Long-Term Debt Payable to Westlake (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2025	Dec. 31, 2024
Related Party Transaction [Line Items]
Weighted average interest rate	6.20%	6.40%
Limited Partner \| Senior Unsecured Revolving Credit Facility
Related Party Transaction [Line Items]
Long-term debt payable to Westlake	$ 399,674	$ 399,674
Limited Partner \| Senior Unsecured Revolving Credit Facility \| Long-term debt payable to Westlake
Related Party Transaction [Line Items]
Long-term debt payable to Westlake	$ 22,619	22,619
Credit spread adjustment	0.10%
Basis spread on variable rate, percent	1.75%
Limited Partner \| Senior Unsecured Revolving Credit Facility \| MLP Revolver
Related Party Transaction [Line Items]
Long-term debt payable to Westlake	$ 377,055	$ 377,055
Credit spread adjustment	0.10%
Limited Partner \| Senior Unsecured Revolving Credit Facility \| MLP Revolver \| Minimum
Related Party Transaction [Line Items]
Basis spread on variable rate, percent	1.75%
Limited Partner \| Senior Unsecured Revolving Credit Facility \| MLP Revolver \| Maximum
Related Party Transaction [Line Items]
Basis spread on variable rate, percent	2.75%

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

No definition available.

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- Definition

Weighted average interest rate of long-term debt outstanding calculated at point in time.

+ References

No definition available.

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- Definition

Amount of long-term debt classified as other, payable after one year or the operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
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-Name Accounting Standards Codification
-Section S99
-Paragraph 1
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479170/946-210-S99-1

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481990/310-10-45-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
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-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07(2)(c)(2)(i))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479134/946-220-S99-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
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-Name Accounting Standards Codification
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-Publisher FASB
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
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-Name Accounting Standards Codification
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- Definition

Debt Instrument, Credit Spread Adjustment

+ References

No definition available.

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