Subsequent Event (Details) - Jul. 24, 2015 - Subsequent event - Axane, S.A. - HyPulsion - USD ($) $ in Millions |
Total |
|---|---|
| Subsequent Event [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 | 4,781,250 |
| Additional shares issuable in certain circumstances | 3,105,348 |