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Equity - Additional Information (Details) - $ / shares | 12 Months Ended |
--- | --- | ---
Dec. 31, 2018 | Dec. 31, 2017
Class of Stock [Line Items] |  |
Common stock, issued (in shares) | 35,687,000 | 35,650,000
Common stock, outstanding (in shares) | 35,687,000 | 35,650,000
Common stock, par value (in dollars per share) | $ 0.001 | $ 0.001
Nonvested (in shares) | 400,000 |
Shares authorized (in shares) | 250,000,000.0 | 250,000,000
Class of Warrant, Number of Securities issued for Each Warrant | 1 |
Series A Warrants |  |
Class of Stock [Line Items] |  |
Issuance of common stock (in shares) | 4,600,000 |
Exercise price of warrants (in usd per share) | $ 41.34 |
Series B Warrants |  |
Class of Stock [Line Items] |  |
Issuance of common stock (in shares) | 2,000,000.0 |
Exercise price of warrants (in usd per share) | $ 42.03 |

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