Leases - Summary of Components of Lease Costs (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2020	Dec. 31, 2019
Lease cost
Operating lease cost	$ 64	$ 63	$ 191	$ 190
Finance lease cost	0	0	0	0
Amortization of right-of-use assets	0	0	0	0
Interest on lease liabilities	0	0	0	0
Variable lease costs	0	0	0	0
Total lease cost	64	63	191	190
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	67	66	200	197
Operating cash flows from finance leases	0	0	0	0
Financing cash flows from finance leases	0	0	0	1
Right-of-use assets obtained in exchange for lease obligations:
Operating leases	0	0	0	650
Finance leases	$ 0	$ 0	$ 0	$ 5