Benefits (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Benefits (Textuals) [Abstract]
Pension and Other Postretirement Benefit Contributions			$ 100.0	$ 0.0
Estimated liability of Postemployment benefits	$ 7.0		7.0		$ 3.3
Pension Plan [Member]
Net Periodic Benefit Cost
Service cost	3.9	$ 2.3	7.8	5.0
Interest cost	15.1	17.0	30.3	34.1
Expected return on plan assets	(25.6)	(24.6)	(51.4)	(49.3)
Amortization of:
Prior service cost (credit)	0.5	0.5	1.0	1.0
Actuarial loss	11.4	9.3	23.0	18.4
Net Periodic Benefit Cost	5.3	4.5	10.7	9.2
Other Postretirement Benefit Plan [Member]
Net Periodic Benefit Cost
Service cost	2.1	2.1	4.7	4.3
Interest cost	3.9	4.4	8.1	8.9
Expected return on plan assets	(5.9)	(6.0)	(11.8)	(11.9)
Amortization of:
Transition obligation	0.0	0.0	0.0	0.0
Prior service cost (credit)	(0.3)	(0.4)	(0.6)	(0.9)
Actuarial loss	0.5	0.4	1.0	0.6
Net Periodic Benefit Cost	$ 0.3	$ 0.5	$ 1.4	$ 1.0