Reclassifications Out of Accumulated Other Comprehensive Income (Loss) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Loss	$ (17.1)	$ (22.0)
Other Comprehensive Income Before Reclassifications	4.6
Amounts Reclassified from Accumulated Other Comprehensive Income (Loss)	(0.3)
Net Other Comprehensive Income	4.9	6.9	(5.7)
Reclassifications Out of Accumulated Other Comprehensive Income [Abstract]
AOCI Reclassification, Amortization of Defined Benefit Pension and Other Postretirement Items	(2.7)
AOCI Reclassification, Amortization of Defined Benefit Pension and Other Postretirement items, Prior Service Costs, Before Tax	0.8
AOCI Reclassification, Amortization of Defined Benefit Pension and Other Postretirement Items, Actuarial Gains and Losses, Before Tax	(3.5)
Other Income (Expense) - Other [Member]
Reclassifications Out of Accumulated Other Comprehensive Income [Abstract]
AOCI Reclassification, Unrealized Gains on Available-for-sale Securities, Before Tax	2.2
Income Tax Expense [Member]
Reclassifications Out of Accumulated Other Comprehensive Income [Abstract]
AOCI Reclassification, Unrealized Gains on Available-for-sale Securities, Tax	(0.9)
AOCI Reclassification, Amortization of Defined Benefit Pension and Other Postretirement Items, Tax	1.1
Unrealized Gains and Losses on Available-for-sale Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Loss	(0.1)	(0.1)
Other Comprehensive Income Before Reclassifications	1.3
Amounts Reclassified from Accumulated Other Comprehensive Income (Loss)	1.3
Net Other Comprehensive Income	0
Defined Benefit Pension, Other Postretirement Items [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Loss	(16.7)	(21.5)
Other Comprehensive Income Before Reclassifications	3.2
Amounts Reclassified from Accumulated Other Comprehensive Income (Loss)	(1.6)
Net Other Comprehensive Income	4.8
Gains and Losses on Cash Flow Hedge [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Loss	(0.3)	(0.4)
Other Comprehensive Income Before Reclassifications	0.1
Amounts Reclassified from Accumulated Other Comprehensive Income (Loss)	0
Net Other Comprehensive Income	$ 0.1