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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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CO-DEVELOPMENT AND LICENSE AGREEMENT - Additional Information (Details) - Janssen - USD ($) $ in Millions			9 Months Ended
	Aug. 29, 2017	Feb. 13, 2014	Sep. 30, 2020
Collaborative Arrangement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Upfront payment received			$ 41.2
Seltorexant \| Collaborative Arrangement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Payment of license fee		$ 22.0
Upfront payment received			30.0
Previously accrued collaborative expenses recognized as revenue			$ 11.2
Seltorexant \| Amendment to Co-Development and License Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Upfront payment	$ 30.0