Company's Debt Maturities on Calendar Year Basis (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013		Dec. 31, 2012
Debt Instrument [Line Items]
Total	$ 1,427,319		$ 911,718
2014	61,250
2015	61,250
2016	328,263
2017	61,250
2018	384,668
Thereafter	530,638
Senior Secured Notes
Debt Instrument [Line Items]
Total	836,888		600,000
2014	61,250
2015	61,250
2016	61,250
2017	61,250
2018	61,250
Thereafter	530,638
1.50% Convertible Notes
Debt Instrument [Line Items]
Total	323,418	[1]
2018	323,418	[1]
2.50% Convertible Notes
Debt Instrument [Line Items]
Total	267,013	[2]	254,718
2016	$ 267,013	[2]

[1] Reflects the net debt carrying amount of the 1.50% Convertible Notes in the consolidated balance sheet as of December 31, 2013, in accordance with accounting for convertible notes. The principal amount owed to the holders of the 1.50% Convertible Notes is $400.0 million.

[2] Reflects the net debt carrying amount of the 2.50% Convertible Notes in the consolidated balance sheet as of December 31, 2013, in accordance with accounting for convertible notes. The principal amount owed to the holders of the 2.50% Convertible Notes is $300.0 million.