Quarterly report pursuant to Section 13 or 15(d)

Debt Instruments - Schedule of long-term debt (Details)

v3.5.0.2
Debt Instruments - Schedule of long-term debt (Details) - USD ($)
$ in Thousands
Jun. 30, 2016
Dec. 31, 2015
Debt Instrument [Line Items]    
Long-term debt, net $ 243,483 $ 234,577
Convertible debt | 1.75% convertible senior notes due 2020    
Debt Instrument [Line Items]    
1.75% convertible senior notes due 2020 345,000 345,000
Unamortized discount on convertible senior notes (101,517) (110,423)
Long-term debt, net $ 243,483 $ 234,577