Represents the number of drug candidates in clinical development.

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- Definition

Sum of investments and unrestricted cash as of the balance sheet date.

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Amount of cash inflow (outflow) from operating activities, including discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities.

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Amount, after deduction of tax, noncontrolling interests, dividends on preferred stock and participating securities; of income (loss) available to common shareholders.

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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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Nature of Business and Overview - (Details) $ in Thousands		3 Months Ended								12 Months Ended
Nature of Business and Overview - (Details) $ in Thousands	Feb. 08, 2019	Dec. 31, 2018 USD ($)	Sep. 30, 2018 USD ($)	Jun. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Sep. 30, 2017 USD ($)	Jun. 30, 2017 USD ($)	Mar. 31, 2017 USD ($)	Dec. 31, 2018 USD ($) product	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Nature of Business and Overview
Number of drug candidates in clinical development \| product										4
Cash, cash equivalents and marketable securities		$ 94,000								$ 94,000
Net Loss		$ (9,402)	$ (7,243)	$ (16,407)	$ (118,132)	$ (3,841)	$ (26,363)	$ (28,566)	$ (34,261)	(151,184)	$ (93,031)	$ (128,530)
Net cash used in operations										$ 75,235	$ 99,931	$ 113,036
Reverse stock split	0.067