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.

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

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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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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.

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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.

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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.

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Stock-Based Compensation and Stock Options - Stock Options Outstanding and Exercisable (Detail) - $ / shares	9 Months Ended
	Dec. 31, 2021	Sep. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Mar. 31, 2020
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number of Outstanding Options	796,858	778,982	937,158	1,033,436	975,917	1,029,103
Weighted Average Remaining Contractual Life	3 years 3 months 29 days
Outstanding Options – Weighted Average Exercise Price	$ 80.27	$ 72.17	$ 64.28	$ 62.30	$ 57.97	$ 54.87
Exercisable Options – Number of Exercisable Options	315,389
Exercisable Options – Weighted Average Exercise Price	$ 53.99
Range of Exercise Price, $22.07 to $52.69 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Price, lower limit	22.07
Range of Exercise Price, upper limit	$ 57.35
Number of Outstanding Options	232,852
Weighted Average Remaining Contractual Life	2 years 6 months 29 days
Outstanding Options – Weighted Average Exercise Price	$ 44.60
Exercisable Options – Number of Exercisable Options	192,721
Exercisable Options – Weighted Average Exercise Price	$ 42.75
Range of Exercise Price, $52.70 to $70.24 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Price, lower limit	57.36
Range of Exercise Price, upper limit	$ 77.93
Number of Outstanding Options	227,247
Weighted Average Remaining Contractual Life	2 years 3 months 7 days
Outstanding Options – Weighted Average Exercise Price	$ 68.91
Exercisable Options – Number of Exercisable Options	85,914
Exercisable Options – Weighted Average Exercise Price	$ 65.74
Range of Exercise Price, $70.25 to $87.69 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Price, lower limit	77.94
Range of Exercise Price, upper limit	$ 88.22
Number of Outstanding Options	205,159
Weighted Average Remaining Contractual Life	4 years 2 months 26 days
Outstanding Options – Weighted Average Exercise Price	$ 86.24
Exercisable Options – Number of Exercisable Options	36,754
Exercisable Options – Weighted Average Exercise Price	$ 85.51
Range of Exercise Price, $87.70 to $119.48 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Price, lower limit	88.23
Range of Exercise Price, upper limit	$ 197.16
Number of Outstanding Options	131,600
Weighted Average Remaining Contractual Life	5 years 21 days
Outstanding Options – Weighted Average Exercise Price	$ 153.70
Exercisable Options – Number of Exercisable Options	0
Exercisable Options – Weighted Average Exercise Price	$ 0