Long-Term Debt (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Debt Instrument [Line Items]
Total Debt	$ 583,811	$ 587,561
Current portion, long-term debt	26,250	22,500
Long-term debt	557,561	565,061
Senior Secured Revolving Credit Facility
Debt Instrument [Line Items]
Total Debt	50,000	50,000
Senior Secured Term Loan A
Debt Instrument [Line Items]
Total Debt	273,750	277,500
Senior Secured Convertible Notes due 2033, net of discount
Debt Instrument [Line Items]
Total Debt	61	61
Senior Notes due 2021
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	6.625%	6.625%
Total Debt	$ 260,000	$ 260,000

Interest rate stated in the contractual debt agreement.

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