Fair Value of Financial Instruments - Summary of Financial Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Millions		Jun. 30, 2016	Jun. 30, 2015
Cash and cash equivalents:
Money market funds	[1]	$ 121.0	$ 65.5
Other current assets:
Available-for-sale securities		0.1	0.1
Other non-current assets:
Available-for-sale securities		35.5	25.6
Total		156.6	91.2
Liabilities:
Contingent consideration obligations		5.5	15.7
Total		5.5	15.7
Level 1 [Member]
Cash and cash equivalents:
Money market funds	[1]	121.0	65.5
Other current assets:
Available-for-sale securities		0.1	0.1
Other non-current assets:
Available-for-sale securities		34.4	24.5
Total		155.5	90.1
Liabilities:
Contingent consideration obligations		0.0	0.0
Total		0.0	0.0
Level 2 [Member]
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		0.0	0.0
Liabilities:
Contingent consideration obligations		0.0	0.0
Total		0.0	0.0
Level 3 [Member]
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		1.1	1.1
Liabilities:
Contingent consideration obligations		5.5	15.7
Total		$ 5.5	$ 15.7

[1] Money market funds include MMDA account balances of $91.0 million and $34.0 million as of June 30, 2016 and 2015, respectively.