Stock-Based Compensation - Assumptions Used to Determine Fair Values of Stock Option Grants (Details) - USD ($)	12 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2018
Graded Vesting
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate	1.50%	2.50%	2.70%
Dividend yield	1.80%	2.00%	1.60%
Weighted-average volatility factor	23.00%	26.00%	23.80%
Weighted-average expected life (in years)	5 years 8 months 12 days	5 years 10 months 24 days	6 years 6 months
Weighted-average fair value (in dollars)	$ 21.49	$ 22.12	$ 22.16
Cliff Vesting
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate			2.70%
Dividend yield			1.60%
Weighted-average volatility factor			23.80%
Weighted-average expected life (in years)			6 years
Weighted-average fair value (in dollars)			$ 21.65

Share Based Compensation Arrangement by Share Based Payment Award Fair Value

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Dividend Rate Maximum

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No definition available.

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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

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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
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