The carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

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Interest rate stated in the contractual debt agreement.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Carrying amount as of the balance sheet date, which is the cumulative amount paid and (if applicable) the fair value of any noncontrolling interest in the acquiree, adjusted for any amortization recognized prior to the adoption of any changes in generally accepted accounting principles (as applicable) and for any impairment charges, in excess of the fair value of net assets acquired in one or more business combination transactions.

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The maximum amortization period of finite-lived intangible assets.

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The net balance of inventory exchanges, settled in like-kind quantities and valued at lower of cost or market, with third parties.

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Description Of Business And Significant Accounting Policies (Narrative) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011 years	Dec. 31, 2010	Dec. 31, 2009
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Undistributed earnings included in retained earnings	$ 14,031
Capitalized interest	693	22	123
Goodwill	29,990	29,990
Maturity	2016
Amortization period, minimum (in years)	3
Amortization period, maximum (in years)	6
Other assets amortization period, minimum (in years)	2
Other assets amortization period, maximum (in years)	20
Exchange receivable (payable), net	14,557	950
Removal And Disposal Of Hazardous Materials [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Asset retirement obligation recorded	$ 0
PVC Joint Venture In China [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Ownership interest	59.00%
Natural Gas Pipeline Joint Venture [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Ownership interest	50.00%
6 1/2% Senior Notes Due 2035 [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Stated interest rate	6.50%
Maturity	2035
GO Zone 6 3/4% Senior Notes Due 2032 [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Stated interest rate	6.75%	6.75%
Maturity	2032