Income Taxes - Effective Income Tax Rate Reconciliation (Detail) - USD ($) $ in Millions	12 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2014
Income tax reconciliation
Provision for income taxes at U.S. statutory rate	$ 164.1	$ 153.6	$ 138.4
Increase (decrease) in Provision for income taxes from:
State taxes, net of federal tax	7.0	5.8	4.0
Foreign taxes	(5.6)	(5.1)	(7.5)
Valuation allowances	(0.3)	(0.9)	(0.7)
Other	(3.8)	(1.6)	(1.7)
Total Provision for income taxes	$ 161.4	$ 151.8	$ 132.5
Tax rate reconciliation (percent)
Provision for income taxes at U.S. statutory rate	35.00%	35.00%	35.00%
Increase (decrease) in Provision for income taxes from:
State taxes, net of federal tax	1.50%	1.30%	1.00%
Foreign taxes	(1.20%)	(1.20%)	(1.90%)
Valuation allowances	(0.10%)	(0.20%)	(0.20%)
Other	(0.70%)	(0.30%)	(0.40%)
Total Provision for income taxes	34.40%	34.60%	33.50%