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Share Based Compensation Arrangement by Share Based Payment Awards Performance Period

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Aggregate number of common shares reserved for future issuance.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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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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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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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Weighted average remaining contractual term for equity-based awards excluding options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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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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Number of additional shares authorized for issuance under share-based payment arrangement.

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Number of shares authorized for issuance under share-based payment arrangement.

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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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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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

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Expected term of 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 difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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Stock-Based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions		1 Months Ended	12 Months Ended
	Oct. 10, 2003	Oct. 31, 2019	May 31, 2023	May 31, 2022	May 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate intrinsic value of options outstanding			$ 29.4
Weighted-average remaining contractual life of options outstanding			5 years 11 months 12 days
Aggregate intrinsic value of options exercisable			$ 27.8
Weighted-average remaining contractual life of options exercisable			4 years 7 months 24 days
Omnibus Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Incentive plan approval date			Oct. 09, 2014
2014 Omnibus Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock authorized			6,000,000
Additional shares of common stock authorized		5,000,000
Shares available for future issuance			0
Directors Equity Incentive Plan 2003
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Incentive plan approval date	Oct. 10, 2003
Share based compensation arrangement vesting period	3 years
Unamortized stock-based compensation expense			$ 2.3
Weighted-average grant date fair value			$ 92.87	$ 81.53	$ 87.35
Shares granted			21,000
Shares of common stock available for grant	500,000
Shares of restricted stock vested			25,000
2007 Plan and 2014 Omnibus Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average grant date fair value			$ 81.01	$ 86.93	$ 78.49
Shares granted			23,705
Shares outstanding			390,000	386,000
Employee Incentive Plan 2007
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unamortized stock-based compensation expense			$ 4.1
Shares granted			0
SARs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock appreciation rights expected term			6 years	6 years	6 years 6 months
Unamortized stock-based compensation expense			$ 9.3
Unamortized stock-based compensation expense expected recognition period			2 years 6 months 3 days
Shares expected to vest			2,300,000
Shares expected to vest, weighted-average exercise price			$ 68.17
Shares expected to vest, weighted-average remaining contractual term			5 years 11 months 8 days
SARs \| Omnibus Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock appreciation rights expected term			10 years
Share based compensation arrangement vesting period			4 years
Stock options outstanding			2,287,500
Full Value Stock Award \| 2014 Omnibus Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock authorized			3,000,000
Additional shares of common stock authorized		2,250,000
Performance Earned Restricted Stock Awards and Performance Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation arrangement vesting period			3 years
Unamortized stock-based compensation expense			$ 11.5
Weighted-average grant date fair value			$ 81.03	$ 86.88	$ 80.67
Shares granted			223,000
Shares of restricted stock vested			359,000
Performance Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance goals attainment period for PSUs awards			3 years
Performance Stock Units \| Earnings Before Interest Taxes Margin
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage			50.00%
Performance Stock Units \| Upon Achievement of Performance Goals \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage			0.00%
Performance Stock Units \| Upon Achievement of Performance Goals \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage			200.00%
Nonvested Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unamortized stock-based compensation expense			$ 27.5
Weighted-average grant date fair value			$ 81.95
Shares granted			268,000
Remaining weighted-average contractual term			2 years 1 month 17 days
Shares expected to vest			1,080,000.00
Shares of restricted stock vested			432,000