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Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478964/842-20-50-3

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- References

No definition available.

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Period covered by the long-term purchase commitment, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

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IMA, Partnership earned amount added to market rate, basis points

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Lessee Leasing Arrangement, Operating Leases, Number

No definition available.

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Long-term Purchase Commitment, Compliance Surcharge

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Long-term Purchase Commitment, Curtail Option Percentage

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Long-term Purchase Commitment, Excess Production Percentage

No definition available.

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Long-term Purchase Commitment, Exchange Fee, Fixed Margin

No definition available.

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Long-term Purchase Commitment, Maximum Volume Required

No definition available.

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Long-term Purchase Commitment, Minimum Percentage Required

No definition available.

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Long-term Purchase Commitment, Renewal Term

No definition available.

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Long-term Purchase Commitment, Terms of Fee, Number Of Years Used To Calculate Average Expenses

No definition available.

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Purchase Commitment, Purchase Agreement, Mass

No definition available.

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Receivables under Investment Management Agreements with Related Parties, Current

No definition available.

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Related Party Transaction, Counterparty Default, Period Of Default, Allowing Termination Of Agreement

No definition available.

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Related Party Transaction, Term Of Agreement

No definition available.

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Term of Investment Management Agreement with Related Party, Maximum

No definition available.

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Name:	us-gaap_RelatedPartyTransactionAxis=wlkp_ExchangeAgreementMember
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Name:	dei_LegalEntityAxis=wlkp_ParentCompanyAndSubsidiariesExcludingReportingEntityAndSubsidiariesMember
Namespace Prefix:
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Period Type:

Name:	us-gaap_RelatedPartyTransactionAxis=wlkp_EthyleneSalesAgreementMember
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Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=us-gaap_InvesteeMember
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Data Type:	na
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Namespace Prefix:
Data Type:	na
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Name:	us-gaap_RelatedPartyTransactionAxis=wlkp_FeedstockSupplyAgreementMember
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