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Collaboration and License Agreements (Details) - USD ($)	1 Months Ended	3 Months Ended		6 Months Ended
	Apr. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Collaborative Arrangements and Non-collaborative Arrangement Transactions
Alliance revenue			$ 1,448,000		$ 1,448,000
Operating expenses		$ 8,011,000	$ 12,964,000	$ 21,163,000	$ 24,340,000
Option and License Agreement with Licensee
Collaborative Arrangements and Non-collaborative Arrangement Transactions
Performance obligation		0		$ 0
Percentage of shares acquired				10.00%
Option and License Agreement with Licensee \| Other Assets
Collaborative Arrangements and Non-collaborative Arrangement Transactions
Value of securities without a readily determinable fair value		$ 100,000		$ 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%