XML 48 R33.htm IDEA: XBRL DOCUMENT
v3.20.4

Description of Business and Significant Accounting Policies (Tables) | 12 Months Ended
--- | ---
Dec. 31, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract] |
Schedule of Estimated Useful Lives of Assets |
Classification |  | Years
Buildings and improvements |  | 40
Plant and equipment |  | 10-25
Other |  | 3-15

X
- References No definition available. + Details
Name: | us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Table of estimated useful lives of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale. + References No definition available. + Details
Name: | wlk_ScheduleOfEstimatedUsefulLivesOfAssetsTableTextBlock
Namespace Prefix: | wlk_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration