v3.26.3
Related Party Transactions (Tables)
 9 Months Ended
Sep. 30, 2026
Related Party Transactions [Abstract]  
Schedule of Related Party Transactions Sales to related parties were as follows:
Three Months Ended September 30,Nine Months Ended September 30,
2026202520262025
Net sales—Westlake$261,935 $276,539 $763,056 $736,396 
Charges from related parties included in cost of sales were as follows:
Three Months Ended September 30,Nine Months Ended September 30,
2026
2025 (1)
2026
2025 (1)
Feedstock purchased from Westlake and included in cost of sales$112,056 $104,753 $317,295 $298,146 
Other charges from Westlake and included in cost of sales45,288 43,973 140,349 132,407 
$157,344 $148,726 $457,644 $430,553 
_____________________________
(1)Revised. As previously disclosed, feedstock purchased from Westlake and included in cost of sales was $95,110 and $271,176, and other charges from Westlake and included in cost of sales were $33,952 and $99,158, for the three and nine months ended September 30, 2025, respectively. See Revision of Previously Reported Amounts below.
Charges from related parties included within selling, general and administrative expenses were as follows:
Three Months Ended September 30,Nine Months Ended September 30,
2026202520262025
Services received from Westlake and included in selling, general and administrative expenses$7,861 $6,691 $20,898 $18,398 
Charges from related parties for goods and services capitalized as assets were as follows:
Three Months Ended September 30,Nine Months Ended September 30,
2026202520262025
Goods and services purchased from Westlake and capitalized as assets$1,151 $462 $2,225 $6,943 
The Partnership's receivable under the Investment Management Agreement was as follows:
September 30,
2026		December 31,
2025
Receivable under the Investment Management Agreement$65,715 $23,378 
The Partnership's accounts receivable from Westlake were as follows:
September 30,
2026		December 31,
2025
Accounts receivable—Westlake$43,630 $63,571 
The Partnership's accounts payable to Westlake were as follows:
September 30,
2026		December 31,
2025
Accounts payable—Westlake$19,533 $19,132 
Debt payable to related parties was as follows:
September 30,
2026		December 31,
2025
Long-term debt payable to Westlake$399,674 $399,674 
Schedule of Error Corrections and Prior Period Adjustments
The following tables present the amounts by which the previously disclosed amounts for other periods were understated:
Year Ended December 31,
202520242023
Feedstock purchased from Westlake and included in cost of sales$37,586 $38,269 $39,207 
Other charges from Westlake and included in cost of sales43,275 32,887 38,363 
$80,861 $71,156 $77,570 
Three Months Ended March 31,Three Months Ended June 30,Six Months Ended June 30,
202620252026202520262025
Feedstock purchased from Westlake and included in cost of sales$11,350 $8,154 $10,233 $9,173 $21,583 $17,327 
Other charges from Westlake and included in cost of sales11,293 11,986 10,815 11,242 22,108 23,228 
$22,643 $20,140 $21,048 $20,415 $43,691 $40,555