v2.4.0.6

Stockholders' Equity (Details) (USD $) | 12 Months Ended
--- | ---
Dec. 31, 2011 | Dec. 31, 2010 | Dec. 31, 2009
Stockholders' Equity [Abstract] |  |  |
Aggregate common stock dividends declared | $ 18,265,000 | $ 16,014,000 | $ 14,510,000
Description of common stock voting rights | Each share of common stock entitles the holder to one vote on all matters on which holders are permitted to vote, including the election of directors. There are no cumulative voting rights. |  |
Description of common stock subscription rights | The Company's common stock has no preemptive or conversion rights or other subscription rights. |  |
Common stock, redemption provision | 0 |  |
Common stock, sinking fund | $ 0 |  |

X
- Definition Description of voting rights of common stock. Includes eligibility to vote and votes per share owned. Include also, if any, unusual voting rights. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 129 -Paragraph 4 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21475-112644 + Details
Name: | us-gaap_CommonStockVotingRights
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Equity impact of common stock cash dividends declared by an entity during the period. This element includes paid and unpaid dividends declared during the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 Reference 2: 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=6959260&loc=d3e187085-122770 + Details
Name: | us-gaap_DividendsCommonStockCash
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | us-gaap_StockholdersEquityAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Description of other rights of common stock, including preemptive, conversion and other subscription rights. + References No definition available. + Details
Name: | wlk_CommonStockOtherRights
Namespace Prefix: | wlk_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Common Stock, Redemption Provision + References No definition available. + Details
Name: | wlk_CommonStockRedemptionProvision
Namespace Prefix: | wlk_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Sinking fund provision for common stock. + References No definition available. + Details
Name: | wlk_CommonStockSinkingFundProvision
Namespace Prefix: | wlk_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant