v2.4.0.6

Long-Term Debt (Debt Covenants And Credit Facility) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2011 | Dec. 31, 2011 | Dec. 31, 2010 | Dec. 31, 2009
Debt Instrument [Line Items] |  |  |  |
Quarterly dividend, per share | $ 0.0738 | $ 0.2746 | $ 0.2420 | $ 0.2200
Investment in joint ventures |  | $ 200,000 |  |
Suzhou Huasu Plastics Co. Ltd. [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Investment in joint ventures |  | 55,000 |  |
Debt Covenant [Member] | Senior Notes [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Maximum percentage of income distribution |  | 50.00% |  |
Maximum distribution percentage of specified net cash proceeds |  | 100.00% |  |
Minimum [Member] | Senior Secured Revolving Credit Facility [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Fixed charge coverage ratio for debt covenant |  | 1.0 |  |
Minimum [Member] | Debt Covenant [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Fixed charge coverage ratio |  | 2.0 |  |
Minimum [Member] | Debt Covenant [Member] | Senior Secured Revolving Credit Facility [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Fixed charge coverage ratio for debt covenant |  | 1.0 |  |
Maximum [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Maximum unrestricted distributions allowable |  | 100,000 |  |
Maximum [Member] | Debt Covenant [Member] | Senior Notes [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Limitation exception for the payment of quarterly dividend |  | 0.20 |  |
25% Of Total Bank Commitments [Member] | Minimum [Member] | Senior Secured Revolving Credit Facility [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Borrowing availability of bank commitments, minimum | 100,000 | 100,000 |  |
Percentage of borrowing availability of bank commitments | 25.00% | 25.00% |  |
17.5% Of Total Bank Commitments [Member] | Senior Secured Revolving Credit Facility [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Maximum distributions allowable |  | 25,000 |  |
17.5% Of Total Bank Commitments [Member] | Minimum [Member] | Senior Secured Revolving Credit Facility [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Borrowing availability of bank commitments, minimum | $ 70,000 | $ 70,000 |  |
Percentage of borrowing availability of bank commitments | 17.50% | 17.50% |  |

X
- Definition Aggregate dividends declared during the period for each share of common stock outstanding. + 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
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X
- Details
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Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Represents the minimum borrowing availability that must be maintained under the revolving credit facility in order to make acquisitions or investments. + References No definition available. + Details
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Namespace Prefix: | wlk_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The calculated fixed charge coverage ratio for the revolving credit facility. + References No definition available. + Details
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Namespace Prefix: | wlk_
Data Type: | xbrli:decimalItemType
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- Definition The calculated fixed charge coverage ratio for the senior notes. + References No definition available. + Details
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- Definition Represents the minimum borrowing availability, as a percentage of total bank commitments, that must be maintained under the revolving credit facility in order to make acquisitions or investments. + References No definition available. + Details
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- Definition Maximum distribution percentage of specified net cash proceeds received after a stated period plus other adjustments, and subject to certain other distribution terms. + References No definition available. + Details
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- Definition The maximum investment amount in specified joint ventures allowed under debt covenants. + References No definition available. + Details
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Data Type: | xbrli:monetaryItemType
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- Definition Maximum percentage of income distribution, subject to certain other distribution terms. + References No definition available. + Details
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- Definition The maximum specified distribution allowed under debt covenants. + References No definition available. + Details
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Namespace Prefix: | wlk_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The maximum unrestricted distribution allowed under debt covenants. Distributions in excess of this amount are subject to certain restrictions. + References No definition available. + Details
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Balance Type: | debit
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- Definition The maximum unrestricted payment per share allowed under debt covenants for the quarterly dividend. + References No definition available. + Details
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Period Type: | duration