Employee Benefit Plans OPEB Changes in Assets Measured at Fair Value Using Signficant Unobservable Inputs (Details) (Defined Benefit Postretirement Life Insurance [Member], Fair Value, Inputs, Level 3, USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Defined Benefit Postretirement Life Insurance [Member] | Fair Value, Inputs, Level 3
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	$ 11.4	$ 11.5	$ 11.7
Defined Benefit Plan, Actual Return on Plan Assets Still Held	0.2	0.3
Defined Benefit Plan, Contributions by Plan Participants	15.6	16.2
Defined Benefit Plan, Benefits Paid	$ (15.9)	$ (16.7)