Pension and Other Postretirement Benefits (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2012
Pension Plans
Change in projected benefit obligation:
Projected benefit obligation at beginning of year	$ 1,186.7	$ 1,218.1
Service cost	32.1	32.5	23.0
Interest cost	57.5	53.0	51.3
Benefits paid	(81.0)	(70.6)
Actuarial loss (gain)	53.2	(45.7)
Plan settlements	(0.2)	(0.6)
Plan amendments	(1.3)
Projected benefit obligation at end of year	1,247.0	1,186.7	1,218.1
Change in plan assets:
Fair value of plan assets at beginning of year	930.2	770.9
Actual return	165.7	82.3
Benefits paid	(81.0)	(70.6)
Contributions	9.8	148.2
Plan settlements	(0.3)	(0.6)
Fair value of plan assets at end of year	1,024.4	930.2	770.9
Funded status of the plans
Funded status of the plans	(222.6)	(256.5)
Other Postretirement Plans
Change in projected benefit obligation:
Projected benefit obligation at beginning of year	259.8	282.2
Service cost	4.0	4.4	3.7
Interest cost	12.5	12.2	11.8
Benefits paid	(13.5)	(13.1)
Actuarial loss (gain)	22.4	(25.9)
Projected benefit obligation at end of year	285.2	259.8	282.2
Change in plan assets:
Fair value of plan assets at beginning of year	93.2	85.3
Actual return	13.7	8.2
Benefits paid	(13.5)	(13.1)
Contributions	13.1	12.8
Fair value of plan assets at end of year	106.5	93.2	85.3
Funded status of the plans
Funded status of the plans	$ (178.7)	$ (166.6)