Stockholders' Equity (Schedule Of Assumptions For Fair Value Of Stock Option Plans And Purchase Rights Granted) (Details) - $ / shares	12 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility	25.00%	23.00%	23.00%
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant date fair value	$ 32.14	$ 21.92	$ 16.68
Weighted average risk-free interest rate	1.58%	2.96%	2.08%
Expected life in years	4 years 10 months 24 days	4 years 10 months 24 days	4 years 10 months 24 days
Dividend yield	1.07%
ESPP Purchase Rights [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant date fair value	$ 31.82	$ 22.12	$ 17.44
Weighted average risk-free interest rate	1.60%	2.40%	0.80%
Expected life in years	6 months	6 months	6 months
Expected volatility		23.00%	23.00%
Minimum [Member] \| Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dividend yield		1.34%	1.46%
Minimum [Member] \| ESPP Purchase Rights [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dividend yield	0.98%	1.40%	1.47%
Expected volatility	23.00%
Maximum [Member] \| Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dividend yield		1.46%	1.65%
Maximum [Member] \| ESPP Purchase Rights [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dividend yield	1.42%	1.47%	1.92%
Expected volatility	60.00%

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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- Definition

The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

+ References

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

+ References

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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.

+ References

No definition available.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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- Definition

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.

+ References

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 (f)(2)(i)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.D.2)
-URI http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809

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