Stock Options and Stock-Based Compensation - Stock Options Outstanding and Exercisable (Detail) - $ / shares	12 Months Ended
Mar. 31, 2026	Mar. 31, 2025
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number of Outstanding Options	1,196,283	1,185,727
Weighted Average Remaining Contractual Life	3 years 1 month 9 days
Outstanding Options – Weighted Average Exercise Price	$ 59.83	$ 51.07
Exercisable Options – Number of Exercisable Options	672,960
Exercisable Options – Weighted Average Exercise Price	$ 51.52
Range of Exercise Price, $14.44 to $51.01 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Price, lower limit	14.44
Range of Exercise Price, upper limit	$ 51.01
Number of Outstanding Options	303,116
Weighted Average Remaining Contractual Life	2 years 1 month 2 days
Outstanding Options – Weighted Average Exercise Price	$ 35.75
Exercisable Options – Number of Exercisable Options	298,373
Exercisable Options – Weighted Average Exercise Price	$ 35.53
Range of Exercise Price, $51.02 to $53.08 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Price, lower limit	51.02
Range of Exercise Price, upper limit	$ 53.08
Number of Outstanding Options	329,370
Weighted Average Remaining Contractual Life	3 years 8 months 4 days
Outstanding Options – Weighted Average Exercise Price	$ 52.73
Exercisable Options – Number of Exercisable Options	104,890
Exercisable Options – Weighted Average Exercise Price	$ 52.1
Range of Exercise Price, $53.09 to $74.09 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Price, lower limit	53.09
Range of Exercise Price, upper limit	$ 74.09
Number of Outstanding Options	325,404
Weighted Average Remaining Contractual Life	2 years 5 months 4 days
Outstanding Options – Weighted Average Exercise Price	$ 64.56
Exercisable Options – Number of Exercisable Options	231,802
Exercisable Options – Weighted Average Exercise Price	$ 63.99
Range of Exercise Price, $74.10 to $110.18 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Price, lower limit	74.1
Range of Exercise Price, upper limit	$ 110.18
Number of Outstanding Options	238,393
Weighted Average Remaining Contractual Life	4 years 6 months 10 days
Outstanding Options – Weighted Average Exercise Price	$ 93.78
Exercisable Options – Number of Exercisable Options	37,895
Exercisable Options – Weighted Average Exercise Price	$ 99.48

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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- Definition

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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- Definition

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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- Definition

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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- Definition

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.

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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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