License Agreements (Details)	12 Months Ended
Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Aggregate cash payments received from license agreement	$ 70,000,000
AVP-825 License Agreement
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Licensing revenue	0	$ 0
Currax License Agreement
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Upfront payment received	3,730,000
Additional revenue eligible and held in escrow	$ 750,000
Royalty Agreement Terms
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Percentage of royalty	0.10
Development milestone payments eligible to be received (up to)	$ 3,000,000
Sales milestone payments eligible to be received (up to)	1,000,000
Inexia License Agreement
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Upfront payment received	500,000
Development milestone payments eligible to be received (up to)	8,000,000
Sales milestone payments eligible to be received (up to)	$ 37,000,000

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- Definition

Percentage Of Royalty

+ References

No definition available.

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- Definition

Research and Development Arrangement, Contract to Perform for Others, Additional Revenue Eligible And Held In Escrow

+ References

No definition available.

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- Definition

Research And Development Arrangement, Contract To Perform For Others, Milestone Payments, Maximum Eligible

+ References

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- Definition

Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130549-203045

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- Definition

Cash received from licensees for license fees during the current period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3536-108585

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- Definition

The amount of compensation earned (contract income) under a research and development arrangement accounted for as a contract to perform research and development for others.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 730
-SubTopic 20
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6420387&loc=d3e23221-108380

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-Section 50
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=6420387&loc=d3e23199-108380

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- Definition

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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