Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Current assets
Cash and cash equivalents	$ 84,615	$ 19,744
Receivable under the Investment Management Agreement—Westlake Chemical Corporation (Westlake)	276,501	148,956
Accounts receivable, net—Westlake	47,626	57,280
Accounts receivable, net—third parties	15,495	16,404
Inventories	4,171	4,388
Prepaid expenses and other current assets	251	370
Total current assets	428,659	247,142
Property, plant and equipment, net	1,138,434	1,148,265
Goodwill	5,814	5,814
Deferred charges and other assets, net	58,366	60,904
Total assets	1,631,273	1,462,125
Current liabilities
Accounts payable—Westlake	19,344	27,477
Accounts payable—third parties	7,481	5,045
Accrued and other liabilities	20,433	16,250
Total current liabilities	47,258	48,772
Long-term debt payable to Westlake	601,119	477,608
Deferred income taxes	1,677	1,664
Operating lease liabilities	1,272	0
Total liabilities	651,326	528,044
Commitments and contingencies (Note 12)
EQUITY
Total Westlake Chemical Partners LP partners' capital	279,742	215,810
Noncontrolling interest in Westlake Chemical OpCo LP (OpCo)	700,205	718,271
Total equity	979,947	934,081
Total liabilities and equity	1,631,273	1,462,125
Limited Partner [Member] | Common units [Member] | Publicly and Privately Held [Member]
EQUITY
Limited Partners' Capital Account	473,119	409,608
Total equity	473,119	409,608
Limited Partner [Member] | Common units [Member] | Westlake [Member]
EQUITY
Limited Partners' Capital Account	49,195	48,774
Total equity	49,195	48,774
General Partner [Member] | Westlake [Member]
EQUITY
General partner—Westlake	(242,572)	(242,572)
Total equity	$ (242,572)	$ (242,572)