Licenses, Asset Acquisitions and Contingent Consideration - Additional Information (Details) - USD ($)					1 Months Ended			3 Months Ended		6 Months Ended
	May 11, 2020	Sep. 21, 2018	Jun. 24, 2018	Oct. 02, 2017	May 31, 2019	Jun. 30, 2018	Oct. 31, 2017	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Business Acquisition [Line Items]
In process research and development						$ 20,000,000.0		$ 15,000	$ 15,000,000	$ 45,000	$ 17,805,000
GB004
Business Acquisition [Line Items]
In process research and development								0	$ 15,000,000	0	$ 15,000,000
Pulmokine, Inc. | License Agreement | Seralutinib
Business Acquisition [Line Items]
Product license term (in years)				10 years
Upfront payment							$ 5,500,000
Milestones accrued								0		0		$ 5,000,000.0
Pulmokine, Inc. | License Agreement | Seralutinib | Maximum
Business Acquisition [Line Items]
Development and regulatory milestone payments, payable				$ 63,000,000.0
Commercial milestone payments, payable				45,000,000.0
Sales milestone payments, payable				$ 190,000,000.0
Aerpio Pharmaceuticals, Inc. | License Agreement | GB004
Business Acquisition [Line Items]
Upfront payment	$ 15,000,000.0
Milestones accrued								0		0
Participation rights (as a percent)			20.00%
Aerpio Pharmaceuticals, Inc. | License Agreement | GB004 | Maximum
Business Acquisition [Line Items]
Development and regulatory milestone payments, payable	40,000,000.0
Sales milestone payments, payable	$ 50,000,000.0
Adhaere Pharmaceuticals, Inc. | GB1275
Business Acquisition [Line Items]
Milestones accrued								$ 0		$ 0
In process research and development		$ 7,500,000
Upfront payment, purchase consideration paid		7,500,000
Milestones payment					$ 1,000,000.0
Adhaere Pharmaceuticals, Inc. | GB1275 | Maximum
Business Acquisition [Line Items]
Regulatory, development and sales milestone payments payable		$ 62,000,000.0