Pension and Other Postretirement Benefits - Schedule of Amounts Recognized in the Consolidated Balance Sheets (Details) - USD ($) $ in Millions	12 Months Ended
	Jun. 30, 2016	Jun. 30, 2015
Pension Plans
Amounts recognized in accumulated other comprehensive loss:
Net actuarial loss	$ 547.7	$ 422.3
Prior service cost (credit)	2.0	2.4
Total	549.7	424.7
Other changes in plan assets and benefit obligations recognized in other comprehensive loss consist of:
Net actuarial loss	152.8	97.8
Amortization of accumulated net actuarial loss	(27.3)	(16.7)
Prior service cost (credit)	0.0	1.6
Amortization of prior service (cost) benefit	(0.4)	(0.3)
Total, before tax effect	125.1	82.4
Additional information:
Accumulated benefit obligation for all pension plans	1,319.7	1,253.5
Other Postretirement Plans
Amounts recognized in accumulated other comprehensive loss:
Net actuarial loss	61.1	52.3
Prior service cost (credit)	(45.4)	(51.8)
Total	15.7	0.5
Other changes in plan assets and benefit obligations recognized in other comprehensive loss consist of:
Net actuarial loss	11.3	3.6
Amortization of accumulated net actuarial loss	(2.6)	(2.0)
Prior service cost (credit)	0.0	(51.9)
Amortization of prior service (cost) benefit	6.5	0.0
Total, before tax effect	$ 15.2	$ (50.3)