Employee Stock Purchase Plan - Additional Information (Detail) - shares	12 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Employee Stock Purchase Plan [Line Items]
Percentage of employees contribution of their gross pay	20.00%
Stock issued under employee stock purchase plan, shares	2,486,565
Employee Stock Purchase Plan [Member]
Employee Stock Purchase Plan [Line Items]
Percentage as purchase price of closing sale price of shares	95.00%
Maximum shares authorized for issuance under the ESPP	2,850,000
Stock issued under employee stock purchase plan, shares	8,451	8,271	8,976

Employee stock purchase plan employee contribution percent of gross pay.

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- Definition

Employee stock purchase plan.

+ References

No definition available.

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- Definition

Number of shares authorized for issuance under share-based payment arrangement.

+ 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 (a)(3)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

Purchase price of common stock expressed as a percentage of its fair value.

+ References

No definition available.

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- Definition

Number of shares issued during the period as a result of an employee stock purchase plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
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