Related Party Transactions (Tables)

12 Months Ended

Dec. 31, 2019

Related Party Transactions [Abstract]

Schedule of Related Party Transactions

Charges from related parties in cost of sales were as follows:

	Year Ended December 31,
	2019		2018		2017
Feedstock purchased from Westlake and included in cost of sales	$	366,031	$	556,362	$	425,255
Other charges from Westlake and included in cost of sales	106,564		114,364		96,813
Total	$	472,595	$	670,726	$	522,068

Charges from related parties included within selling, general and administrative expenses were as follows:

	Year Ended December 31,
	2019		2018		2017
Services received from Westlake and included in selling, general and    administrative expenses	$	26,946	$	24,618	$	27,262

Sales to related parties were as follows:

	Year Ended December 31,
	2019		2018		2017
Net sales—Westlake	$	937,625	$	1,074,957	$	973,081

Debt payable to related parties was as follows:

	December 31,
	2019		2018
Long-term debt payable to Westlake	$	399,674	$	477,608

The Partnership's receivable under the Investment Management Agreement was as follows:

	December 31,
	2019		2018
Receivable under the Investment Management Agreement	$	162,773	$	148,956

	December 31,
	2019		2018
Accounts payable—Westlake	$	15,201	$	27,477

Charges from related parties for goods and services capitalized as assets were as follows:

	Year Ended December 31,
	2019		2018		2017
Goods and services purchased from Westlake and capitalized as assets	$	2,503	$	2,519	$	3,491

The Partnership's accounts receivable from Westlake were as follows:

	December 31,
	2019		2018
Accounts receivable—Westlake	$	42,847	$	57,280