Long-Term Debt Long-Term Debt (Loss on Extinguishment of Debt) (Details) (USD $)	3 Months Ended
	Mar. 31, 2012		Mar. 31, 2011
Extinguishment of Debt [Line Items]
Face Amount Repaid or Retired	$ 75,500,000		$ 142,300,000
Debt Instrument, Decrease, Repayments	76,000,000		145,300,000
Gains (Losses) on Extinguishment of Debt	(2,611,000)	[1]	(6,946,000)	[1]
Term Loans [Member]
Extinguishment of Debt [Line Items]
Face Amount Repaid or Retired	70,500,000		110,000,000
Debt Instrument, Decrease, Repayments	70,500,000		110,000,000
Gains (Losses) on Extinguishment of Debt	1,900,000	[1]	2,700,000	[1]
Senior Notes [Member]
Extinguishment of Debt [Line Items]
Face Amount Repaid or Retired	5,000,000		32,300,000
Debt Instrument, Decrease, Repayments	5,500,000		35,300,000
Gains (Losses) on Extinguishment of Debt	$ 700,000	[1]	$ 4,200,000	[1]

[1] Including write-off of the discount and deferred financing costs related to the debt retired.