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Performance grant attainment percentage.

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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 Outstanding, Number

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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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- Definition

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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- Definition

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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- Definition

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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- Definition

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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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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-Name Accounting Standards Codification
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-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.D.2)
-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

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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 Millions		1 Months Ended					12 Months Ended
	Oct. 10, 2003	Jul. 31, 2015	Jul. 31, 2012	Jun. 30, 2012	Jul. 31, 2011	Oct. 31, 2010	May 31, 2017	May 31, 2016	May 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate intrinsic value of options outstanding							$ 47.2
Weighted-average remaining contractual life of options outstanding							6 years 9 months 18 days
Aggregate intrinsic value of options exercisable							$ 36.9
Weighted-average remaining contractual life of options exercisable							5 years 7 months 6 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							$ 25.5
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							$ 1.5
Shares granted to Directors							$ 50.61	$ 43.71	$ 43.89
Shares granted							24,000
Shares of common stock available for grant	500,000						77,350
Shares of restricted stock vested							40,000
2007 Plan and 2014 Omnibus Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted to Directors							$ 50.99	$ 46.63	$ 44.60
Shares granted							48,041
Shares outstanding							802,000	793,000
Employee Incentive Plan 2007
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unamortized stock-based compensation expense							$ 4.9
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							7 years	7 years	7 years 6 months
Unamortized stock-based compensation expense							$ 10.1
Unamortized stock-based compensation expense expected recognition period							3 years 3 months
Shares expected to vest							1,400,000
Shares expected to vest, weighted-average exercise price							$ 47.06
Shares expected to vest, weighted-average remaining contractual term							8 years 2 months 12 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							3,055,000
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
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation arrangement vesting period							3 years
Unamortized stock-based compensation expense							$ 27.1
Shares granted to Directors							$ 50.84	$ 45.79	$ 44.28
Shares granted							486,000
Shares of restricted stock vested							476,000
Performance Earned Restricted Stock Awards \| 2004 Omnibus Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unamortized stock-based compensation expense							$ 1.6
Performance Earned Restricted Stock Awards \| 2014 Omnibus Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unamortized stock-based compensation expense							25.5
Performance Contingent Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted to Directors			$ 25.87	$ 25.76	$ 22.16	$ 20.73
Shares granted			50,000	10,000	115,000	680,000
Performance Contingent Restricted Stock \| First Performance Segment
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance goals attainment period for PCRS awards						3 years
Performance Contingent Restricted Stock \| Second Performance Segment
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance goals attainment period for PCRS awards						5 years
2015 Performance Contingent Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unamortized stock-based compensation expense							$ 2.6
Shares granted to Directors		$ 46.87
Shares granted		329,000
Performance goals attainment period for PCRS awards		3 years
Shares outstanding							324,000
Performance grant attaining percentage							46.00%
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%
Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unamortized stock-based compensation expense							$ 0.5
Nonvested Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unamortized stock-based compensation expense							$ 37.7
Unamortized stock-based compensation expense expected recognition period							3 years 3 months 18 days
Shares granted to Directors							$ 50.84	$ 46.17	$ 44.29
Shares granted							558,000
Remaining weighted-average contractual term							3 years 3 months 18 days
Total fair value of shares vested							$ 20.3	$ 34.2	$ 14.7
Shares expected to vest							1,900,000
Shares expected to vest, weighted-average grant-date fair value							$ 43.32
Shares of restricted stock vested							602,000
Total intrinsic value of restricted shares converted							$ 9.0	$ 32.3	$ 13.9
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of restricted stock vested							263,857	310,238