Per unit of ownership amount of cash distributions declared to unit-holder of a limited partnership (LP).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 272
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70478-108055

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 272
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70434-108055

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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- Definition

Amount of incentive obligation paid in cash or stock during the period to a limited liability corporation managing member or limited partnership general partner.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

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- Definition

Incentive Distribution Rights, Target Distribution Per Unit Requiring Marginal Percentage Distribution to IDR Holders

+ References

No definition available.

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- Definition

Minimum Quarterly Distribution Per Unit

+ References

No definition available.

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- Details

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Distributions and Net Income Per Limited Partner Unit (Narrative) (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended
	Feb. 23, 2018	Dec. 31, 2017
Westlake Chemical OpCo LP [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Distribution declared per unit (usd per share)	$ 0.3864
Cash Distribution [Member] \| IDR Holders [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Incentive distribution	$ 614
Common units [Member] \| Cash Distribution [Member]
Subsequent Event [Line Items]
Minimum Quarterly Distribution Per Unit		$ 0.2750
Common and Subordinated units [Member] \| Cash Distribution [Member]
Subsequent Event [Line Items]
Minimum quarterly distribution per unit (usd per share)		$ 0.3163