Pension and Other Postretirement Benefits - Schedule of Reconciliation of Benefit Obligations, Plan Assets and Funded Status of the Plans (Details) - USD ($) $ in Millions	12 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2014
Amounts recognized in the consolidated balance sheets:
Accrued liabilities - current	$ (10.1)	$ (3.3)
Accrued pension liabilities - noncurrent	(509.3)	(334.1)
Accrued postretirement benefits - noncurrent	(116.6)	(111.2)
Pension Plans
Change in projected benefit obligation:
Projected benefit obligation at beginning of year	1,323.1	1,247.0
Service cost	31.2	32.2	$ 32.1
Interest cost	58.0	54.1	57.5
Benefits paid	(126.1)	(81.3)
Actuarial loss	108.8	61.2
Special termination benefits	9.4	8.3
Curtailment gain	0.0	0.0
Plan amendments	0.0	1.6
Projected benefit obligation at end of year	1,404.4	1,323.1	1,247.0
Change in plan assets:
Fair value of plan assets at beginning of year	985.8	1,024.4
Actual return	22.2	32.2
Benefits paid	(126.1)	(81.3)
Contributions	3.2	10.5
Fair value of plan assets at end of year	885.1	985.8	1,024.4
Funded status of the plans	(519.3)	(337.3)
Amounts recognized in the consolidated balance sheets:
Other assets - noncurrent	0.1	0.1
Accrued liabilities - current	(10.1)	(3.3)
Accrued pension liabilities - noncurrent	(509.3)	(334.1)
Accrued postretirement benefits - noncurrent	0.0	0.0
Amounts recognized in the Consolidated Balance Sheets	(519.3)	(337.3)
Other Postretirement Plans
Change in projected benefit obligation:
Projected benefit obligation at beginning of year	236.8	285.2
Service cost	3.3	4.4	4.0
Interest cost	10.4	11.8	12.5
Benefits paid	(13.3)	(13.8)
Actuarial loss	8.8	2.7
Special termination benefits	0.0	0.0
Curtailment gain	0.0	(1.6)
Plan amendments	0.0	(51.9)
Projected benefit obligation at end of year	246.0	236.8	285.2
Change in plan assets:
Fair value of plan assets at beginning of year	111.6	106.5
Actual return	4.3	5.4
Benefits paid	(13.3)	(13.8)
Contributions	13.0	13.5
Fair value of plan assets at end of year	115.6	111.6	$ 106.5
Funded status of the plans	(130.4)	(125.2)
Amounts recognized in the consolidated balance sheets:
Other assets - noncurrent	0.0	0.0
Accrued liabilities - current	(13.8)	(14.0)
Accrued pension liabilities - noncurrent	0.0	0.0
Accrued postretirement benefits - noncurrent	(116.6)	(111.2)
Amounts recognized in the Consolidated Balance Sheets	$ (130.4)	$ (125.2)