Long-Term Obligations (Amount Of Interest Expense Recognized) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Debt Instrument [Line Items]
Amortization of discount on convertible debentures	$ 19,835	$ 18,495	$ 17,246
Series A [Member]
Debt Instrument [Line Items]
Contractual coupon interest	7,562	7,562	7,562
Amortization of discount on convertible debentures	10,214	9,541	8,913
Interest expense	17,776	17,103	16,475
Series B [Member]
Debt Instrument [Line Items]
Contractual coupon interest	7,562	7,562	7,562
Amortization of discount on convertible debentures	9,621	8,954	8,333
Interest expense	$ 17,183	$ 16,516	$ 15,895