Business Segments - Earned Premiums by Product Line (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
Entity-Wide Information, Revenue from External Customer [Line Items]
Earned Premiums, Life	$ 96.8	$ 98.4	$ 291.6	$ 294.9
Earned Premiums, Accident and Health	37.1	40.7	112.1	121.2
Earned Premiums, Total	462.8	507.5	1,410.7	1,530.2
Personal Automobile [Member]
Entity-Wide Information, Revenue from External Customer [Line Items]
Earned Premiums, Property and Casualty	205.1	239.1	633.4	729.4
Homeowners [Member]
Entity-Wide Information, Revenue from External Customer [Line Items]
Earned Premiums, Property and Casualty	77.9	82.3	236.6	244.8
Other Personal Property and Casualty Insurance [Member]
Entity-Wide Information, Revenue from External Customer [Line Items]
Earned Premiums, Property and Casualty	31.8	33.5	96.2	101.2
Commercial Automobile [Member]
Entity-Wide Information, Revenue from External Customer [Line Items]
Earned Premiums, Property and Casualty	$ 14.1	$ 13.5	$ 40.8	$ 38.7