XML 129 R114.htm IDEA: XBRL DOCUMENT v3.20.4

Segment and Geographic Information (Narrative) (Details)	12 Months Ended
	Dec. 31, 2020 Segment plant customer	Dec. 31, 2019 customer	Dec. 31, 2018 customer
Segment Reporting Information [Line Items]
Number of segments | Segment	2
Number of Building Product Facilities | plant	37
Olefins [Member]
Segment Reporting Information [Line Items]
Number of major customers	0	0	0
Vinyls [Member]
Segment Reporting Information [Line Items]
Number of major customers	0	0	0

X

- 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.

+ References

No definition available.

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- Definition

Concentration Risk, Number of Major Customers

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No definition available.

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- Definition

Represents the number of company plants that manufacture building products.

+ References

No definition available.

+ Details

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Namespace Prefix:	wlk_
Data Type:	xbrli:integerItemType
Balance Type:	na
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X

- Definition

Number of segments

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No definition available.

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X

- Details

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X

- Details

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