Contingent Consideration - Additional Information (Detail) - USD ($)			3 Months Ended	9 Months Ended
	Nov. 03, 2020	Jul. 12, 2019	Sep. 30, 2020	Sep. 30, 2020	Dec. 31, 2019
Business Acquisition [Line Items]
Estimated future contingent consideration			$ 25,070,000	$ 25,070,000	$ 2,750,000
Change in value of contingent consideration for acquired in-process research and development				22,320,000
Subsequent Event [Member] | Clinical Trial Notification [Member]
Business Acquisition [Line Items]
Shares issued for contingent milestone payment	1,694,916
Period for submission of clinical trial notification	60 days
Submission date of clinical trial notification	Oct. 29, 2020
Percentage of shares released from restriction at 3 month	50.00%
Percentage of shares released from restriction at 6 month	50.00%
Spitfire Pharma, Inc. [Member]
Business Acquisition [Line Items]
Agreement date		Jul. 08, 2019
Unregistered shares of common stock		1,887,250
Up-front consideration		$ 5,000,000
Transaction cost recorded within research and development expense			100,000	700,000
Spitfire Pharma, Inc. [Member] | Investigational New Drug Application Milestone [Member]
Business Acquisition [Line Items]
Future contingent payments		$ 5,000,000
Future contingent payment term		60 days
Number of consecutive trading days		20 days
Consideration amount		$ 2.95
Spitfire Pharma, Inc. [Member] | Investigational New Drug Application and Regulatory Milestones [Member]
Business Acquisition [Line Items]
Future contingent payments		$ 3,000,000
Future contingent payment term		60 days
Number of consecutive trading days		20 days
Consideration amount		$ 3.54
Spitfire Pharma, Inc. [Member] | Sales Milestones [Member]
Business Acquisition [Line Items]
Future contingent payments		$ 80,000,000
License agreement term		10 years
Spitfire Pharma, Inc. [Member] | Regulatory Milestones [Member]
Business Acquisition [Line Items]
Upfront consideration release at 3 months		50.00%
Upfront consideration release at 9 months		50.00%
Spitfire Pharma, Inc. [Member] | Regulatory Milestones [Member] | Monte Carlo Simulation [Member]
Business Acquisition [Line Items]
Estimated future contingent consideration		$ 2,800,000	25,100,000	25,100,000
Change in value of contingent consideration for acquired in-process research and development			$ 8,700,000	$ 22,300,000
Spitfire Pharma, Inc. [Member] | Common Stock [Member] | Maximum [Member]
Business Acquisition [Line Items]
Future contingent payments		$ 88,000,000