XML 81 R68.htm IDEA: XBRL DOCUMENT v3.3.1.900
Convertible Senior Notes - Additional Information (Detail) - USD ($)
$ / shares in Units, $ in Thousands
1 Months Ended 12 Months Ended
Nov. 01, 2014
Jan. 31, 2016
Jun. 30, 2014
Jul. 31, 2013
Nov. 30, 2009
Dec. 31, 2015
Dec. 31, 2014
Nov. 01, 2014
Dec. 31, 2013
Debt Instrument [Line Items]                  
Gain on debt extinguishment                 $ 84
Debt discount                 (2,802)
Payment for repurchase of common stock     $ 24,000     $ 13,193 $ 24,000    
Repurchase of common stock under prepaid forward repurchase agreement, shares     3,112,840            
Repayments of debt             39,000   61,000
4.50% Convertible senior notes (due 2014)                  
Debt Instrument [Line Items]                  
Long term debt, face amount         $ 100,000        
Frequency of interest payment           Semi-annually      
Debt instrument, maturity date         Nov. 01, 2014        
Debt instrument, interest rate         4.50%        
Debt discount         $ 13,700        
Interest expenses associated with amortization of equity component           $ 0 $ 900   2,000
Debt issuance cost written off amount                 600
Repurchase of related equity component                 2,800
Debt discount written off amount                 $ 2,200
Repayments of debt $ 39,000                
Debt instrument repurchase amount       $ 61,000          
4.25% Convertible Senior Notes (due 2018)                  
Debt Instrument [Line Items]                  
Long term debt, face amount       $ 100,000          
Frequency of interest payment           Semi-annually      
Debt instrument, maturity date       Aug. 01, 2018          
Debt instrument, interest rate       4.25%   4.25% 4.25%    
Gain on debt extinguishment       $ 100          
Conversion rate in share per $1000 principal amount of notes       114.3674          
Debt instrument, conversion rate       $ 8.74          
Net proceeds from debt instrument       $ 96,000          
4.875% Convertible Senior Notes (due 2020)                  
Debt Instrument [Line Items]                  
Long term debt, face amount     $ 115,000            
Frequency of interest payment           Semi-annually      
Debt instrument, maturity date     Jun. 01, 2020            
Debt instrument, interest rate     4.875%     4.875% 4.875%    
Conversion rate in share per $1000 principal amount of notes     103.7613            
Debt instrument, conversion rate     $ 9.64            
Net proceeds from debt instrument     $ 110,400            
Payment for repurchase of common stock     $ 24,000            
Repurchase of common stock under prepaid forward repurchase agreement, shares     3,100,000            
Repayments of debt               $ 39,000  
4.875% Convertible Senior Notes (due 2020) | Subsequent Event                  
Debt Instrument [Line Items]                  
Payment for repurchase of common stock   $ 2,000              
Repayments of debt   $ 2,000