| Common Stock, Share-based Awards and Warrants - Warrants by Exercise Price (Details) | 6 Months Ended | 
|---|---|
| Jun. 30, 2018  $ / shares  shares | |
| Penny Warrants | |
| Share-based Compensation, Shares Authorized under Equity Instruments Other Than Options, Exercise Price Range [Line Items] | |
| Number of warrants (in shares) | shares | 18,065,775 | 
| Weighted Average Exercise price (in usd per share) | $ / shares | $ 0.01 | 
| Weighted Average Remaining Contractual Term (in years) | 9 years 8 months 12 days | 
| Market Warrants | |
| Share-based Compensation, Shares Authorized under Equity Instruments Other Than Options, Exercise Price Range [Line Items] | |
| Number of warrants (in shares) | shares | 13,000,000 | 
| Weighted Average Exercise price (in usd per share) | $ / shares | $ 1.57 | 
| Weighted Average Remaining Contractual Term (in years) | 9 years 8 months 12 days | 
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- Definition Class of Warrant Or Right, Term No definition available. 
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- Definition Share-based Compensation, Shares Authorized under Equity Instruments Other Than Options, Exercise Price Range [Line Items] No definition available. 
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- Definition Exercise price per share or per unit of warrants or rights outstanding. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition Number of warrants or rights outstanding. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Details 
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- Details 
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