License agreements and acquired product rights - Total Purchase Price Allocated To Acquired Asset Based On Relative Estimated Fair Values (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Intangible assets	$ 58,576	$ 60,356
Shiongi License And Supply Agreement
Intangible assets	30,636
Symproic License | Shiongi License And Supply Agreement
Intangible assets	30,000
Transaction Expense | Shiongi License And Supply Agreement
Intangible assets	$ 636