Stockholders' Equity - Stock-based Compensation Expense and Valuation Information - Additional Information (Detail) $ in Millions	3 Months Ended
Jun. 30, 2021 USD ($) Participant shares	Jun. 30, 2020 shares
Class Of Stock [Line Items]
Total unrecognized compensation cost related to unvested stock option grants	$ 3.7
Number of options granted \| shares	0	0
Expected term	6 months
Participants enrolled in the ESPP \| Participant	0
Stock options [Member]
Class Of Stock [Line Items]
Total unrecognized compensation cost related, weighted average period	2 years 7 months 13 days
RSUs [Member]
Class Of Stock [Line Items]
Total unrecognized compensation cost related, weighted average period	3 years 6 months 7 days
Unrecognized stock-based compensation expense	$ 0.2

Number of participants enrolled in employee stock purchase plan.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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Amount of cost to be recognized for option under share-based payment arrangement.

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Gross number of share options (or share units) granted during the period.

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Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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