Fair Value of Financial Instruments - Summary of Financial Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Millions		Dec. 31, 2016	Jun. 30, 2016
Cash and cash equivalents
Money market funds	[1]	$ 89.2	$ 121.0
Other current assets
Available-for-sale securities		0.1	0.1
Other non-current assets
Available-for-sale securities		45.6	35.5
Total assets as of period end		134.9	156.6
Liabilities
Contingent consideration obligations:		5.9	5.5
Total liabilities as of period end		5.9	5.5
Level 1
Cash and cash equivalents
Money market funds	[1]	89.2	121.0
Other current assets
Available-for-sale securities		0.1	0.1
Other non-current assets
Available-for-sale securities		44.5	34.4
Total assets as of period end		133.8	155.5
Liabilities
Contingent consideration obligations:		0.0	0.0
Total liabilities as of period end		0.0	0.0
Level 2
Cash and cash equivalents
Money market funds	[1]	0.0	0.0
Other current assets
Available-for-sale securities		0.0	0.0
Other non-current assets
Available-for-sale securities		0.0	0.0
Total assets as of period end		0.0	0.0
Liabilities
Contingent consideration obligations:		0.0	0.0
Total liabilities as of period end		0.0	0.0
Level 3
Cash and cash equivalents
Money market funds	[1]	0.0	0.0
Other current assets
Available-for-sale securities		0.0	0.0
Other non-current assets
Available-for-sale securities		1.1	1.1
Total assets as of period end		1.1	1.1
Liabilities
Contingent consideration obligations:		5.9	5.5
Total liabilities as of period end		$ 5.9	$ 5.5

[1] Money market funds include money market deposit account balances of $41.4 million and $91.0 million as of December 31, 2016 and June 30, 2016, respectively.