Retirement Plans (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Defined Benefit Pension Plans [Member]
Defined Benefit Plans, Net Periodic Benefit Cost [Abstract]
Service cost	$ 1.8	$ 2.0
Interest cost	2.7	3.3
Expected return on assets	(2.8)	(3.3)
Other	1.1	1.0
Net periodic benefit cost	2.8	3.0
Contributions to pension plans	2.7
Estimated employer contribution to pension plans during current fiscal year	approximately $12.4
Retiree Health Care Plan [Member]
Defined Benefit Plans, Net Periodic Benefit Cost [Abstract]
Service cost	0	0
Interest cost	0.2	0.2
Expected return on assets	0	0
Other	(0.2)	0
Net periodic benefit cost	0	0.2
Contributions to retiree health care plan	$ 0.3