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Loss per Share (Details) - Series C Convertible Preferred Stock [Member] - USD ($) | 3 Months Ended | 9 Months Ended |  |
--- | --- | --- | --- | ---
Sep. 30, 2019 | Sep. 30, 2019 | Dec. 31, 2018 | Sep. 30, 2018
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items] |  |  |  |
Preferred stock conversion price (in dollars per share) | $ 39.93 | $ 39.93 |  |
Preferred stock conversion price reduced (in dollars per share) | $ 7.50 | $ 7.50 |  |
Dividend Paid [Member] |  |  |  |
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items] |  |  |  |
Dividends payable | $ 554,000 | $ 554,000 | $ 2,500,000 | $ 2,500,000

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