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Amount of investment in equity security without readily determinable fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=116654751&loc=SL75117539-209714

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-Name Accounting Standards Codification
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-Section 50
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Collaboration and License Agreements (Details) - USD ($)	1 Months Ended	3 Months Ended	12 Months Ended
	Apr. 30, 2019	Mar. 31, 2020	Dec. 31, 2019
Collaborative Arrangements and Non-collaborative Arrangement Transactions
Operating expenses		$ 13,152,000	$ 11,376,000
Option and License Agreement with Licensee
Collaborative Arrangements and Non-collaborative Arrangement Transactions
Performance obligation		$ 0
Percentage of shares acquired		10.00%
Option and License Agreement with Licensee \| Other Assets
Collaborative Arrangements and Non-collaborative Arrangement Transactions
Equity Securities without Readily Determinable Fair Value, Amount		$ 100,000
IMO-9200 License \| Up-front Payment Arrangement
Collaborative Arrangements and Non-collaborative Arrangement Transactions
Upfront payment received under collaboration agreement	$ 1,400,000
Non-refundable fee upon exercise of option	$ 1,000,000
IMO-9200 License \| Option and License Agreement with Licensee
Collaborative Arrangements and Non-collaborative Arrangement Transactions
Percentage of shares acquired	10.00%