Condensed Consolidated Statements of Cash Flows - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Cash Flows from Operating Activities:
Net Loss	$ (80.1)	$ (86.3)
Adjustments to Reconcile Net Loss to Net Cash Provided by (Used in) Operating Activities:
Net Realized Investment Gains	(6.4)	(1.5)
Impairment Gains (Losses)	(2.1)	8.9
Depreciation and Amortization of Property, Equipment and Software	11.9	13.4
Amortization of Intangibles Assets Acquired	4.3	6.2
Loss from Early Extinguishment of Debt	0.0	3.7
Income (Loss) from Equity Method Investments, Net of Dividends or Distributions	0.8	(5.8)
(Increase) Decrease in Value of Equity and Convertible Securities	(1.7)	28.2
Receivables from Policyholders	(57.4)	14.2
Reinsurance Recoverables	4.1	(0.3)
Deferred Policy Acquisition Costs	(15.9)	(1.6)
Insurance Reserves	(21.8)	(8.7)
Unearned Premiums	73.6	(8.2)
Income Taxes	106.2	(28.2)
Other Assets and Liabilities	(9.6)	31.1
Net Cash Provided by (Used in) Operating Activities, Total	5.2	(18.2)
Cash Flows from Investing Activities:
Proceeds from Sales, Calls and Maturities of Fixed Maturities	154.0	128.6
Proceeds from the Sales or Paydowns of Investments:
Equity Securities	19.5	249.7
Mortgage Loans	18.6	22.8
Other Investments	2.6	20.5
Payments to Acquire Investments [Abstract]
Payments to Acquire Debt Securities, Available-for-Sale	(293.3)	(527.2)
Payments to Acquire Equity Securities, FV-NI	(13.2)	(21.3)
Payments to Acquire Real Estate Held-for-investment	(0.2)	0.0
Payment to Acquire Life Insurance Policy, Investing Activities	0.0	(100.0)
Payments to Acquire Mortgage Notes Receivable	(13.3)	(21.3)
Payments to Acquire Interest in Subsidiaries and Affiliates	4.7	1.9
Net Sales of Short-term Investments	0.7	40.3
Acquisition of Software and Long-lived Assets	(10.0)	(16.0)
Other	1.1	0.7
Net Cash Provided by (Used in) Investing Activities, Total	(138.2)	(225.1)
Cash Flows from Financing Activities:
Repayment of Long-term Debt	0.0	(280.0)
Proceeds from Issuance of Senior Long-term Debt	0.0	396.3
Proceeds from Issuance of Subordinated Long-term Debt	0.0	145.6
Proceeds from Policyholder Contract Obligations	89.3	208.6
Repayment of Policyholder Contract Obligations	(90.0)	(57.8)
Proceeds from Shares Issued under Employee Stock Purchase Plan	1.0	1.3
Dividends Paid	(19.4)	(19.8)
Other	0.3	0.3
Net Cash Provided by (Used in) Financing Activities, Total	(18.8)	392.4
Net (decrease) increase in cash	(151.8)	149.1
Cash, Beginning of Year	212.4	148.2
Cash, End of Period	60.6	297.3
Senior Notes, 3.800 Percent Due February 23, 2033
Cash Flows from Financing Activities:
Payments of Debt Issuance Costs	0.0	(1.2)
5.875% Fixed-Rate Reset Junior Subordinated Debentures due 2062
Cash Flows from Financing Activities:
Payments of Debt Issuance Costs	0.0	(0.9)
Alternative Energy Partnership Investments
Adjustments to Reconcile Net Loss to Net Cash Provided by (Used in) Operating Activities:
Income (Loss) from Equity Method Investments	$ 0.7	$ (16.7)