Revenue Recognition - Additional Information (Details) - USD ($) $ in Thousands			12 Months Ended
	Apr. 29, 2019	Apr. 05, 2019	Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Deferred revenues			$ 65,000	$ 0
Everest Medicines II Limited
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Upfront fees paid	$ 65,000
Payment upon achievement of FDA approval	60,000
Development total payments	180,000
Sales total payments	530,000
Deferred revenues	$ 65,000
Janssen Biotech Inc
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Sales total payments		$ 15,000
Revenues			$ 300
Minimum | Everest Medicines II Limited
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Royalty payments percentage	14.00%
Maximum | Everest Medicines II Limited
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Royalty payments percentage	20.00%