Property and Casualty Insurance Reserves (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Beginning Property and Casualty Insurance Reserves: [Abstract]
Property and Casualty Insurance Reserves, Gross of Reinsurance at Beginning of Year	$ 843.5	$ 970.6	$ 1,029.1
Less Reinsurance Recoverables and Indemnification at Beginning of Year	63.4us-gaap_ReinsuranceRecoverables	66.2us-gaap_ReinsuranceRecoverables	74.5us-gaap_ReinsuranceRecoverables
Property and Casualty Insurance Reserves, Net of Reinsurance and Indemnification at Beginning of Year	780.1	904.4	954.6
Incurred Losses and LAE related to:
Prior Years - Incurred Losses and LAE	(57.1)	(64.6)	(31.5)
Total Incurred Losses and LAE	908.3	991.9	1,221.6
Paid Losses and LAE related to:
Prior Years - Paid Losses and LAE	369.6	434.0	470.4
Total Paid Losses and LAE	1,009.4	1,116.2	1,271.8
Property and Casualty Insurance Reserves, Net of Reinsurance and Indemnification at End of Year	679.0	780.1	904.4
Plus Reinsurance and Indemnification Recoverables at End of Year	54.9us-gaap_ReinsuranceRecoverables	63.4us-gaap_ReinsuranceRecoverables	66.2us-gaap_ReinsuranceRecoverables
Property and Casualty Insurance Reserves, Gross of Reinsurance at End of Year	733.9	843.5	970.6
Personal Lines [Member]
Incurred Losses and LAE related to:
Prior Years - Incurred Losses and LAE	(50.9)	56.8	12.6
Commercial Lines [Member]
Incurred Losses and LAE related to:
Prior Years - Incurred Losses and LAE	(6.2)	7.8	18.9
Segment, Continuing Operations [Member]
Incurred Losses and LAE related to:
Current Year - Incurred Losses and LAE	965.4	1,056.5	1,253.1
Prior Years - Incurred Losses and LAE	(53.5)	(59.8)	(25.2)
Paid Losses and LAE related to:
Current Year - Paid Losses and LAE	639.8	682.2	801.4
Prior Years - Paid Losses and LAE	360.4	421.7	451.2
Segment, Continuing Operations [Member] \| Commercial Lines [Member]
Incurred Losses and LAE related to:
Prior Years - Incurred Losses and LAE	(2.6)	3.0	12.6
Segment, Discontinued Operations [Member]
Incurred Losses and LAE related to:
Prior Years - Incurred Losses and LAE	(3.6)	(4.8)	(6.3)
Paid Losses and LAE related to:
Prior Years - Paid Losses and LAE	9.2	12.3	19.2
Segment, Discontinued Operations [Member] \| Commercial Lines [Member]
Incurred Losses and LAE related to:
Prior Years - Incurred Losses and LAE	(3.6)	4.8	6.3
Personal Automobile [Member] \| Personal Lines [Member]
Incurred Losses and LAE related to:
Prior Years - Incurred Losses and LAE	31.6	30.1	(2.2)
Homeowners [Member] \| Personal Lines [Member]
Incurred Losses and LAE related to:
Prior Years - Incurred Losses and LAE	(14.8)	(20.1)	11.7
Other Personal Lines [Member] \| Personal Lines [Member]
Incurred Losses and LAE related to:
Prior Years - Incurred Losses and LAE	$ (4.5)	$ 6.6	$ 3.1

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The amount needed to reflect the estimated ultimate cost of settling claims relating to casualty insurance insured events that have occurred on or before a particular date (ordinarily, the balance sheet date) and the amount needed to provide for the estimated ultimate cost required to investigate and settle claims relating to insured events that have occurred on or before a particular date (ordinarily, the balance sheet date), whether or not reported to the insurer at that date.

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Amount of payments to settle claims incurred in the current period and related claims settlement costs.

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Amount of payments to settle claims incurred in prior periods and related claims settlement costs.

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Amount of expense for claims incurred and costs incurred in the claim settlement process.

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Liability as of the balance sheet date for amounts representing estimated cost of settling unpaid claims under the terms of the underlying insurance policies, less estimated reinsurance recoveries on such claims. This includes an estimate for claims which have been incurred but not reported. Claim adjustment expenses represent the costs estimated to be incurred in the settlement of unpaid claims.

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Amount of payments to settle insured claims and pay costs incurred in the claims settlement process.

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Amount after valuation allowance recoverable including premium paid under reinsurance contracts. Examples include, but are not limited to, settled and unsettled claims, incurred but not reported losses, loss adjustment expense, premium paid, policy benefits and policy reserves.

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Amount of expense for claims incurred in the current reporting period and related claims settlement costs.

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Amount of expense for claims incurred in prior reporting periods and related claims settlement costs.

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