Debt (Schedule Of Obligations Under Debt Arrangements) (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Debt Instrument [Line Items]
Senior secured credit facility	$ 483,000	$ 409,300
Senior unsecured notes	350,924	250,000
Total long-term debt	833,924	659,300
7.875% Senior Unsecured Notes [Member]
Debt Instrument [Line Items]
Senior unsecured notes	350,924	250,000
Senior unsecured notes, stated rate	7.875%
Senior unsecured notes, unamortized premium	$ 924	$ 0

Interest rate stated in the contractual debt agreement.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

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The amount of debt premium that was originally recognized at the issuance of the instrument that has yet to be amortized.

+ References

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-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

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Sum of the carrying values as of the balance sheet date of all long-term debt, which is debt initially having maturities due after one year from the balance sheet date or beyond the operating cycle, if longer, but excluding the portions thereof scheduled to be repaid within one year (current maturities) or the normal operating cycle, if longer, and after deducting unamortized discount or premiums, if any.

+ References

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

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Carrying value as of the balance sheet date of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer), excluding the current portion, if any. Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

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Carrying value as of the balance sheet date of uncollateralized debt obligation (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion.

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