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- Definition

Cash received from exercise of stock options

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of cost to be recognized for option under share-based payment arrangement.

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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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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.

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Percentage of vesting of award under share-based payment arrangement.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Stock Options and Stock-Based Compensation - Additional Information (Detail) - USD ($)	12 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Mar. 31, 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Non-statutory stock options expiration period	5 years
Weighted-average grant-date fair value of options granted	$ 75.49	$ 56.34	$ 50.29
Total intrinsic value of options exercised	$ 29,230,000	$ 21,094,000	$ 27,615,000
Weighted average period to recognized compensation cost	3 years
Time Based Options and Performance Based Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 4,982,000	5,559,000	5,198,000
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	1,199,000	1,961,000	2,280,000
Cash received from excercise of stock options	9,266,000	$ 10,856,000	$ 9,906,000
Unrecognized compensation costs related to stock options	$ 8,178,000
Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Non-statutory stock options expiration period	10 years
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock grants	20,615,000
Non-statutory stock options vesting period	36 months
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Non-statutory stock options vesting period	1 year
Share-based Compensation Award, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting Percentage	25.00%
Share-based Compensation Award, Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting Percentage	75.00%