Organization and Description of Business - Series A Perpetual Convertible Preferred Stock (Details) - USD ($) $ / shares in Units, $ in Thousands |
Oct. 18, 2016 |
Aug. 25, 2016 |
Dec. 31, 2016 |
Dec. 31, 2015 |
|---|---|---|---|---|
| Series A Perpetual Conertible Preferred Stock | ||||
| Series A preferred stock, par value (in dollars per share) | $ 0.001 | $ 0.001 | ||
| Series A preferred stock | ||||
| Series A Perpetual Conertible Preferred Stock | ||||
| Shares issued (in shares) | 1.84 | |||
| Dividend rate (as a percent) | 8.00% | 8.00% | ||
| Series A preferred stock, par value (in dollars per share) | $ 0.001 | |||
| Preferred stock, share price (in dollars per share) | $ 50 | |||
| Gross proceeds form sale of preferred stock | $ 92,000 | |||
| Underwriting discounts and commissions | $ 3,680 |