Certain Balance Sheet Components - Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Mar. 31, 2021
Other Liabilities Disclosure [Abstract]
Accrued R&D expenses	$ 7,894	$ 8,544
Accrued compensation-related expenses	17,936	20,571
Accrued commercial expenses	8,065	7,770
Accrued sales discounts, rebates, and allowances	4,737	1,315
Deferred net product revenue	0	162
Accrued professional service fees	1,075	935
Accrued other expenses and tax obligations	3,231	5,315
Total accrued expenses and other current liabilities	$ 42,938	$ 44,612