• Filing Date: 2018-03-07
  • Form Type: 10-K
  • Description: Annual report
v3.8.0.1
Long-Term Debt - Summary of Long-Term Debt (Detail) - USD ($)
$ in Thousands
Dec. 31, 2017
Mar. 03, 2017
Dec. 31, 2016
Mar. 31, 2016
Dec. 31, 2013
Debt Instrument [Line Items]          
Total principal amount $ 260,061   $ 147,985    
Less: unamortized discount and issuance costs (22,226)   (9,122)    
Total long-term debt 237,835   138,863    
Senior Notes [Member]          
Debt Instrument [Line Items]          
Total principal amount     40,250    
3.875% Convertible Senior Notes [Member]          
Debt Instrument [Line Items]          
Total principal amount 89,990   89,990 $ 89,990 $ 103,000
4.25% Convertible Senior Notes [Member]          
Debt Instrument [Line Items]          
Total principal amount 143,750 $ 143,750      
3.95% Promissory Note [Member]          
Debt Instrument [Line Items]          
Total principal amount 9,360        
4% Promissory Note [Member]          
Debt Instrument [Line Items]          
Total principal amount 8,348   8,821    
3.75% Promissory Note [Member]          
Debt Instrument [Line Items]          
Total principal amount $ 8,613   $ 8,924