Acquisitions - Additional Information (Detail) - USD ($)		3 Months Ended	9 Months Ended
	Jul. 12, 2019	Sep. 30, 2019	Sep. 30, 2019
Business Acquisition [Line Items]
Estimated contingent consideration		$ 2,750,000	$ 2,750,000
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	4,337,574	4,337,574
Number of consecutive trading days	20 days
Upfront consideration release at 6 months	33.30%
Upfront consideration release at 12 months	33.30%
Upfront consideration release at 18 months	33.30%
Stock price	$ 2.45
Estimated discount for lack of marketability	$ 832,277
Transaction cost recorded within research and development expense		61,673	680,090
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
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
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 6 months	50.00%
Upfront consideration release at 3 months	50.00%
Spitfire Pharma, Inc. [Member] | Regulatory Milestones [Member] | Monte Carlo Simulation [Member]
Business Acquisition [Line Items]
Estimated contingent consideration		$ 2,750,000	$ 2,750,000
Spitfire Pharma, Inc. [Member] | Maximum [Member]
Business Acquisition [Line Items]
Future contingent payments	$ 88,000,000