Deferred Engineering Costs - Additional Information (Detail) - USD ($) $ in Thousands |
Jun. 30, 2018 |
Dec. 31, 2017 |
|---|---|---|
| Deferred Costs [Abstract] | ||
| Deferred engineering costs | $ 44,100 | $ 18,000 |
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- References No definition available.
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- Definition The carrying amount of deferred costs. No definition available.
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