Commitments and Contingencies - Lease Supplemental Cash Flow Information, Term and Discount Rate (Details) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Commitments and Contingencies Disclosure [Abstract]
Operating lease costs	$ 5,216	$ 4,838
Variable lease costs	863	557
Cash paid for amounts included in the measurement of operating lease liabilities	$ 7,352	$ 5,108
Weighted average remaining lease term (in years)	15 years 4 months 24 days	2 years 10 months 24 days
Weighted average discount rate	3.40%	5.20%