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Related Party Transactions (Related Party Leases) (Details)	12 Months Ended
	Dec. 31, 2025 USD ($)	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	Aug. 04, 2014
Westlake | Affiliated Entity
Related Party Transaction [Line Items]
Operating lease expense	$ 1,705,000	$ 1,843,000	$ 1,869,000
Westlake Chemical OpCo LP | Westlake | Investee | Site Lease Agreement
Related Party Transaction [Line Items]
Site lease agreement, number	2
Term of operating lease				50 years
Site lease expense	$ 1

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- Definition

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

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