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Related Party Transactions (Services from Related Parties Included in SG&A Expenses) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Related Party Transaction [Line Items]
Services received from Westlake and included in selling, general and administrative expenses	$ 28,271	$ 28,495	$ 29,751
Affiliated Entity | Westlake
Related Party Transaction [Line Items]
Services received from Westlake and included in selling, general and administrative expenses	$ 25,017	$ 25,654	$ 27,085

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