Amount of increase in additional paid in capital (APIC) resulting from reclassification of warrant liability to equity

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Milestone Payment To Be Paid By Company Upon Specified Development Milestone Achievement

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Milestone Payment To Be Paid By Company Upon Specified Development Milestone Achievement, Per Additional NDA Filing

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Number of directors to whom the Company agreed to issue warrants to purchase common shares.

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Exercise price per share or per unit of warrants or rights outstanding.

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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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Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of expense (income) related to adjustment to fair value of warrant liability.

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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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Value of outstanding derivative securities that permit the holder the right to purchase securities (usually equity) from the issuer at a specified price.

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Warrants - Narrative (Details) $ / shares in Units, $ in Thousands			1 Months Ended	3 Months Ended			6 Months Ended
	Jan. 26, 2018 USD ($)	Aug. 30, 2016 director	May 31, 2019 USD ($) $ / shares shares	Jun. 30, 2019 USD ($)	Jun. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Jun. 30, 2019 USD ($)	Jun. 30, 2018 USD ($)	Dec. 31, 2017 USD ($)
Warrants
Reclassification of fair value of warrant liability to shareholders' equity	$ 5,203					$ 5,203
Fair value of warrant liability									$ 4,021
Expense related to warrant liability				$ 0	$ 0		$ 0	$ 1,182
Value of common stock issued				$ 281,100	$ 43,842	$ 52,013
Credit Agreement \| Wells Fargo Term Loan
Warrants
Credit agreement term		1 year
Directors
Warrants
Number of directors to whom the Company agreed to issue warrants \| director		2
FCCDC Warrants
Warrants
Number of securities called by warrants (shares) \| shares			100,000
Exercise price of warrants (in dollars per share) \| $ / shares			$ 56.46
FCCDC Agreement \| Collaborative arrangement
Warrants
Common stock issued (shares) \| shares			100,000
Value of common stock issued			$ 5,646
Development milestone payment to be paid			4,500
Development milestone payments to be paid per each additional NDA filing			$ 1,000