Stock-Based Compensation - Assumptions Used to Determine Fair Values of Stock Option Grants (Details) - USD ($) |
12 Months Ended | ||
|---|---|---|---|
Jun. 30, 2019 |
Jun. 30, 2018 |
Jun. 30, 2017 |
|
| Graded Vesting | |||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||
| Risk-free interest rate | 2.50% | 2.70% | 2.10% |
| Dividend yield | 2.00% | 1.60% | 2.00% |
| Weighted-average volatility factor | 26.00% | 23.80% | 23.10% |
| Weighted-average expected life (in years) | 5 years 10 months 24 days | 6 years 6 months | 6 years 6 months |
| Weighted-average fair value (in dollars) | $ 22.12 | $ 22.16 | $ 13.74 |
| 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 | ||