Condensed Consolidated Statements of Cash Flows - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Cash Flows from Operating Activities:
Net Loss	$ (177.2)	$ (158.5)
Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract]
Net Realized Investment Losses (Gains)	8.0	(12.5)
Impairment Gains (Losses)	(1.2)	13.8
Depreciation and Amortization of Property, Equipment and Software	26.2	26.5
Amortization of Intangibles Assets Acquired	7.9	11.2
Loss from Early Extinguishment of Debt	0.0	3.7
Income (Loss) from Equity Method Investments, Net of Dividends or Distributions	(1.3)	(18.3)
(Increase) Decrease in Value of Equity and Convertible Securities	(4.1)	68.7
Goodwill Impairment	49.6	0.0
Receivables from Policyholders	40.3	43.6
Reinsurance Recoverables	11.6	0.3
Deferred Policy Acquisition Costs	(10.6)	(2.1)
Insurance Reserves	(47.7)	(1.8)
Unearned Premiums	(39.2)	(44.3)
Income Taxes	72.6	(46.2)
Other Assets and Liabilities	0.7	4.3
Net Cash Provided by (Used in) Operating Activities, Total	(65.9)	(90.0)
Cash Flows from Investing Activities:
Proceeds from Sales, Calls and Maturities of Fixed Maturities	353.0	564.9
Proceeds from the Sales or Paydowns of Investments:
Equity Securities	32.5	403.7
Mortgage Loans	42.5	46.6
Other Investments	5.1	36.9
Payments to Acquire Investments [Abstract]
Payments to Acquire Debt Securities, Available-for-Sale	(334.8)	(1,025.9)
Payments to Acquire Equity Securities, FV-NI	(26.2)	(39.1)
Payments to Acquire Real Estate Held-for-investment	(0.3)	(2.9)
Payment to Acquire Life Insurance Policy, Investing Activities	0.0	(100.0)
Payments to Acquire Mortgage Notes Receivable	(44.1)	(45.0)
Payments to Acquire Interest in Subsidiaries and Affiliates	11.6	4.9
Net (Purchases) Sales of Short-term Investments	(126.9)	54.0
Acquisition of Software and Long-lived Assets	(25.4)	(23.7)
Settlement Proceeds from Company-Owned Life Insurance	102.2	0.0
Other	(1.1)	2.9
Net Cash Provided by (Used in) Investing Activities, Total	(35.1)	(132.5)
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	114.5	289.6
Repayment of Policyholder Contract Obligations	(115.8)	(89.3)
Proceeds from Shares Issued under Employee Stock Purchase Plan	2.2	2.5
Dividends Paid	(39.6)	(40.0)
Other	0.9	0.3
Net Cash Provided by (Used in) Financing Activities, Total	(37.8)	422.9
Net (decrease) increase in cash	(138.8)	200.4
Cash, Beginning of Year	212.4	148.2
Cash, End of Period	73.6	348.6
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 Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract]
Income (Loss) from Equity Method Investments	$ 1.5	$ (21.6)