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Payment related to royalties or clinical development and regulatory milestones received.

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Payments for clinical development and regulatory milestone.

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Percentage of maximum royalty based on achievement of annual net product sales thresholds.

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Percentage of royalty on net sales.

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Sales milestone payments receivable.

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The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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License Agreements - Additional Information (Details) - USD ($)	1 Months Ended	3 Months Ended	5 Months Ended	12 Months Ended
	Mar. 31, 2019	Mar. 31, 2020	Dec. 31, 2020	Dec. 31, 2020	Dec. 31, 2019
George Washington
Research And Development Arrangement Contract To Perform For Others [Line Items]
Milestone payment		$ 500,000
Percentage of royalty on net sales				6.00%
Percentage of payments from sublicensee				15.00%
Royalty payments				$ 1,700,000	$ 1,200,000
Harvard
Research And Development Arrangement Contract To Perform For Others [Line Items]
Percentage of royalty on net sales				5.00%
Percentage of payments from sublicensee				20.00%
Clinical development and regulatory milestones amount payable				$ 15,100,000
Percentage of minimum royalty rate				4.50%
Percentage of maximum royalty based on achievement of annual net product sales thresholds				7.50%
Royalties payment			$ 200,000
Payments related to clinical development and regulatory milestones			$ 0
Paratek
Research And Development Arrangement Contract To Perform For Others [Line Items]
Percentage of royalty on net sales	2.25%
Claim expiration			2023-10
Paratek \| Minimum
Research And Development Arrangement Contract To Perform For Others [Line Items]
Royalties payment			$ 100,000
Tetraphase and Everest Medicines Limited
Research And Development Arrangement Contract To Perform For Others [Line Items]
Future clinical development and regulatory milestone payments receivable			11,000,000.0	$ 11,000,000.0
Sales milestone payments receivable			20,000,000.0	$ 20,000,000.0
Royalties payable description				Royalties are payable with respect to each jurisdiction in the Everest Territory until the latest to occur of: (1) the last-to-expire of specified patent rights in such jurisdiction in the Everest Territory; (2) expiration of marketing or regulatory exclusivity in such jurisdiction in the Everest Territory; or (3) 10 years after the first commercial sale of a product in such jurisdiction in the Everest Territory.
Royalties payable period after first commercial sale of product				10 years
Payment received related to royalties or clinical development and regulatory milestones			$ 0