The maximum amount of contingent interest that will accrue per annum of the average trading price, as outlined in the indenture.

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- Definition

Exchange offer terms

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- Definition

Including current and noncurrent portions, the carrying value of the principal amount of debt extinguished

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- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. Fair value of convertible debt at the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Convertible Security

-URI http://asc.fasb.org/extlink&oid=6509036

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- Definition

The price per share of the conversion feature embedded in the debt instrument.

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The ratio applied to the debt for purposes of determining the number of shares of the equity security into which the debt will be converted.

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-Glossary Conversion Rate

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Description of the conversion terms of a debt instrument which may include the conversion ratio (including all potential conversion ratios if contingently adjustable), type of debt or equity security into which the debt is convertible, the dollars of debt or the number of shares into which the instrument is convertible (or potentially convertible into), the conversion period, any contingencies associated with the conversion terms, and the existence and amount of a beneficial conversion feature.

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- Definition

The stated principal amount of the debt instrument at time of issuance, which may vary from the carrying amount because of unamortized premium or discount.

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- Definition

Interest rate stated in the contractual debt agreement.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Date when the debt instrument is scheduled to be fully repaid, which may be presented in a variety of ways (year, month and year, day, month and year, quarter, etc.).

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Represents the noncurrent portion of deferred tax liabilities, which result from applying the applicable tax rate to net taxable temporary differences pertaining to each jurisdiction to which the entity is obligated to pay income tax. A noncurrent taxable temporary difference is a difference between the tax basis and the carrying amount of a noncurrent asset or liability in the financial statements prepared in accordance with generally accepted accounting principles. In a classified statement of financial position, an enterprise separates deferred tax liabilities and assets into a current amount and a noncurrent amount. Deferred tax liabilities and assets are classified as current or noncurrent based on the classification of the related asset or liability for financial reporting. A deferred tax liability or asset that is not related to an asset or liability for financial reporting, including deferred tax assets related to carryforwards, are classified according to the expected reversal date of the temporary difference.

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Debt And Capital Lease Obligations (Convertible Debentures) (Details) (USD $)			9 Months Ended	12 Months Ended
	Sep. 30, 2011	Dec. 31, 2010	Sep. 30, 2011 5.75% Junior Subordinated Convertible Debentures [Member]	Dec. 31, 2009 5.75% Junior Subordinated Convertible Debentures [Member]	Dec. 31, 2009 4.875% Unsecured Senior Notes [Member]
Debt Instrument
Debt Instrument, Face Amount			$ 125,000,000		$ 250,000,000
Debt Instrument, Interest Rate, Stated Percentage			5.75%		4.875%
Debt Instrument, Maturity Date			Sep. 15, 2029		Dec. 15, 2009
Exchange offer terms				1,020	1,000
Unsecured debt, principal amount of debt extinguished					122,500,000
Liability component of convertible debt recognized at issuance				56,300,000
Deferred tax impact on convertible debt	$ 153,800,000	$ 76,400,000		$ 32,700,000
Debt Instrument, Convertible, Conversion Price				$ 12.07
Debt Instrument, Convertible, Conversion Ratio				82.82
Debt Instrument, Convertible, Terms of Conversion Feature				1000
Contingent Interest Component, Maxiumum			0.75%