Stockholders' Equity (Schedule of Assumptions for Fair Value of Stock Option Plans and Purchase Rights Granted) (Details) - $ / shares	12 Months Ended
Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2021
Stock options:
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant date fair value (in dollars per share)	$ 74.95	$ 72.16	$ 53.67
Weighted average risk-free interest rate	3.85%	1.29%	0.37%
Expected life in years	4 years 10 months 24 days	4 years 10 months 24 days	4 years 10 months 24 days
Dividend yield	0.78%	0.66%	0.75%
Expected volatility	34.00%	32.00%	31.00%
ESPP purchase rights:
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant date fair value (in dollars per share)	$ 52.38	$ 50.46	$ 48.18
Weighted average risk-free interest rate	3.60%	0.30%	0.10%
Expected life in years	6 months	6 months	6 months
Expected volatility, minimum	27.00%	20.00%	30.00%
Expected volatility, maximum	34.00%	34.00%	60.00%
ESPP purchase rights: \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dividend yield	0.75%	0.63%	0.79%
ESPP purchase rights: \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dividend yield	0.84%	0.98%	0.98%

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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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.

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The estimated measure of the maximum 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.

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The estimated measure of the minimum 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.

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

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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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- 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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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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