Income Taxes - Loss Before Income Taxes and Related Tax Benefit (Details) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Mar. 31, 2020
(Loss) income before income taxes:
Bermuda	$ (8,415)	$ (12,310)	$ (19,054)
Loss before income taxes	(200,933)	(254,798)	(288,228)
Current taxes:
Bermuda	0	1	0
Total current tax expense	5,048	336	761
Deferred taxes:
Bermuda	0	0	0
Total deferred tax expense	0	0	0
Total income tax expense	5,048	336	761
United States
(Loss) income before income taxes:
Foreign	45,446	(40,663)	(29,509)
Current taxes:
Foreign	5,048	335	758
Deferred taxes:
Foreign	0	0	0
Switzerland
(Loss) income before income taxes:
Foreign	(237,903)	(201,673)	(239,666)
Current taxes:
Foreign	0	0	0
Deferred taxes:
Foreign	0	0	0
Other
(Loss) income before income taxes:
Foreign	(61)	(152)	1
Current taxes:
Foreign	0	0	3
Deferred taxes:
Foreign	$ 0	$ 0	$ 0