Fair Value Measurements - Carrying Value and Estimated Fair Value of Financial Instruments (Details) - USD ($) $ in Millions	Sep. 30, 2021	Jun. 30, 2021
Carrying Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Broadcast rights payable	$ 22.9	$ 10.8
Total long-term debt	2,747.6	2,746.0
Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Broadcast rights payable	21.6	9.8
Total long-term debt	$ 2,850.4	$ 2,859.3