Debt And Interest Expense (Carrying Amounts Of Liability And Equity Components) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Apr. 16, 2013	Dec. 31, 2012	Aug. 15, 2007
Debt Disclosure [Abstract]
Debt Instrument, Unamortized Discount (Premium), Net	$ 686,221		$ 686,221
deferred tax on debenture discount	(267,225)		267,225
Carrying amount of equity component (net of issuance costs of $14,449)	418,996		418,996
Principal amount of convertible debentures	1,250,000	750,000	1,250,000	1,250,000
Unamortized discount of liability component	(654,948)		(663,589)
Carrying amount of liability component	595,052		586,411
Contingent interest derivative	29,004		11,203
Convertible Debt	$ 624,056		$ 597,614