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.

+ Details

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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, 2024	Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2021
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number of Outstanding Options	489,727	651,857	723,876	937,158
Weighted Average Remaining Contractual Life	3 years 1 month 28 days
Outstanding Options – Weighted Average Exercise Price	$ 129.39	$ 108.1	$ 84.55
Exercisable Options – Number of Exercisable Options	269,253
Exercisable Options – Weighted Average Exercise Price	$ 96.87
Range of Exercise Price, $33.16 to $77.93 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Price, lower limit	33.16
Range of Exercise Price, upper limit	$ 87.49
Number of Outstanding Options	133,743
Weighted Average Remaining Contractual Life	2 years 6 months 18 days
Outstanding Options – Weighted Average Exercise Price	$ 62.8
Exercisable Options – Number of Exercisable Options	127,559
Exercisable Options – Weighted Average Exercise Price	$ 62.15
Range of Exercise Price, $77.94 to $103.31 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Price, lower limit	87.5
Range of Exercise Price, upper limit	$ 148.89
Number of Outstanding Options	127,254
Weighted Average Remaining Contractual Life	2 years 14 days
Outstanding Options – Weighted Average Exercise Price	$ 111.95
Exercisable Options – Number of Exercisable Options	89,078
Exercisable Options – Weighted Average Exercise Price	$ 103.1
Range of Exercise Price, $103.32 to $155.99 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Price, lower limit	189.03
Range of Exercise Price, upper limit	$ 235.34
Number of Outstanding Options	90,845
Weighted Average Remaining Contractual Life	4 years 7 days
Outstanding Options – Weighted Average Exercise Price	$ 203.48
Exercisable Options – Number of Exercisable Options	14,743
Exercisable Options – Weighted Average Exercise Price	$ 197.16
Range of Exercise Price, $156.00 to $197.16 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Price, lower limit	148.9
Range of Exercise Price, upper limit	$ 189.02
Number of Outstanding Options	137,885
Weighted Average Remaining Contractual Life	4 years 2 months 23 days
Outstanding Options – Weighted Average Exercise Price	$ 161.24
Exercisable Options – Number of Exercisable Options	37,873
Exercisable Options – Weighted Average Exercise Price	$ 160.12