v3.19.3
Long-Term Debt - Components of Long-Term Debt (Details) - USD ($)
$ in Thousands
Sep. 30, 2019
Dec. 31, 2018
Debt Instrument [Line Items]    
Unamortized discount and debt issuance costs $ (15,720) $ (18,251)
Total long-term debt 631,520 628,989
Estimated fair value of total long-term debt outstanding 672,400 670,800
Senior Notes | 9.25% Senior Secured Notes, due 2023    
Debt Instrument [Line Items]    
Total long-term debt, before debt issuance costs and discount $ 645,000 645,000
Debt instrument, percentage rate 9.25%  
Senior Notes | 6.50% Notes, due 2021    
Debt Instrument [Line Items]    
Total long-term debt, before debt issuance costs and discount $ 2,240 $ 2,240
Debt instrument, percentage rate 6.50%