Long-Term Debt and Credit Agreements - Long-Term Debt Maturities (Details) - USD ($) $ in Millions |
Jun. 30, 2017 |
Jun. 30, 2016 |
|---|---|---|
| Debt Disclosure [Abstract] | ||
| 2018 | $ 0.0 | |
| 2019 | 0.0 | |
| 2020 | 0.0 | |
| 2021 | 0.0 | |
| 2022 | 626.6 | |
| 2023 and thereafter | 125.0 | |
| Total long-term debt, net of debt issuance costs | $ 751.6 | $ 1,071.6 |