Pension Plans and Other Postretirement Benefits (Components of net periodic benefit) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Pension Benefits [Member]
Components of net periodic benefit cost
Service costs	$ 0.6	$ 0.5	$ 1.2	$ 1.1
Interest costs	0.6	0.6	1.2	1.2
Expected return on plan assets	(2.5)	(2.5)	(5.0)	(5.1)
Recognized net actuarial loss	0.0	0.0	0.0	0.0
Net periodic benefit (gains) costs	(1.3)	(1.4)	(2.6)	(2.8)
Postretirement Benefits [Member]
Components of net periodic benefit cost
Service costs	0.0	0.0	0.0	0.0
Interest costs	0.2	0.1	0.3	0.3
Expected return on plan assets	0.0	0.0	0.0	0.0
Recognized net actuarial loss	0.1	0.3	0.3	0.4
Net periodic benefit (gains) costs	$ 0.3	$ 0.4	$ 0.6	$ 0.7