Fair Value Measurement (Carrying Values And Fair Values Of The Company's Financial Instruments) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term Debt	$ 2,153,997	$ 2,153,315
Long-term Debt, Fair Value	2,277,315	2,280,654
Term-A Facility [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term Debt	876,575	876,358
Long-term Debt, Fair Value	880,440	876,154
7.75% Senior Notes [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term Debt	687,683	687,423
Long-term Debt, Fair Value	795,375	801,500
4.75% Senior Notes [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term Debt	589,739	589,534
Long-term Debt, Fair Value	$ 601,500	$ 603,000