Leases - Lease Costs (Details) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Leases [Abstract]
Operating lease costs	$ 16,792	$ 20,846	$ 21,829
Variable and short-term lease costs	6,710
Total lease costs	$ 23,502