Amount of potential milestone payment as a result of FDA approval.

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The increase (decrease) in a financial instrument as a result of an decrease in a designated risk component that was reasonably possible at the end of the reporting period. Excludes defined benefit plan obligations.

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No definition available.

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The increase (decrease) in a financial instrument as a result of an increase in a designated risk component that was reasonably possible at the end of the reporting period. Excludes defined benefit plan obligations.

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No definition available.

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- Definition

Amount of increase in estimated fair value of exit fee.

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The reasonably possible percentage of the decrease in the designated risk component used to determine the value of the financial instrument. Excludes defined benefit plan obligations.

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No definition available.

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The reasonably possible percentage of the increase in the designated risk component used to determine the value of the financial instrument. Excludes defined benefit plan obligations.

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No definition available.

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Includes, but is not limited to, one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, and relocating employees, and termination benefits associated with an ongoing benefit arrangement. Excludes expenses associated with special or contractual termination benefits, a discontinued operation or an asset retirement obligation.

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-Name Accounting Standards Codification
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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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No definition available.

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- Definition

Fair value of financial and nonfinancial obligations.

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Fair Value Measurements - Loan and Security Agreement (Details) - Solar Capital and Western Alliance Bank Loan Agreement [Member] - USD ($)	1 Months Ended	3 Months Ended
	May 31, 2018	Mar. 31, 2019	Dec. 31, 2018
Fair Value Measurements
Exit Fee	$ 1,500,000
Level 3 [Member]
Fair Value Measurements
Potential payment to Solar Capital Ltd. and Western Alliance Bank		$ 1,500,000
Percentage of increase in risk component		10.00%
Percentage decrease in risk component		10.00%
Fair value fluctuation due to increase in risk component		$ 100,000
Fair value fluctuation due to decrease in risk component		100,000
Derivative Liability Exit Fee [Member] \| Accrued and other liabilities
Fair Value Measurements
Estimated fair value of Exit Fee		570,000	$ 533,000
Increase in estimated fair value of exit fee		$ 37,000