Taxes Uncertain Tax Positions (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended	12 Months Ended
	Sep. 30, 2014	Dec. 31, 2013
Uncertain Tax Positions [Line Items]
Amount expected to impact the effective tax rate if recognized	$ 0.4	$ 6.5
Unrecognized Tax Benefits, Period Decrease	7.1
Unrecognized tax benefit decrease related to former GMO non-regulated operations	6.1
Unrecognized Tax Benefits, Income Tax Penalties Accrued		0.6
Unrecognized Tax Benefits, Interest on Income Taxes Accrued		3.2
Interest expense related to unrecognized tax benefits	3.2
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance at beginning of period	9.8	21.4
Reductions for current year tax positions	(0.2)	(0.3)
Reductions for prior year tax positions	(6.9)	(10.5)
Statute expirations	0	(0.3)
Foreign currency translation adjustments	0	(0.5)
Balance at end of period	$ 2.7	$ 9.8