IPR&D and Goodwill Intangible Assets and Goodwill - Additional Information (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2020	Dec. 31, 2019
Acquired Indefinite-lived Intangible Assets [Line Items]
In-process research and development	$ 17,628,000	$ 17,628,000
Goodwill impairment loss	0
IPR&D
Acquired Indefinite-lived Intangible Assets [Line Items]
In-process research and development	17,628,000	$ 17,628,000
Impairment of intangible assets	$ 0