Accounts Receivable (Schedule Of Accounts Receivable) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Accounts Receivable, Net [Abstract]
Trade customers	$ 525,546us-gaap_AccountsReceivableGrossCurrent	$ 410,302us-gaap_AccountsReceivableGrossCurrent
Affiliates	437	315
Allowance for doubtful accounts	(13,468)	(11,741)
Receivables from trade customers and affiliates, net	512,515	398,876
Federal and state taxes	8,919us-gaap_IncomeTaxesReceivable	20,820us-gaap_IncomeTaxesReceivable
Other	39,232wlk_OtherReceivablesCurrent	8,761wlk_OtherReceivablesCurrent
Accounts receivable, net	$ 560,666us-gaap_ReceivablesNetCurrent	$ 428,457us-gaap_ReceivablesNetCurrent

Amounts due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer) for goods or services (including trade receivables) that have been delivered or sold in the normal course of business.

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Amount of receivables arising from transactions with related parties due within one year or the normal operating cycle, if longer.

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A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

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Carrying amount due within one year of the balance sheet date (or one operating cycle, if longer) from tax authorities as of the balance sheet date representing refunds of overpayments or recoveries based on agreed-upon resolutions of disputes.

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- Definition

The total amount due to the entity within one year of the balance sheet date (or one operating cycle, if longer) from outside sources, including trade accounts receivable, notes and loans receivable, as well as any other types of receivables, net of allowances established for the purpose of reducing such receivables to an amount that approximates their net realizable value.

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Amount due from other third-parties, or arising from transactions not separately disclosed, within one year of the balance sheet date (or the normal operating cycle, whichever is longer).

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No definition available.

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The aggregate of amounts due from customers or clients, within one year of the balance sheet date (or one operating cycle, if longer), for goods or services that have been delivered or sold in the normal course of business, and amounts due from related parties (affiliates) payable within one year of the balance sheet, reduced to their estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.

+ References

No definition available.

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