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Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Expected to Vest, Number

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Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Expected to Vest, Weighted Average Grant Date Fair Value

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Share Based Compensation Arrangement By Share Based Payment Award Options Expected To Vest Weighted Average Exercise Price

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Share Based Compensation Arrangement By Share Based Payment Award Options Expected To Vest Weighted Average Remaining Contractual Term

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Share Based Compensation Arrangement by Share Based Payment Awards Performance Period

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Unrecognized cost of unvested share-based compensation awards.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, 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 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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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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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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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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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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- Definition

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

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- Definition

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Percentage of vesting of share-based compensation awards.

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Intrinsic value of equity-based compensation awards outstanding. Excludes stock and unit options.

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Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the 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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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for option awards outstanding, 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 - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands			1 Months Ended	12 Months Ended
	Oct. 03, 2018	Oct. 10, 2003	Jul. 31, 2015	May 31, 2019	May 31, 2018	May 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate intrinsic value of options outstanding				$ 25,900
Weighted-average remaining contractual life of options outstanding				5 years 7 months 28 days
Aggregate intrinsic value of options exercisable				$ 24,900
Weighted-average remaining contractual life of options exercisable				4 years 4 months 24 days
Omnibus Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Incentive plan approval date				Oct. 09, 2014
2004 Omnibus Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock authorized				12,000,000
2014 Omnibus Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unamortized stock-based compensation expense				$ 2,100
Shares of common stock authorized				6,000,000
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				$ 1,400
Shares granted to Directors				$ 60.50	$ 51.63	$ 50.61
Shares granted				23,000
Shares of common stock available for grant		500,000		30,300
Shares of restricted stock vested				35,000
2007 Plan and 2014 Omnibus Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted to Directors				$ 60.01	$ 55.19	$ 50.99
Shares granted				38,946
Shares outstanding				432,000	702,000
Employee Incentive Plan 2007
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unamortized stock-based compensation expense				$ 1,200
Shares of common stock available for grant				0
SARs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock appreciation rights expected term				6 years 6 months	7 years	7 years
Unamortized stock-based compensation expense				$ 8,600
Unamortized stock-based compensation expense expected recognition period				2 years 6 months 7 days
Shares expected to vest				3,100,000
Shares expected to vest, weighted-average exercise price				$ 46.38
Shares expected to vest, weighted-average remaining contractual term				5 years 7 months 6 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				3,097,500
Full Value Stock Award \| 2004 Omnibus Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock authorized				6,000,000
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
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				$ 11,700
Shares granted to Directors				$ 60.36	$ 52.26	$ 50.84
Shares granted				440,000
Shares of restricted stock vested				624,000
2015 Performance Contingent Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted to Directors			$ 46.87
Shares granted			329,000
Performance goals attainment period for PCRS awards			3 years
Shares outstanding					301,000
2015 Performance Contingent Restricted Stock \| Earnings Before Interest Taxes
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage			67.00%
2015 Performance Contingent Restricted Stock \| Earnings Before Interest Taxes Margin
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage			33.00%
2018 Contingent Performance Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unamortized stock-based compensation expense				$ 5,600
Unamortized stock-based compensation expense expected recognition period				2 years
Shares granted to Directors	$ 60.50
Shares granted	192,000
Performance goals attainment period for PCRS awards	3 years
Shares outstanding				166,000
2018 Contingent Performance Stock Units \| Earnings Before Interest Taxes
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	50.00%
2018 Contingent Performance Stock Units \| Earnings Before Interest Taxes Margin
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	50.00%
2018 Contingent Performance Stock Units \| Upon Achievement of Performance Goals \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	0.00%
2018 Contingent Performance Stock Units \| Upon Achievement of Performance Goals \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	200.00%
Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unamortized stock-based compensation expense				$ 70
Nonvested Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unamortized stock-based compensation expense				$ 24,700
Unamortized stock-based compensation expense expected recognition period				2 years 2 months 26 days
Shares granted to Directors				$ 60.34	$ 52.62	$ 50.84
Shares granted				503,000
Remaining weighted-average contractual term				2 years 2 months 26 days
Total fair value of shares vested				$ 37,800	$ 29,900	$ 20,300
Shares expected to vest				1,090,000
Shares expected to vest, weighted-average grant-date fair value				$ 52.35
Shares of restricted stock vested				833,000
Total intrinsic value of restricted shares converted				$ 58,100	$ 7,600	$ 9,000
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of restricted stock vested				832,717	360,762