EARNINGS (LOSS) PER SHARE - Additional Information (Detail) (USD $)
In Millions, unless otherwise specified
Mar. 31, 2015
Dec. 31, 2014
3.0% Convertible Senior Notes Due 2015    
Debt Instrument [Line Items]    
Convertible senior notes, aggregate principal amount payable $ 114.4 $ 114.4
Convertible senior notes, interest rate 3.00% 3.00%
1.625% Convertible Senior Notes Due 2019    
Debt Instrument [Line Items]    
Convertible senior notes, aggregate principal amount payable $ 402.5 $ 402.5
Convertible senior notes, interest rate 1.625% 1.625%