Long-Term Debt (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Long-term debt
Total debt	$ 1,165,460	$ 1,169,757
Less: current portion of long-term debt	(47,263)	(45,325)
Total long-term debt	1,118,197	1,124,432
Senior Subordinated Notes [Member]
Long-term debt
Senior notes, noncurrent	325,000	325,000
Revolving Credit Facility [Member]
Long-term debt
Line of Credit Facility, Amount Outstanding	27,000	27,000
Term Loan B, dated October 18, 2013 [Member] | Loans Payable [Member]
Long-term debt
Total debt	662,054	663,492
Term Loan C, Dated October 18, 2013 [Member] | Loans Payable [Member]
Long-term debt
Total debt	$ 151,406	$ 154,265