Retirement Benefit Plans (Components of net periodic benefit cost) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Retirement Plans [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	$ 1.4	$ 1.2
Interest cost	4.4	5.3
Expected return on plan assets	(5.7)	(6.2)
Amortization of prior service cost/(credit)	0.0	0.0
Amortization of net actuarial gain/(loss)	0.5	0.6
Net periodic benefit cost	0.6	0.9
Medical Plans [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	0.0	0.0
Interest cost	0.0	0.0
Expected return on plan assets	0.0	(0.1)
Amortization of prior service cost/(credit)	(2.0)	(2.2)
Amortization of net actuarial gain/(loss)	(0.1)	0.0
Net periodic benefit cost	$ (2.1)	$ (2.3)