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-13

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- Definition

Limited Liability Company (LLC) or Limited Partnership (LP), Members or Limited Partners, Additional Ownership Interest

+ References

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- Definition

Number of Common Carrier Pipelines

+ References

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- Definition

Number of Production Facilities

+ References

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Westlake Chemical Partners LP 10-Q