Fair Value of Financial Instruments - Summary of Financial Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Millions	Jun. 30, 2020	Jun. 30, 2019
Cash and cash equivalents:
Money market funds	$ 150.1	$ 68.1
Other current assets:
Securities	0.5	0.4
Other non-current assets:
Securities	102.0	81.8
Level 1
Cash and cash equivalents:
Money market funds	150.1	68.1
Other current assets:
Securities	0.5	0.4
Other non-current assets:
Securities	102.0	81.8
Liabilities:
Contingent consideration obligations	0.0	0.0
Level 2
Cash and cash equivalents:
Money market funds	0.0	0.0
Other current assets:
Securities	0.0	0.0
Other non-current assets:
Securities	0.0	0.0
Liabilities:
Contingent consideration obligations	0.0	0.0
Level 3
Cash and cash equivalents:
Money market funds	0.0	0.0
Other current assets:
Securities	0.0	0.0
Other non-current assets:
Securities	0.0	0.0
Liabilities:
Contingent consideration obligations	33.1	28.4
Fair Value, Measurements, Recurring
Other non-current assets:
Total	252.7	150.3
Fair Value, Measurements, Recurring | Level 1
Other non-current assets:
Total	252.7	150.3
Liabilities:
Total	0.0	0.0
Fair Value, Measurements, Recurring | Level 2
Other non-current assets:
Total	0.0	0.0
Liabilities:
Total	0.0	0.0
Fair Value, Measurements, Recurring | Level 3
Other non-current assets:
Total	$ 0.0	$ 0.0