Partners' Equity (Incentive Distribution Rights) (Details)	12 Months Ended
Dec. 31, 2016
Equity [Abstract]
Percentage of minimum quarterly distribution partnership must pay to end subordination period	150.00%

Percentage Paid Of Minimum Quarterly Distribution Ending Subordination Period

No definition available.

Name:	wlkp_PercentagePaidOfMinimumQuarterlyDistributionEndingSubordinationPeriod
Namespace Prefix:	wlkp_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration