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Preferred Stock and Common Stock Warrants - Preferred Stock (Details) $ / shares in Units, $ in Thousands |  | 1 Months Ended | 3 Months Ended
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Apr. 15, 2019 USD ($) | Sep. 30, 2018 USD ($) $ / shares shares | Aug. 31, 2018 USD ($) $ / shares shares | Mar. 31, 2019 USD ($) $ / shares
Convertible Preferred Stock |  |  |  |
Stockholders’ Equity |  |  |  |
Temporary equity, issued value per share |  |  |  | 1,000
Dividends, temporary equity percentage |  |  |  | 12.00%
Series A Convertible Preferred stock |  |  |  |
Stockholders’ Equity |  |  |  |
Number of shares issued | shares |  |  | 50,000 |
Convertible preferred stock, par value |  |  | $ 0.0001 |
Temporary equity, issued value per share |  |  | 1,000 |
Aggregate purchase price | $ |  |  | $ 50,000 |
Additional shares issued as origination fees | shares |  |  | 1,000 |
Paid-in-kind dividends | $ | $ 1,600 |  |  | $ 1,600
Series B Convertible Preferred stock |  |  |  |
Stockholders’ Equity |  |  |  |
Number of shares issued | shares |  | 29,055 |  |
Convertible preferred stock, par value |  | $ 0.0001 |  |
Temporary equity, issued value per share |  | 1,000 |  |
Aggregate purchase price | $ |  | $ 29,055 |  |
Additional shares issued as origination fees | shares |  | 581 |  |
Paid-in-kind dividends | $ | $ 900 |  |  | $ 900

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- Definition Amount of paid and unpaid preferred stock dividends declared with the form of settlement in payment-in-kind (PIK). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 405 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6957935&loc=d3e64057-112817 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 + Details
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