Common Stock and Stockholders' Equity - Schedule of Assumptions Used to Estimate Fair Value of Stock Options Granted and ESPP Shares to be Issued (Detail)	12 Months Ended
Mar. 31, 2022	Mar. 31, 2021	Mar. 31, 2020
ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (years)	6 months	6 months	6 months
Dividend yield	0.00%	0.00%	0.00%
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (years)	0 years	6 years	6 years
Dividend yield	0.00%	0.00%	0.00%
Minimum \| ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility	38.00%	55.00%	33.00%
Risk-free interest rate	0.05%	0.06%	1.56%
Minimum \| Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility	0.00%	44.00%	41.00%
Risk-free interest rate	0.00%	0.34%	1.45%
Maximum \| ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility	76.00%	76.00%	60.00%
Risk-free interest rate	0.72%	0.12%	1.86%
Maximum \| Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility	0.00%	46.00%	42.00%
Risk-free interest rate	0.00%	0.76%	3.06%

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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- Definition

The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

+ References

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(i)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.D.2)
-URI http://asc.fasb.org/extlink&oid=122041274&loc=d3e301413-122809

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