Acquisitions - HyPulsion (Details) - HyPulsion - USD ($) $ in Millions |
Aug. 26, 2015 |
Jun. 24, 2015 |
Jul. 31, 2015 |
|---|---|---|---|
| Business Acquisition [Line Items] | |||
| Percentage of voting interest acquired | 80.00% | ||
| Value of shares of common stock issued | $ 11.5 | ||
| Number of shares of common stock issued | 1,613,289 | 4,781,250 |