The amount represents the shares sold and not settled at the quarter end.

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Maximum Value of Common stock authorized to be issued under shelf registration statement

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The value of remaining unissued capital.

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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The cash outflow for cost incurred directly with the issuance of an equity security.

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The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

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The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

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Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

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Number of new stock issued during the period.

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Equity impact of the value of new stock issued during the period. Includes shares issued in an initial public offering or a secondary public offering.

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Ratio applied to the conversion of stock split, for example but not limited to, one share converted to two or two shares converted to one.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Stockholders' Deficit (Details) $ / shares in Units, $ in Thousands		1 Months Ended		3 Months Ended			9 Months Ended		12 Months Ended
	May 10, 2019 shares	Nov. 01, 2019 USD ($) shares	Apr. 30, 2018 USD ($) $ / shares shares	Sep. 30, 2019 USD ($) $ / shares shares	Mar. 31, 2019 USD ($) $ / shares shares	Mar. 31, 2018 USD ($) $ / shares shares	Sep. 30, 2019 USD ($) $ / shares shares	Sep. 30, 2018 USD ($)	Dec. 31, 2017 USD ($)	May 09, 2019 shares	Dec. 31, 2018 USD ($) shares	Jan. 31, 2017 USD ($)
Subsidiary, Sale of Stock [Line Items]
Reverse stock split	20
Common stock, shares authorized \| shares	600,000,000			600,000,000			600,000,000				600,000,000
Preferred stock, shares authorized \| shares	2,000,000			2,000,000			2,000,000				2,000,000
Common stock, shares outstanding \| shares	23,472,574			25,528,642			25,528,642			469,453,883	19,222,410
Proceeds from shares sold				$ 12,588			$ 67,830	$ 96,486
December 2018 Sales Agreement [Member]
Subsidiary, Sale of Stock [Line Items]
Sales per share price range \| $ / shares				$ 8.39			$ 8.39
Shares sold \| shares		1,000,000			1,700,000		3,600,000
Proceeds from shares sold		$ 5,000					$ 29,300
Proceeds from shares sold and not settled at quarter-end							$ 600
Shelf Registration Statement, Maximum Authorized Common Stock Issuance, Value											$ 100,000
Shelf Registration Statement Remaining Unissued Capital		$ 64,400
Public Offering [Member]
Subsidiary, Sale of Stock [Line Items]
Sales per share price range \| $ / shares			$ 33.00
Shares sold \| shares			1,700,000
Common stock issued upon exercise in full over-allotment granted \| shares			200,000
Payments of Stock Issuance Costs			$ 54,000
December 2017 Sales Agreement [Member]
Subsidiary, Sale of Stock [Line Items]
Sales per share price range \| $ / shares					$ 15.33	$ 41.86
Shares sold \| shares					2,500,000	800,000
Proceeds from shares sold					$ 37,900	$ 32,300			$ 75,000
January 2017 Sales Agreement [Member]
Subsidiary, Sale of Stock [Line Items]
Sales per share price range \| $ / shares						$ 30.80
Shares sold \| shares						300,000
Proceeds from shares sold						$ 10,300
Shelf Registration Statement, Maximum Authorized Common Stock Issuance, Value												$ 75,000