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Related Party Transactions (Receivable under the Investment Management Agreement) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Related Party Transaction [Line Items]
IMA, Partnership earned amount added to market rate, basis points	five
Receivable under the Investment Management Agreement—Westlake Corporation ("Westlake")	$ 23,378	$ 134,557
Westlake | Affiliated Entity
Related Party Transaction [Line Items]
Interest earned related to the IMA	2,539	5,364	$ 4,424
Westlake | Affiliated Entity | Accounts Receivable
Related Party Transaction [Line Items]
Accrued interest included in receivable under IMA	$ 206	$ 1,385

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- Definition

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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
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-Publisher FASB
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
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