Summary Of Accounting Policies And Accounting Changes (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Accounting Policy Disclosures [Line Items]
Reinsurance Recoverables, Including Reinsurance Premium Paid	$ 106.4				$ 108.3				$ 106.4	$ 108.3
Accrued Investment Income Receivable	70.8				68.5				70.8	68.5
Deferred Policy Acquisition Costs	332.0				316.4				332.0	316.4
Write-off of long-lived asset					0.0	$ 0.0	$ 11.1	$ 0.0	0.0	11.1	$ 54.6
Expected Amortization Expense of Ending Present Value of Future Insurance Profits, Net of Interest Accrued [Abstract]
Policyholders’ Benefits and Incurred Losses and Loss Adjustment Expenses	418.3	$ 490.2	$ 436.1	$ 436.2	416.0	$ 378.8	$ 375.1	$ 297.7	1,780.8	1,467.6	$ 1,261.7
Life Insurance Product Line [Member]
Accounting Policy Disclosures [Line Items]
Present value of the future profits embedded in life insurance in force	28.9				32.5				28.9	32.5
Expected Amortization Expense of Ending Present Value of Future Insurance Profits, Net of Interest Accrued [Abstract]
2017									3.1
2018									2.8
2019									2.4
2020									2.0
2021									1.8
Property and Casualty Insurance [Member]
Accounting Policy Disclosures [Line Items]
Present value of the future profits embedded in life insurance in force	9.0				11.2				9.0	11.2
Broker Relationships [Member]
Accounting Policy Disclosures [Line Items]
Assets acquired	$ 16.8				18.1				$ 16.8	18.1
Useful life of intangibles acquired (in years)									15 years
Minimum [Member]
Accounting Policy Disclosures [Line Items]
Useful life of intangibles acquired (in years)									2 years
Minimum [Member] | Traditional Life [Member]
Accounting Policy Disclosures [Line Items]
Liability for Future Policy Benefits, Interest Rate	3.00%								3.00%
Maximum [Member]
Accounting Policy Disclosures [Line Items]
Useful life of intangibles acquired (in years)									5 years
Maximum [Member] | Traditional Life [Member]
Accounting Policy Disclosures [Line Items]
Liability for Future Policy Benefits, Interest Rate	7.00%								7.00%
Change in Accounting Method Accounted for as Change in Estimate [Member]
Accounting Policy Disclosures [Line Items]
Pension Expense									$ (2.7)
Change in Accounting Estimate, Use of Death Master File in Reserving Process [Member]
Expected Amortization Expense of Ending Present Value of Future Insurance Profits, Net of Interest Accrued [Abstract]
Policyholders’ Benefits and Incurred Losses and Loss Adjustment Expenses									77.8
Premium Deficiency [Member]
Accounting Policy Disclosures [Line Items]
Deferred Policy Acquisition Costs	$ (9.7)				$ (9.0)				$ (9.7)	$ (9.0)