Fair Value Measurements - Level III (Details) - USD ($) $ in Thousands |
12 Months Ended | |
|---|---|---|
Dec. 31, 2016 |
Dec. 31, 2015 |
|
| Long-term Debt | Secured Loan Arrangement | ||
| Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] | ||
| Beginning balance | $ 20,964 | |
| Settled | (20,000) | |
| Long-term Debt | Nonperating Expenses | Secured Loan Arrangement | ||
| Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] | ||
| Change in fair value | (964) | |
| Warrants | ||
| Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] | ||
| Beginning balance | $ 3,649 | 2,232 |
| Settled | (240) | |
| Change in fair value | 143 | 1,657 |
| Ending balance | $ 3,792 | $ 3,649 |