The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4297-108586

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3536-108585

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The increase (decrease) during the reporting period in the amount owed by the reporting entry in the form of loans and obligations (generally evidenced by promissory notes) made by the following types of related parties: a parent company and its subsidiaries; subsidiaries of a common parent; an entity and trust for the benefit of employees, such as pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management, an entity and its principal owners, management, or member of their immediate families, affiliates, or other parties with the ability to exert significant influence.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585

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- Definition

The amount of cash paid for interest during the period net of cash paid for interest that is capitalized.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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- Definition

Cash Transferred In Notes Payable Settlement, Related Parties

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- Definition

Increase (Decrease) in Capital Expenditure Accrual

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Interest Incurred, Added to Debt Outstanding

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Supplemental Information (Cash Flow Information) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Related Party Transaction [Line Items]
Reduction in capital expenditure accrual	$ (14,552,000)	$ (418,000)	$ (7,937,000)
Interest Paid, Net	9,538,000	1,366,000
Income Taxes Paid	1,264,000	0
Westlake [Member] \| Affiliated Entity [Member]
Related Party Transaction [Line Items]
Related party notes payable deemed settled through net investment		238,600,000
Cash transferred in related party notes payable settlement		0
Predecessor [Member] \| Westlake [Member] \| Affiliated Entity [Member]
Related Party Transaction [Line Items]
Interest incurred, added to principal on promissory notes outstanding		$ 9,315,000
State and Local Jurisdiction [Member]
Related Party Transaction [Line Items]
Income Taxes Paid	231,000
Reimbursement to Parent for State Tax [Member] \| Westlake [Member] \| Affiliated Entity [Member]
Related Party Transaction [Line Items]
Income Taxes Paid	$ 1,033,000