Employee Benefit Plans (Schedule of Underfunded Plan Assets) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Pension Plan [Member]
Change in benefit obligation:
Benefit obligation, beginning balance	$ 43.4	$ 42.2
Service cost	1.2	1.7	1.4
Interest cost	1.6	1.8	1.9
Change in plan provisions	0	0
Benefits paid	(1.2)	(1.2)
Actuarial (gain) loss	(4.6)	(1.1)
Benefit obligation, ending balance	40.4	43.4	42.2
Change in fair value of plan assets:
Plan assets, beginning balance	0	0
Employer contribution	1.2	1.2
Benefits paid	(1.2)	(1.2)
Plan assets, ending balance	0	0	0
Underfunded status, end of year	(40.4)	(43.4)
Other Benefits [Member]
Change in benefit obligation:
Benefit obligation, beginning balance	26.9	24.6
Service cost	0.4	0.4	0.2
Interest cost	1.0	1.1	0.8
Change in plan provisions	(0.6)	0
Benefits paid	(0.9)	(0.9)
Actuarial (gain) loss	(2.7)	1.7
Benefit obligation, ending balance	24.1	26.9	24.6
Change in fair value of plan assets:
Plan assets, beginning balance	0	0
Employer contribution	0.9	0.9
Benefits paid	(0.9)	(0.9)
Plan assets, ending balance	0	0	0
Underfunded status, end of year	$ (24.1)	$ (26.9)