Stock-Based Compensation - Assumptions Used to Determine Fair Values of Stock Option Grants (Detail) - USD ($)	12 Months Ended
Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2014
Graded Vesting [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate	1.40%	1.80%	2.10%
Dividend yield	2.30%	2.10%	2.30%
Weighted-average volatility factor	26.70%	24.20%	26.40%
Weighted-average expected life (in years)	6 years 6 months	6 years 10 months 18 days	6 years 10 months 18 days
Weighted-average fair value (in dollars)	$ 10.82	$ 10.21	$ 8.19
Cliff Vesting [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate	0.00%	0.00%	2.30%
Dividend yield	0.00%	0.00%	2.30%
Weighted-average volatility factor	0.00%	0.00%	26.40%
Weighted-average expected life (in years)	0 years	0 years	7 years 8 months 12 days
Weighted-average fair value (in dollars)	$ 0.00	$ 0.00	$ 8.76

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

+ References

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

No definition available.

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-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=6415400&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-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=27013229&loc=d3e301413-122809

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