Interest rate stated in the contractual debt agreement.

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-Number 210

-Section 02

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-Topic 210

-SubTopic 10

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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.

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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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Debt (Schedule Of Obligations Under Debt Arrangements) (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Feb. 08, 2013	Dec. 31, 2012	Nov. 18, 2010
Debt Instrument [Line Items]
Senior secured credit facility	$ 319,100		$ 500,000
Senior unsecured notes	700,835		350,895
Senior unsecured notes, stated rate		5.75%		7.875%
Total long-term debt	1,019,935		850,895
7.875% Senior Unsecured Notes [Member]
Debt Instrument [Line Items]
Senior unsecured notes	350,835		350,895
Senior unsecured notes, stated rate	7.875%
Senior unsecured notes, unamortized premium	835		895
Five Point Seventy Five Percentage Senior Unsecured Notes [Member]
Debt Instrument [Line Items]
Senior unsecured notes	$ 350,000		$ 0
Senior unsecured notes, stated rate	575000.00%