Stock-Based Compensation (Summary Of Nonvested Shares) (Details) shares in Thousands	12 Months Ended
Apr. 30, 2020 $ / shares shares
Shares
Outstanding, beginning of the year (in shares) \| shares	1,583
Granted (in shares) \| shares	1,093
Released (in shares) \| shares	(424)
Forfeited (in shares) \| shares	(172)
Outstanding, end of the year (in shares) \| shares	2,080
Weighted-Average Grant Date Fair Value
Outstanding, beginning of the year (in usd per share) \| $ / shares	$ 24.34
Granted (in usd per share) \| $ / shares	28.50
Released (in usd per share) \| $ / shares	25.30
Forfeited (in usd per share) \| $ / shares	27.45
Outstanding, end of the year (in usd per share) \| $ / shares	$ 25.94
Nonvested Shares And Performance Nonvested
Shares
Outstanding, beginning of the year (in shares) \| shares	1,238
Granted (in shares) \| shares	483
Released (in shares) \| shares	(450)
Forfeited (in shares) \| shares	(26)
Outstanding, end of the year (in shares) \| shares	1,245
Weighted-Average Grant Date Fair Value
Outstanding, beginning of the year (in usd per share) \| $ / shares	$ 26.89
Granted (in usd per share) \| $ / shares	32.01
Released (in usd per share) \| $ / shares	25.36
Forfeited (in usd per share) \| $ / shares	30.09
Outstanding, end of the year (in usd per share) \| $ / shares	$ 29.12

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(3)
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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

+ References

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- Definition

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).

+ References

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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).

+ References

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

+ References

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-Publisher FASB
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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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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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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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