Stock-Based Compensation - Assumptions Used to Determine Fair Values of Stock Option Grants (Detail) - USD ($) |
12 Months Ended | ||
|---|---|---|---|
Jun. 30, 2015 |
Jun. 30, 2014 |
Jun. 30, 2013 |
|
| Graded Vesting [Member] | |||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||
| Risk-free interest rate | 1.80% | 2.10% | 1.30% |
| Dividend yield | 2.10% | 2.30% | 3.20% |
| Weighted-average volatility factor | 24.20% | 26.40% | 25.70% |
| Weighted-average expected life (in years) | 6 years 10 months 18 days | 6 years 10 months 18 days | 6 years 9 months 18 days |
| Weighted-average fair value (in dollars) | $ 10.21 | $ 8.19 | $ 3.78 |
| Cliff Vesting [Member] | |||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||
| Risk-free interest rate | 0.00% | 2.30% | 0.00% |
| Dividend yield | 0.00% | 2.30% | 0.00% |
| Weighted-average volatility factor | 0.00% | 26.40% | 0.00% |
| Weighted-average expected life (in years) | 7 years 8 months 18 days | ||
| Weighted-average fair value (in dollars) | $ 0.00 | $ 8.76 | $ 0.00 |