Summary Of Accounting Policies And Accounting Changes (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Jan. 01, 2019	Jan. 01, 2018
Accounting Policy Disclosures [Line Items]
Policyholders’ Benefits and Incurred Losses and Loss Adjustment Expenses	$ 772.8	$ 757.3	$ 499.5	$ 436.9	$ 472.5	$ 440.1	$ 447.4	$ 477.4	$ 2,466.5	$ 1,837.4	$ 1,780.8
Reinsurance Recoverables, Including Reinsurance Premium Paid	158.3				111.6				158.3	111.6
Accrued Investment Income Receivable	77.9				72.8				77.9	72.8
Present Value of Future Insurance Profits, Amortization Expense, Next Five Years [Abstract]
Definite Lived Intangible Assets:	261.0				133.2				261.0	133.2
Deferred Policy Acquisition Costs	470.0				365.3				470.0	365.3
Life Insurance Product Line [Member]
Present Value of Future Insurance Profits, Amortization Expense, Next Five Years [Abstract]
2018	6.3								6.3
2019	4.0								4.0
2020	2.8								2.8
2021	2.2								2.2
2022	1.8								1.8
Value of Business Acquired
Accounting Policy Disclosures [Line Items]
Present value of the future profits embedded in life insurance in force	$ 30.2				$ 26.0				$ 30.2	$ 26.0
Minimum [Member] | Traditional Life [Member]
Accounting Policy Disclosures [Line Items]
Liability for Future Policy Benefits, Interest Rate	3.00%								3.00%
Maximum [Member] | Traditional Life [Member]
Accounting Policy Disclosures [Line Items]
Liability for Future Policy Benefits, Interest Rate	7.00%								7.00%
Change in Accounting Estimate, Use of Death Master File in Reserving Process [Member]
Accounting Policy Disclosures [Line Items]
Policyholders’ Benefits and Incurred Losses and Loss Adjustment Expenses											$ 77.8
AOCI Including Portion Attributable to Noncontrolling Interest [Member] | Accounting Standards Update 2016-01 [Member]
Accounting Policy Disclosures [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets													$ (17.7)
Retained Earnings [Member] | Accounting Standards Update 2016-01 [Member]
Accounting Policy Disclosures [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets													$ 17.7
Scenario, Forecast [Member] | Accounting Standards Update 2016-02 [Member]
Present Value of Future Insurance Profits, Amortization Expense, Next Five Years [Abstract]
Operating Lease, Right-of-Use Asset												$ 85.0