For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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

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Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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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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Related Party Transactions (General) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Aug. 04, 2014
Related Party Transaction [Line Items]
Income Taxes Paid	$ 655	$ 711	$ 716
Affiliated Entity [Member] \| Reimbursement to Parent for State Tax [Member] \| Westlake [Member]
Related Party Transaction [Line Items]
Income Taxes Paid	$ 293	$ 418	$ 415
Investee [Member] \| Westlake [Member] \| Site Lease Agreement [Member] \| Westlake Chemical OpCo LP [Member]
Related Party Transaction [Line Items]
Term of operating lease				50 years
Revenue Benchmark [Member] \| Customer Concentration Risk [Member] \| Westlake [Member] \| Affiliated Entity [Member]
Related Party Transaction [Line Items]
Concentration Risk, Percentage	85.90%	83.60%	83.00%