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v3.19.3

Nature of the Business and Basis of Presentation (Details) $ / shares in Units, $ in Thousands |  |  |  |  | 1 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | --- | --- | --- | --- | ---
May 03, 2019 | Nov. 05, 2018 USD ($) $ / shares shares | Nov. 02, 2018 USD ($) | Apr. 05, 2018 USD ($) $ / shares shares | Nov. 30, 2018 USD ($) $ / shares shares | Apr. 30, 2018 USD ($) $ / shares shares | Sep. 30, 2018 USD ($) | Dec. 31, 2018 USD ($) segment | Dec. 31, 2017 USD ($)
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |
Proceeds from issuance of preferred stock, net of issuance costs | $ |  |  | $ 15,000 |  |  |  | $ 31,000 | $ 122,223 | $ 25,000
Reverse stock split ratio (as a percent) | 0.1245 |  |  |  |  |  |  |  |
Number of operating segment | segment |  |  |  |  |  |  |  | 1 |
Series A-3 preferred stock |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |
Issuance of stock (in shares) | shares |  |  |  | 28,181,819 |  | 28,181,819 |  |  |
Share price (in dollars per share) | $ / shares |  |  |  | $ 1.10 |  | $ 1.10 |  |  |
Proceeds from issuance of preferred stock, net of issuance costs | $ |  |  |  | $ 31,000 |  | $ 31,000 |  |  |
Series B-1 preferred stock |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |
Issuance of stock (in shares) | shares |  | 15,052,117 |  |  | 15,052,117 |  |  |  |
Share price (in dollars per share) | $ / shares |  | $ 1.59 |  |  |  |  |  |  |
Series B-2 preferred stock |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |
Issuance of stock (in shares) | shares |  | 34,276,734 |  |  | 34,276,734 |  |  |  |
Share price (in dollars per share) | $ / shares |  | $ 1.59 |  |  |  |  |  |  |
Series B-3 preferred stock |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |
Issuance of stock (in shares) | shares |  | 7,500,000 |  |  | 7,500,000 |  |  |  |
Share price (in dollars per share) | $ / shares |  | $ 2.00 |  |  | $ 2.00 |  |  |  |
Proceeds from issuance of preferred stock, net of issuance costs | $ |  | $ 93,400 |  |  | $ 15,000 |  |  |  |

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- Definition Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues. + References No definition available. + Details
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