Development, Commercialization and Supply Agreement - Changes in Balances of Contract Assets and Liabilities (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Contract liabilities:
Deferred revenue, Balance at Beginning of Period	$ 18,632	$ 20,846
Deferred revenue, Additions		3,750
Deferred revenue, Deductions	(662)	(2,789)
Deferred revenue, Balance at End of Period	$ 17,970	$ 21,807