The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

+ References

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- Definition

Number of options outstanding, including both vested and non-vested options.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(ii)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

+ References

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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.

+ References

No definition available.

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The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (g)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ References

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- Definition

Weighted average remaining contractual term of outstanding stock options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 718
-SubTopic 10
-Subparagraph (e)(1)
-Name Accounting Standards Codification
-Paragraph 2
-Section 50
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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Stock Options and Stock-Based Compensation - Stock Options Outstanding and Exercisable (Detail) - $ / shares	12 Months Ended
	Mar. 31, 2025	Mar. 31, 2024	Mar. 31, 2023	Mar. 31, 2022
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number of Outstanding Options	1,185,727	1,469,181	1,955,571	2,171,628
Weighted Average Remaining Contractual Life	2 years 11 months 12 days
Outstanding Options – Weighted Average Exercise Price	$ 51.07	$ 43.13	$ 36.03
Exercisable Options – Number of Exercisable Options	740,454
Exercisable Options – Weighted Average Exercise Price	$ 39.87
Range of Exercise Price, $11.05 to $29.23 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Price, lower limit	11.05
Range of Exercise Price, upper limit	$ 29.23
Number of Outstanding Options	337,577
Weighted Average Remaining Contractual Life	2 years 1 month 20 days
Outstanding Options – Weighted Average Exercise Price	$ 22.42
Exercisable Options – Number of Exercisable Options	337,577
Exercisable Options – Weighted Average Exercise Price	$ 22.42
Range of Exercise Price, $29.24 to $52.00 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Price, lower limit	29.24
Range of Exercise Price, upper limit	$ 52
Number of Outstanding Options	358,978
Weighted Average Remaining Contractual Life	2 years 6 months 10 days
Outstanding Options – Weighted Average Exercise Price	$ 48.86
Exercisable Options – Number of Exercisable Options	219,751
Exercisable Options – Weighted Average Exercise Price	$ 47.56
Range of Exercise Price, $52.01 to $66.85 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Price, lower limit	52.01
Range of Exercise Price, upper limit	$ 66.85
Number of Outstanding Options	330,661
Weighted Average Remaining Contractual Life	3 years 2 months 23 days
Outstanding Options – Weighted Average Exercise Price	$ 62.32
Exercisable Options – Number of Exercisable Options	169,138
Exercisable Options – Weighted Average Exercise Price	$ 61.84
Range of Exercise Price, $66.86 to $110.18 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Price, lower limit	66.86
Range of Exercise Price, upper limit	$ 110.18
Number of Outstanding Options	158,511
Weighted Average Remaining Contractual Life	5 years 18 days
Outstanding Options – Weighted Average Exercise Price	$ 93.6
Exercisable Options – Number of Exercisable Options	13,988
Exercisable Options – Weighted Average Exercise Price	$ 74.2