Property and Casualty Insurance Reserves (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward]
Property and Casulty Insurance Reserve - Gross of Reinsurance at Beginning of Year	$ 862.8	$ 733.9
Less Reinsurance Recoverables at Beginning of Year	52.0	54.9
Property and Casualty Insurance Reserves - Net of Reinsurance at Beginning of Year	810.8	679.0
Incurred Losses and LAE Related to Prior Years	2.6	(7.4)
Total Incurred Losses and LAE	344.3	206.8
Paid Losses and LAE Related to Prior Years	183.9	127.8
Total Paid Losses and LAE	304.0	218.9
Property and Casualty Insurance Reserves - Net of Reinsurance at End of Period	851.1	666.9
Plus Reinsurance Recoverables at End of Period	49.3	53.2
Property and Casualty Insurance Reserves - Gross of Reinsurance at End of Period	900.4	720.1
Continuing Operations [Member]
Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward]
Incurred Losses and LAE Related to Current Year	341.7	214.2
Incurred Losses and LAE Related to Prior Years	2.7	(7.4)
Paid Losses and LAE Related to Current Year	120.1	91.1
Paid Losses and LAE Related to Prior Years	180.8	126.0
Discontinued Operations [Member]
Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward]
Incurred Losses and LAE Related to Prior Years	(0.1)	0.0
Paid Losses and LAE Related to Prior Years	3.1	1.8
Property and Casualty, Personal Insurance Product Line [Member]
Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward]
Incurred Losses and LAE Related to Prior Years	5.1	(7.2)
Property and Casualty, Commercial Insurance Product Line [Member]
Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward]
Incurred Losses and LAE Related to Prior Years	(2.5)	(0.2)
Property and Casualty, Commercial Insurance Product Line [Member] | Continuing Operations [Member]
Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward]
Incurred Losses and LAE Related to Prior Years	(2.4)
Property and Casualty, Commercial Insurance Product Line [Member] | Discontinued Operations [Member]
Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward]
Incurred Losses and LAE Related to Prior Years	(0.1)
Personal Automobile [Member] | Property and Casualty, Personal Insurance Product Line [Member]
Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward]
Incurred Losses and LAE Related to Prior Years	9.6	(5.1)
Homeowners [Member] | Property and Casualty, Personal Insurance Product Line [Member]
Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward]
Incurred Losses and LAE Related to Prior Years	(5.1)	(2.6)
Other Personal Lines [Member] | Property and Casualty, Personal Insurance Product Line [Member]
Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward]
Incurred Losses and LAE Related to Prior Years	0.6	$ 0.5
Catastrophe [Member] | Homeowners [Member] | Property and Casualty, Personal Insurance Product Line [Member]
Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward]
Incurred Losses and LAE Related to Prior Years	$ (2.4)