Investments Investments - Net Realized Gains on Sales of Investments (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Fixed Maturities [Member]
Net Investment Income [Line Items]
Gains on Sales	$ 0.2	$ 2.5	$ 5.0	$ 29.6
Equity Securities [Member]
Net Investment Income [Line Items]
Gains on Sales	7.9	0.7	11.7	1.9
Losses on Sales	$ 0	$ (0.2)	$ 0	$ (0.3)