Long-Term Debt - Components of Long-Term Debt (Details) - USD ($) $ in Thousands |
Jun. 30, 2020 |
Dec. 31, 2019 |
|---|---|---|
| Debt Instrument [Line Items] | ||
| Unamortized discount and debt issuance costs | $ (12,993) | $ (14,834) |
| Total long-term debt, net of current portion | 632,007 | 632,406 |
| Current portion of long-term debt | 2,240 | 0 |
| Total long-term debt, including current portion | 634,247 | 632,406 |
| Estimated fair value of total long-term debt outstanding | 632,100 | 673,800 |
| Senior Notes | 9.25% Senior Secured Notes, due June 2023 | ||
| Debt Instrument [Line Items] | ||
| Total long-term debt, net of current portion, before debt issuance costs and discount | $ 645,000 | 645,000 |
| Debt instrument, percentage rate | 9.25% | |
| Senior Notes | 6.50% Notes, due April 2021, net of current portion | ||
| Debt Instrument [Line Items] | ||
| Total long-term debt, net of current portion, before debt issuance costs and discount | $ 0 | $ 2,240 |
| Current portion of long-term debt | $ 2,200 | |
| Debt instrument, percentage rate | 6.50% |