Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($)	3 Months Ended		9 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2022	Dec. 31, 2021	Mar. 31, 2022
Summary Of Significant Accounting Policies [Line Items]
Cash and cash equivalents	$ 20,196,000	$ 30,269,000	$ 20,196,000	$ 30,269,000	$ 28,675,000
Restricted cash	143,000	143,000	143,000	143,000	143,000
Accumulated deficit	$ (317,539,000)		(317,539,000)		$ (307,739,000)
Cash flow from operations			$ 7,675,000	6,912,000
Issuance of common stock	8,714,590		8,714,590		8,710,627
Dilutive effect	$ 0	$ 0	$ 0	$ 0
Common stock equivalents excluded from computing diluted net loss per share			1,500,000	1,100,000
At-The-Market Facility [Member]
Summary Of Significant Accounting Policies [Line Items]
Issuance of common stock	0		0