Fair Value Measurement (Carrying Values And Fair Values Of The Company's Financial Instruments) (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt	$ 2,968,190	$ 2,667,808
Long-term Debt, Fair Value	2,997,563	2,708,475
Term-A Facility [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt	1,351,480	1,386,869
Long-term Debt, Fair Value	1,341,620	1,370,850
5.00% Senior Notes [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt	980,430
Long-term Debt, Fair Value	1,006,250
7.75% Senior Notes [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt	44,981	689,910
Long-term Debt, Fair Value	48,193	737,625
4.75% Senior Notes [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt	591,299	591,029
Long-term Debt, Fair Value	$ 601,500	$ 600,000