Business Segments - Segment Net Income (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Segment Reporting Information [Line Items]
Net Operating Income									$ 97.1	$ 159.2	$ 53.8
Income from Continuing Operations	63.3	4.8	9.3	35.2	54.8	68.6	32.5	58.6	112.6	214.5	91.8
Operating Segments [Member]
Segment Reporting Information [Line Items]
Net Operating Income									116.7	189.9	79.9
Operating Segments [Member] | Property and Casualty Insurance [Member]
Segment Reporting Information [Line Items]
Net Operating Income									24.9	100.6	(10.9)
Operating Segments [Member] | Life and Health Insurance [Member]
Segment Reporting Information [Line Items]
Net Operating Income									91.8	89.3	90.8
Corporate, Non-Segment [Member]
Segment Reporting Information [Line Items]
Net Operating Income									(19.6)	(30.7)	(26.1)
Segment Reconciling Items [Member]
Segment Reporting Information [Line Items]
Net Realized Gains on Sales of Investments									25.4	64.4	42.5
Net Impairment Losses Recognized in Earnings									$ 9.9	$ 9.1	$ 4.5