Significant Accounting Policies - Accrued Expenses and Other Payables (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Mar. 31, 2020
Accounting Policies [Abstract]
Accrued compensation and benefits	$ 27,579	$ 29,990
Excise and other tax liabilities	10,273	9,941
Derivative liabilities	679	17,777
Accrued interest	23,126	39,803
Product exchange liabilities	4,972	1,687
Contingent consideration liability (1)	2,419	102,419
Other	33,721	30,445
Total	$ 102,769	$ 232,062