Net Income Per Limited Partner Unit (Income In Excess Of Distribution) (Details) - Jun. 30, 2015 - USD ($) $ in Thousands	Total	Total
Net income attributable to Westlake Chemical Partners LP	$ 10,443	$ 18,943
Distribution declared	7,874	15,529
Net income in excess of distribution	2,569	3,414
Common units [Member]
Net income attributable to Westlake Chemical Partners LP	5,548	10,064
Distribution declared	4,183	8,248
Net income in excess of distribution	1,365	1,816
Subordinated units [Member]
Net income attributable to Westlake Chemical Partners LP	4,895	8,879
Distribution declared	3,691	7,281
Net income in excess of distribution	$ 1,204	$ 1,598