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The number of shares converted in a noncash (or part noncash) transaction. Noncash is defined as transactions during a period that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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Per share or per unit amount of equity securities issued.

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Equity - September 2018 issuance and exchange (Details) - USD ($) $ / shares in Units, $ in Millions		12 Months Ended
	Sep. 20, 2018	Dec. 31, 2018	Sep. 23, 2019
Conversion of series D preferred stock into common stock \| Series D convertible preferred stock
Conversion of stock
Shares converted	1,491	5,500
September 2018 public offering
Equity
Net proceeds from issuance of stock	$ 0.4
Common Stock \| Conversion of series D preferred stock into common stock
Conversion of stock
Shares issued on conversion	237	903
Common Stock \| September 2018 public offering
Equity
Stock issued (in shares)	696	696
Purchase price (in dollars per share)	$ 756.00
Warrants
Equity
Number of shares in exchange of warrant exercise	119
Warrant exercise price (in dollars per share)	$ 756.00
Warrants \| Placement agent warrants
Equity
Warrant exercise price (in dollars per share)			$ 6.00
Warrants \| September 2018 public offering
Equity
Number of shares in exchange of warrant exercise	348
Warrant exercise price (in dollars per share)	$ 756.00
Warrants \| September 2018 public offering \| Placement agent warrants
Equity
Number of shares in exchange of warrant exercise	49
Warrant exercise price (in dollars per share)	$ 945.00