Company's Debt Maturities on Calendar Year Basis (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011		Dec. 31, 2010
Debt Instrument [Line Items]
Total	$ 633,389		$ 584,387
2012	322,423
2013	20,802
2014	47,000
2016	243,164
2.50% Convertible Notes
Debt Instrument [Line Items]
Total	243,164	[1]
2016	243,164	[1]
1.875% Convertible Notes
Debt Instrument [Line Items]
Total	278,955	[2]	262,716
2012	278,955	[2]
Ecko Note
Debt Instrument [Line Items]
Total	67,000		80,000
2012	10,000
2013	10,000
2014	47,000
Asset-Backed Notes
Debt Instrument [Line Items]
Total	44,270		70,650
2012	33,468
2013	$ 10,802

[1] Reflects the net debt carrying amount of the 2.50% Convertible Notes in the consolidated balance sheet as of December 31, 2011, in accordance with accounting for convertible notes. The principal amount owed to the holders of the Convertible Notes is $300.0 million.

[2] Reflects the net debt carrying amount of the 1.875% Convertible Notes in the consolidated balance sheet as of December 31, 2011, in accordance with accounting for convertible notes. The principal amount owed to the holders of the Convertible Notes is $287.5 million.