Related Party Transactions (Accounts Receivable from and Accounts Payable to Related Parties) (Details) - USD ($) $ in Thousands |
3 Months Ended | 9 Months Ended | 12 Months Ended | ||
|---|---|---|---|---|---|
Sep. 30, 2026 |
Sep. 30, 2025 |
Sep. 30, 2026 |
Sep. 30, 2025 |
Dec. 31, 2025 |
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| 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") | $ 65,715 | $ 65,715 | $ 23,378 | ||
| Affiliated Entity | |||||
| Related Party Transaction [Line Items] | |||||
| Accounts receivable, net—Westlake | 43,630 | 43,630 | 63,571 | ||
| Accounts payable | 19,533 | 19,533 | 19,132 | ||
| Buyer deficiency fee | 5,835 | ||||
| Affiliated Entity | Westlake | |||||
| Related Party Transaction [Line Items] | |||||
| Accrued interest included in receivable under IMA | 544 | 544 | $ 206 | ||
| Interest earned related to the IMA | $ 544 | $ 224 | $ 1,218 | $ 2,333 | |
| X | ||||||||||
- Definition Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer). Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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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. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Accrued interest included in receivable under IMA No definition available.
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- Definition Buyer deficiency fee No definition available.
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- Definition IMA, Partnership earned amount added to market rate, basis points No definition available.
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- Definition Interest earned related to the IMA No definition available.
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- Definition Receivables under Investment Management Agreements with Related Parties, Current No definition available.
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- Details
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- Details
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