Kemper (KMPR) 10-Q 30 Oct 23 2023 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - $ / shares	9 Months Ended
	Sep. 30, 2023	Oct. 26, 2023	Dec. 31, 2022
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2023
Document Transition Report	false
Entity File Number	001-18298
Entity Registrant Name	Kemper Corporation
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	95-4255452
Entity Address, Address Line One	200 E. Randolph Street
Entity Address, Address Line Two	Suite 3300
Entity Address, City or Town	Chicago
Entity Address, State or Province	IL
Entity Address, Postal Zip Code	60601
City Area Code	312
Local Phone Number	661-4600
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding (in shares)		64,087,148
Entity Central Index Key	0000860748
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	Q3
Amendment Flag	false
Common stock, par value (in dollars per share)	$ 0.10		$ 0.10
Common Stock
Cover [Abstract]
Title of 12(b) Security	Common Stock, par value $0.10 per share
Security Exchange Name	NYSE
Entity Listings [Line Items]
Title of 12(b) Security	Common Stock, par value $0.10 per share
Trading Symbol	KMPR
Security Exchange Name	NYSE
5.875% Fixed-Rate Reset Junior Subordinated Debentures due 2062
Cover [Abstract]
Title of 12(b) Security	5.875% Fixed-Rate Reset Junior Subordinated Debentures due 2062
Security Exchange Name	NYSE
Entity Listings [Line Items]
Title of 12(b) Security	5.875% Fixed-Rate Reset Junior Subordinated Debentures due 2062
Trading Symbol	KMPB
Security Exchange Name	NYSE

Condensed Consolidated Statemen

Condensed Consolidated Statements of Income - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Income Statement [Abstract]
Earned Premiums (Changes in Deferred Profit Liability for the Nine and Three Months Ended: 2023 - $51.6 and $15.9; 2022 - $56.8 and $19.1)	$ 1,117.8	$ 1,290.9	$ 3,465.6	$ 3,948.5
Net Investment Income	107	97.8	315.1	316.3
Change in Value of Alternative Energy Partnership Investments	0.8	0.4	2.3	(21.2)
Other Income	2.4	4	5.3	7.3
Income (Loss) from Change in Fair Value of Equity and Convertible Securities	2.8	(11.2)	6.9	(79.9)
Net Realized Investment (Losses) Gains	(30.3)	(12.1)	(38.3)	0.4
Impairment Gains (Losses)	(1.1)	(8.3)	0.1	(22.1)
Total Revenues	1,199.4	1,361.5	3,757	4,149.3
Expenses:
Policyholders’ Benefits and Incurred Losses and Loss Adjustment Expenses (Changes in Liability for Future Policyholder Benefits for the Nine and Three Months Ended: 2023 - $8.6 and $6.1; 2022 - $21.9 and $1.6)	975.2	1,085.3	3,011.9	3,359.6
Insurance Expenses	259	300.5	794.4	913
Loss from Early Extinguishment of Debt	0	0	0	3.7
Interest and Other Expenses	156	63.5	311.7	171.1
Goodwill Impairment	0	0	49.6	0
Total Expenses	1,390.2	1,449.3	4,167.6	4,447.4
Loss before Income Taxes	(190.8)	(87.8)	(410.6)	(298.1)
Income Tax Benefit	44.4	13	87	64.8
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest, Total	(146.4)	(74.8)	(323.6)	(233.3)
Less: Net Loss attributable to Noncontrolling Interest	(0.1)	0	(0.1)	0
Net Loss attributable to Kemper Corporation	$ (146.3)	$ (74.8)	$ (323.5)	$ (233.3)
Earnings Per Share [Abstract]
Basic (in dollars per share)	$ (2.28)	$ (1.17)	$ (5.05)	$ (3.66)
Diluted (in dollars per share)	$ (2.28)	$ (1.17)	$ (5.05)	$ (3.66)

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Net Loss	$ (146.3)	$ (74.8)	$ (323.5)	$ (233.3)
Other Comprehensive Income (Loss) Before Income Taxes
Change in Net Unrecognized Postretirement Benefit Costs	61.4	(0.2)	60.3	(0.3)
(Loss) Gain on Cash Flow Hedges	0	0	(0.1)	5.9
Change in Discount Rate on Future Life Policyholder Benefits	276.8	330.9	217.6	1,420.9
Other Comprehensive Income (Loss) Before Income Taxes	8.8	(81.6)	52.3	(218)
Other Comprehensive Income Tax (Expense) Benefit	(1.4)	17.2	(10.8)	45.8
Other Comprehensive Income (Loss), Net of Taxes	7.4	(64.4)	41.5	(172.2)
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	(139)	(139.2)	(282.1)	(405.5)
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Noncontrolling Interest	0	0	0	0
Net Income (Loss) Attributable to Noncontrolling Interest	(0.1)	0	(0.1)	0
Total Comprehensive Loss	(138.9)	(139.2)	(282)	(405.5)
No Credit Losses Recognized in Condensed Consolidated Statements of Loss
Other Comprehensive Income (Loss) Before Income Taxes
Changes in Net Unrealized Holding Losses on Investment Securities with:	(327.9)	(411.5)	(223.9)	(1,643.2)
Credit Losses Recognized in Condensed Consolidated Statements of Loss
Other Comprehensive Income (Loss) Before Income Taxes
Changes in Net Unrealized Holding Losses on Investment Securities with:	$ (1.5)	$ (0.8)	$ (1.6)	$ (1.3)

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Investments:
Debt Securities, Available-for-Sale	$ 6,474.5	$ 6,894.8
Equity Securities, FV-NI, Current	233.4	243.2
418500000	418.5	278.4
Company-Owned Life Insurance	506.9	586.5
Loans to Policyholders	281.8	283.4
Other Investments	273.1	269.9
Total Investments	8,429.5	8,789.5
Cash	110	212.4
Receivables from Policyholders (Allowance for Credit Losses: 2023 - $13.5; 2022 - $13.1)	1,102.6	1,286.6
Other Receivables	223.4	262.6
Deferred Policy Acquisition Costs	622.2	635.6
Goodwill	1,250.7	1,300.3
Current Income Tax Assets	59.5	167.6
Deferred Income Tax Assets	258.5	129
Other Assets	488.7	530
Total Assets	12,549.3	13,313.6
Insurance Reserves:
Life and Health	3,098.1	3,276.2
Property and Casualty	2,724.5	2,756.9
Total Insurance Reserves	5,822.6	6,033.1
Unearned Premiums	1,485.1	1,704.4
Policyholder Obligations	656.3	701.3
Deferred Income Tax Liabilities	57.8	0
Accrued Expenses and Other Liabilities	777.6	817.3
Long-term Debt, Current and Non-current, at Amortized Cost (Fair Value: 2023 - $1,158.0; 2022 - $1,195.1)	1,388.6	1,386.9
Total Liabilities	10,188.1	10,643
Kemper Corporation Shareholders’ Equity:
Common Stock, $0.10 Par Value, 100,000,000 Shares Authorized; 64,081,099 Shares Issued and Outstanding at September 30, 2023 and 63,912,762 Shares Issued and Outstanding at December 31, 2022	6.4	6.4
Paid-in Capital	1,845.9	1,812.7
Retained Earnings	982.4	1,366.4
Accumulated Other Comprehensive Loss	(473.4)	(514.9)
Total Shareholders’ Equity	2,361.3	2,670.6
Equity, Attributable to Noncontrolling Interest	(0.1)	0
Stockholders' equity	2,361.2	2,670.6
Total Liabilities and Shareholders’ Equity	12,549.3	13,313.6
Variable Interest Entity, Primary Beneficiary
Investments:
Debt Securities, Available-for-Sale	1.6	0
Cash	2.4	0
Receivables from Policyholders (Allowance for Credit Losses: 2023 - $13.5; 2022 - $13.1)	0.1	0
Other Assets	0.1	0
Insurance Reserves:
Property and Casualty	0	0
Unearned Premiums	0.1	0
Accrued Expenses and Other Liabilities	0	0
Equity Method Limited Liability Investments
Investments:
Equity Method Investments	224.1	217
Alternative Energy Partnership Investments
Investments:
Equity Method Investments	$ 17.2	$ 16.3

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Fixed maturities, at amortized cost	$ 7,622.5	$ 7,811.8
Fixed maturities, allowance for credit losses	8.6	9.6
Equity securities, at cost	215.5	247.6
Premium receivables, allowance for credit losses	13.5	13.1
Long-term Debt	$ 1,158	$ 1,195.1
Common stock, par value (in dollars per share)	$ 0.10	$ 0.10
Common stock, shares authorized (in shares)	100,000,000	100,000,000
Common stock, shares issued (in shares)	64,081,099	63,912,762
Common stock, shares outstanding (in shares)	64,081,099	63,912,762
Variable Interest Entity, Primary Beneficiary
Fixed maturities, at amortized cost	$ 1.6	$ 0
Fixed maturities, allowance for credit losses	$ 0	$ 0

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Millions	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Net Loss	$ (146.4)	$ (74.8)	$ (323.6)	$ (233.3)
Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract]
Net Realized Investment Losses (Gains)			38.3	(0.4)
Impairment Gains (Losses)	1.1	8.3	(0.1)	22.1
Depreciation and Amortization of Property, Equipment and Software			39.1	38.9
Amortization of Intangibles Assets Acquired			11	16
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement and Curtailment			70.2	0
Loss from Early Extinguishment of Debt	0	0	0	3.7
Income (Loss) from Equity Method Investments, Net of Dividends or Distributions			(2.9)	(13.7)
(Increase) Decrease in Value of Equity and Convertible Securities	(2.8)	11.2	(6.9)	79.9
Goodwill Impairment			49.6	0
Receivables from Policyholders			184	69.6
Reinsurance Recoverables			11.6	(1.8)
Deferred Policy Acquisition Costs			13.4	4.2
Insurance Reserves			7.9	(25)
Unearned Premiums			(219.3)	(93.4)
Income Taxes			27.5	(62.9)
Other Assets and Liabilities			(2)	4.8
Net Cash Provided by (Used in) Operating Activities, Total			(104.5)	(170.1)
Cash Flows from Investing Activities:
Proceeds from Sales, Calls and Maturities of Fixed Maturities			529.8	1,019.4
Proceeds from the Sales or Paydowns of Investments:
Equity Securities			73.9	458.3
Mortgage Loans			68.9	69.9
Other Investments			11.2	41.9
Payments to Acquire Investments [Abstract]
Payments to Acquire Debt Securities, Available-for-Sale			(362.7)	(1,386.7)
Payments to Acquire Equity Securities, FV-NI			(40.1)	(55.3)
Payments to Acquire Real Estate Held-for-investment			(0.8)	(2.9)
Payment to Acquire Life Insurance Policy, Investing Activities			0	(110)
Payments to Acquire Mortgage Notes Receivable			(76.6)	(67.3)
Payments to Acquire Interest in Subsidiaries and Affiliates			15.9	9.7
Net Purchases of Short-term Investments			(136.5)	(73.6)
Proceeds from Sale of Other Assets, Investing Activities			0	4.9
Acquisition of Software and Long-lived Assets			(39.1)	(27.1)
Settlement Proceeds from Company-Owned Life Insurance			102.2	0
Other			(9.1)	8.6
Net Cash Provided by (Used in) Investing Activities, Total			105.2	(129.6)
Cash Flows from Financing Activities:
Repayment of Long-term Debt			0	(280)
Proceeds from Issuance of Senior Long-term Debt			0	396.3
Proceeds from Issuance of Subordinated Long-term Debt			0	145.6
Proceeds from Policyholder Contract Obligations			123.3	319.9
Repayment of Policyholder Contract Obligations			(168.4)	(120.1)
Proceeds from Shares Issued under Employee Stock Purchase Plan			3.3	3.8
Dividends Paid			(59.8)	(59.9)
Other			0.9	0.3
Net Cash Provided by (Used in) Financing Activities, Total			(100.7)	403.8
Net increase (decrease) in cash, Including Held-for-Sale			(100)	104.1
Cash at end of period, Including Held-for-Sale	112.4	252.3	112.4	252.3	$ 212.4
Net increase (decrease) in cash, Held-for-Sale			0	3.1
Cash at beginning of year, Held-for-Sale			0	0	0
Cash at end of period, Held-for-Sale	0	3.1	0	3.1	0
Net (decrease) increase in cash			(100)		101
Cash, Beginning of Year			212.4	148.2	148.2
Cash, End of Period	$ 112.4	$ 249.2	112.4	249.2	$ 212.4
Senior Notes, 3.800 Percent Due February 23, 2033
Cash Flows from Financing Activities:
Payments of Debt Issuance Costs			0	(1.2)
5.875% Fixed-Rate Reset Junior Subordinated Debentures due 2062
Cash Flows from Financing Activities:
Payments of Debt Issuance Costs			0	(0.9)
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			$ 2.3	$ (21.2)

Consolidated Statements of Shar

Consolidated Statements of Shareholders’ Equity - USD ($) shares in Millions, $ in Millions	Total	Common Stock	Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Loss	Noncontrolling Interest
Beginning balance (in shares) at Dec. 31, 2021		63.7
Beginning balance at Dec. 31, 2021	$ 3,129.7	$ 6.4	$ 1,790.7	$ 1,734.2	$ (401.6)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Loss	(233.3)			(233.3)
Other Comprehensive Income (Loss), Net of Tax	$ (172.2)				(172.2)
Dividends paid to shareholders per share (in dollars per share)	$ 0.93
Cash Dividends and Dividend Equivalents to Shareholders	$ (60.3)			(60.3)
Shares Issued Under Employee Stock Purchase Plan (Note 14)		$ 0.1	3.8
Shares Issued Under Employee Stock Purchase Plan (Note 14)	3.8
Equity-based Compensation Cost	28.5		28.5
Equity-based Awards, Net of Shares Exchanged (in shares)		0.1
Equity-based Awards, Net of Shares Exchanged	(1.7)	$ 0	(0.8)	(0.9)
Ending balance (in shares) at Sep. 30, 2022		63.9
Ending balance at Sep. 30, 2022	2,694.5	$ 6.4	1,822.2	1,439.7	(573.8)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Loss	(233.3)
Beginning balance (in shares) at Jun. 30, 2022		63.8
Beginning balance at Jun. 30, 2022	2,844.1	$ 6.4	1,812.5	1,534.6	(509.4)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Loss	(74.8)			(74.8)
Other Comprehensive Income (Loss), Net of Tax	$ (64.4)				(64.4)
Dividends paid to shareholders per share (in dollars per share)	$ 0.31
Cash Dividends and Dividend Equivalents to Shareholders	$ (20.1)			(20.1)
Shares Issued Under Employee Stock Purchase Plan (Note 14)		$ 0.1	1.3
Shares Issued Under Employee Stock Purchase Plan (Note 14)	1.3
Equity-based Compensation Cost	8.3		8.3
Equity-based Awards, Net of Shares Exchanged (in shares)		0
Equity-based Awards, Net of Shares Exchanged	0.1	$ 0	0.1	0
Ending balance (in shares) at Sep. 30, 2022		63.9
Ending balance at Sep. 30, 2022	2,694.5	$ 6.4	1,822.2	1,439.7	(573.8)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Loss	(74.8)
Beginning balance (in shares) at Dec. 31, 2022		63.9
Beginning balance at Dec. 31, 2022	2,670.6	$ 6.4	1,812.7	1,366.4	(514.9)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Loss	(323.5)			(323.5)		$ (0.1)
Other Comprehensive Income (Loss), Net of Tax	$ 41.5				41.5
Dividends paid to shareholders per share (in dollars per share)	$ 0.93
Cash Dividends and Dividend Equivalents to Shareholders	$ (59.8)			(59.8)
Shares Issued Under Employee Stock Purchase Plan (Note 14)		$ 0.1	3.2
Shares Issued Under Employee Stock Purchase Plan (Note 14)	3.2
Equity-based Compensation Cost	30		30
Equity-based Awards, Net of Shares Exchanged (in shares)		0.1
Equity-based Awards, Net of Shares Exchanged	(0.7)	$ 0	0	(0.7)
Ending balance (in shares) at Sep. 30, 2023		64.1
Ending balance at Sep. 30, 2023	2,361.2	$ 6.4	1,845.9	982.4	(473.4)	(0.1)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Loss	(323.6)
Beginning balance (in shares) at Jun. 30, 2023		64
Beginning balance at Jun. 30, 2023	2,512.2	$ 6.4	1,837.6	1,149	(480.8)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Loss	(146.3)			(146.3)		(0.1)
Other Comprehensive Income (Loss), Net of Tax	$ 7.4				7.4
Dividends paid to shareholders per share (in dollars per share)	$ 0.31
Cash Dividends and Dividend Equivalents to Shareholders	$ (20.2)			(20.2)
Shares Issued Under Employee Stock Purchase Plan (Note 14)		$ 0.1	1
Shares Issued Under Employee Stock Purchase Plan (Note 14)	1
Equity-based Compensation Cost	7.3		7.3
Equity-based Awards, Net of Shares Exchanged (in shares)		0
Equity-based Awards, Net of Shares Exchanged	(0.1)	$ 0	0	(0.1)
Ending balance (in shares) at Sep. 30, 2023		64.1
Ending balance at Sep. 30, 2023	2,361.2	$ 6.4	$ 1,845.9	$ 982.4	$ (473.4)	$ (0.1)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Loss	$ (146.4)

Interim Condensed Consolidated

Interim Condensed Consolidated Statements of Income (Parenthetical) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Income Statement [Abstract]
Changes in liability for future policyholder benefits	$ 6.1	$ 1.6	$ 8.6	$ 21.9
Changes in deferred profit liability	15.9	19.1	51.6	56.8
Less: Net Loss attributable to Noncontrolling Interest	(0.1)	0	(0.1)	0
Net Loss	(146.3)	(74.8)	(323.5)	(233.3)
Net Loss	(146.4)	(74.8)	(323.6)	(233.3)
Loss before Income Taxes	$ (190.8)	$ (87.8)	$ (410.6)	$ (298.1)

Basis of Presentation and Accou

Basis of Presentation and Accounting Policies	9 Months Ended
	Sep. 30, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation and Accounting Policies	Basis of Presentation and Accounting Policies The unaudited Condensed Consolidated Financial Statements include the accounts of Kemper Corporation (“Kemper”) and its subsidiaries which include property and casualty subsidiaries, life subsidiaries, a health subsidiary through the date of its sale of December 1, 2022 (collectively referred to herein as the “Company”), and a variable interest entity (“VIE”) in which the Company is considered the primary beneficiary. The unaudited Condensed Consolidated Financial Statements included herein have been prepared in accordance with generally accepted accounting principles in the United States of America (“GAAP”) on a basis consistent with reporting interim financial information pursuant to the rules and regulations for Form 10-Q and Article 10 of Regulation S-X of the SEC and include the accounts of Kemper Corporation and its subsidiaries. All intercompany accounts and transactions have been eliminated. Certain financial information that is included in the annual financial statements, including certain financial statement footnote disclosures, prepared in accordance with GAAP is not required by the rules and regulations of the SEC for interim financial reporting and has been condensed or omitted. In the opinion of the Company’s management, the Condensed Consolidated Financial Statements include all adjustments necessary to fairly present the financial position, results of operations and cash flows for the periods presented. The preparation of financial statements requires significant management estimates. Due to this factor and other factors, such as the seasonal nature of some portions of the insurance business, annualizing the results of operations for the nine months ended September 30, 2023 would not necessarily be indicative of the results expected for the full fiscal year. The accompanying Condensed Consolidated Financial Statements should be read in conjunction with the Company’s Consolidated Financial Statements and related notes included in Kemper’s Annual Report for the year ended December 31, 2022, except for Note 7 “Liability for Future Policyholder Benefits”, Note 8 “Deferred Policy Acquisition Costs”, Note 13 “Other Comprehensive Income (Loss) and Accumulated Other Comprehensive Loss” and Note 16 “Policyholder Obligations”, which were impacted due to the implementation of Financial Accounting Standards Board (FASB) Accounting Standards Update (ASU) 2018-12 Financial Services-Insurance (Topic 944): Targeted Improvements to Accounting for Long-Duration Contracts. Adoption of New Accounting Guidance The Company has adopted all recently issued accounting pronouncements with effective dates prior to September 30, 2023. Other than discussed below, there were no adoptions of accounting pronouncements during the nine months ended September 30, 2023 that had a material impact on the Company’s Condensed Consolidated Financial Statements. Guidance Adopted in 2023 The Company adopted ASU 2018-12 for the liability for future policyholder benefits and deferred acquisition costs on a modified retrospective basis as of January 1, 2023, such that those balances were adjusted to conform to ASU 2018-12 on January 1, 2021. The new standard requires cash flow assumptions used to measure the liability for future policyholder benefits for nonparticipating traditional and limited pay long-duration contracts be reviewed at least annually, and if there is a change, updated with the recognition and remeasurement recorded in net income. It also requires the discount rate used in measuring the liability to be an upper-medium grade fixed-income instrument yield, which is to be updated at each reporting period, and recognized in other comprehensive income. ASU 2018-12 simplifies the amortization of deferred acquisition costs to a constant level basis over the expected term of the contract, requires all market risk benefits to be measured at fair value, and enhances certain presentation and disclosure requirements, as discussed in Note 7 and Note 8. As a result of the adoption of ASU 2018-12, beginning retained earnings was reduced by $25.1 million and Accumulated Other Comprehensive Income (“AOCI”) reduced by $1,030.3 million as of January 1, 2021. The table below presents the transition adjustment for the adoption of ASU 2018-12: Pre-Adoption Balance 12/31/2020 Adjustments to AOCI Adjustments to Retained Earnings Post- Adoption Balance 1/1/2021 Retained Earnings $ 2,071.2 — (25.1) $ 2,046.1 AOCI $ 680.5 (1,030.3) — $ (349.8) Note 1 - Basis of Presentation and Accounting Policies (Continued) For the liability for future policyholder benefits, the net transition adjustment is related to the difference in the historical discount rates used pre-transition and the discount rate at December 31, 2020. At transition, there were no adjustments related to premium deficiencies, as the balance is only applicable to Kemper’s universal life contracts which are stated at account value. The effects of adoption of ASU 2018-12 on the Condensed Consolidated Statement of Loss for the nine months ended September 30, 2022 were as follows: Prior to Adoption Effect of Adoption Post- Adoption Balance Earned Premiums $ 3,999.3 (50.8) $ 3,948.5 Policyholders’ Benefits and Incurred Losses and Loss Adjustment Expenses $ 3,426.1 (66.5) $ 3,359.6 Insurance Expenses $ 913.0 — $ 913.0 Income Tax Benefit $ 68.1 (3.3) $ 64.8 Net Loss attributable to Kemper Corporation $ (245.7) 12.4 $ (233.3) Net Loss Per Unrestricted Share attributable to Kemper Corporation: Basic $ (3.85) $ 0.19 $ (3.66) Diluted $ (3.85) $ 0.19 $ (3.66) The effects of adoption of ASU 2018-12 on the Condensed Consolidated Statement of Loss for the three months ended September 30, 2022 were as follows: Prior to Adoption Effect of Adoption Post- Adoption Balance Earned Premiums $ 1,307.0 (16.1) $ 1,290.9 Policyholders’ Benefits and Incurred Losses and Loss Adjustment Expenses $ 1,102.4 (17.1) $ 1,085.3 Insurance Expenses $ 301.3 (0.8) $ 300.5 Income Tax Benefit $ 13.4 (0.4) $ 13.0 Net Loss attributable to Kemper Corporation $ (76.2) 1.4 $ (74.8) Net Loss Per Unrestricted Share attributable to Kemper Corporation: Basic $ (1.19) $ 0.02 $ (1.17) Diluted $ (1.19) $ 0.02 $ (1.17) The effects of adoption of ASU 2018-12 on the Condensed Consolidated Balance Sheet as of December 31, 2022 were as follows: Prior to Adoption Effect of Adoption Post- Adoption Balance Deferred Policy Acquisition Costs $ 625.6 10.0 $ 635.6 Deferred Income Tax Assets $ 189.4 (60.4) $ 129.0 Total Assets $ 13,364.0 (50.4) $ 13,313.6 Life and Health Insurance Reserves $ 3,554.0 (277.8) $ 3,276.2 Total Liabilities $ 10,920.8 (277.8) $ 10,643.0 Retained Earnings $ 1,380.1 (13.7) $ 1,366.4 Accumulated Other Comprehensive Loss $ (756.0) 241.1 $ (514.9) Total Shareholders’ Equity attributable to Kemper Corporation $ 2,443.2 227.4 $ 2,670.6 Note 1 - Basis of Presentation and Accounting Policies (Continued) The effects of adoption of ASU 2018-12 on the Condensed Consolidated Statement of Comprehensive Loss for the nine months ended September 30, 2022 were as follows: Prior to Adoption Effect of Adoption Post- Adoption Balance Change in Discount Rate on Future Life Policyholder Benefits $ — 1,420.9 $ 1,420.9 Other Comprehensive Loss Before Income Taxes $ (1,638.9) 1,420.9 $ (218.0) Other Comprehensive Income Tax Benefit $ 344.2 (298.4) $ 45.8 Other Comprehensive Loss, Net of Taxes $ (1,294.7) 1,122.5 $ (172.2) Total Comprehensive Loss $ (1,540.4) 1,134.9 $ (405.5) The effects of adoption of ASU 2018-12 on the Condensed Consolidated Statement of Comprehensive Loss for the three months ended September 30, 2022 were as follows: Prior to Adoption Effect of Adoption Post- Adoption Balance Change in Discount Rate on Future Life Policyholder Benefits $ — 330.9 $ 330.9 Other Comprehensive Loss Before Income Taxes $ (412.5) 330.9 $ (81.6) Other Comprehensive Income Tax Benefit $ 86.7 (69.5) $ 17.2 Other Comprehensive Loss, Net of Taxes $ (325.8) 261.4 $ (64.4) Total Comprehensive Loss $ (402.0) 262.8 $ (139.2) The effects of adoption of ASU 2018-12 on the Condensed Consolidated Statement of Cash Flows for the nine months ended September 30, 2022 were as follows: Prior to Adoption Effect of Adoption Post- Adoption Balance Cash Flows from Operating Activities: Net Loss $ (245.7) 12.4 $ (233.3) Change in Deferred Policy Acquisition Costs $ 4.2 — $ 4.2 Change in Insurance Reserves $ (9.3) (15.7) $ (25.0) Change in Income Taxes $ (66.2) 3.3 $ (62.9) Net Cash Used in Operating Activities $ (170.1) — $ (170.1) Guidance Not Yet Adopted In March 2023, the FASB issued ASU 2023-02 Accounting for Investments in Tax Credit Structures Using the Proportional Amortization Method , which expands the use of the proportional amortization method of accounting to equity investments in other tax credit structures that meet certain criteria. The proportional amortization method results in the tax credit investment being amortized in proportion to the allocation of tax credits and other tax benefits in each period, and a net presentation within the income tax line item. ASU 2023-02 is effective for annual periods beginning after December 15, 2023 and interim periods within those annual periods. The Company is currently evaluating the impact of this guidance on its financial statements. Significant Accounting Policies Related to ASU 2018-12 The below outlines those significant accounting policies related to ASU 2018-12 that were effective January 1, 2023. Liability for Future Policyholder Benefits A liability for future policyholder benefits, which is the present value of estimated future policyholder benefits to be paid to or on behalf of policyholders and certain related expenses, less the present value of estimated future net premiums to be collected from policyholders, is accrued as premium revenue is recognized. The liability is estimated using current assumptions that Note 1 - Basis of Presentation and Accounting Policies (Continued) include discount rate, mortality, lapses and expenses. These current assumptions are based on judgments that consider the Company’s historical experience, industry data, and other factors. The liability is adjusted for differences between actual and expected experience. The Company reviews and updates its estimate of cash flows expected over the lifetime of a group of contracts using actual historical experience quarterly and current future cash flow assumptions at least annually to calculate its revised net premium ratio. The revised net premium ratios are then used to calculate an updated liability for future policyholder benefits for the current reporting period, discounted at the original contract issuance discount rate. The Company has elected to use expense assumptions that are locked in at contract inception and are not subsequently reviewed or updated. Resulting changes in the liability due to differences in actual versus expected experience, changes in current cash flow assumptions, and prefunding and payout of benefits compared to the carrying amount of the liability as of that same date are recorded as a separate component of benefit expense in the Condensed Consolidated Statements of Loss. The current discount rate assumption is an equivalent spot rate curve of annually compounded rates at monthly increments that is derived based on A-credit rated fixed-income instruments reflecting the duration characteristics of the liability. The Company utilizes published corporate yield curves from Bloomberg’s BVAL Investment Grade Corporate Sector curve. The current discount rate assumption is updated quarterly and used to remeasure the liability at the reporting date, with the resulting change reflected in Other Comprehensive Income (Loss). For liability cash flows that are projected beyond the maximum observable point on the yield curve, the yield grades to an ultimate forward rate. Deferred Profit Liability For limited-payment products, gross premiums received in excess of net premiums are deferred at initial recognition as a deferred profit liability (“DPL”). Gross premiums are measured using assumptions consistent with those used in the measurement of the liability for future policyholder benefits, including discount rate, mortality, lapses, and expenses. The DPL is amortized and recognized as premium revenue in proportion to insurance in force for nonparticipating limited-payment contracts. Interest is accreted on the balance of the DPL using the discount rate determined at contract issuance. The Company reviews and updates its estimates of cash flows for the DPL at the same time as the estimates of cash flows for the liability for future policyholder benefits. When cash flows are updated, the updated estimates are used to recalculate the DPL at contract issuance. The recalculated DPL as of the beginning of the current reporting period is compared to the carrying amount of the DPL as of the beginning of the current reporting period, and any difference is recognized as either an increase or decrease to Earned Premiums. Deferred Policy Acquisition Costs Deferred costs are grouped by contract type and issue year into cohorts consistent with the grouping used in estimating the associated liability. These deferred costs are amortized on a constant level basis for grouped contracts over the expected term of the related contracts to approximate straight-line amortization. The expected term of the contract used for amortization is determined using mortality and termination assumptions that are based on the Company’s experience, industry data, and other factors and are consistent with those used for the liability for future policyholder benefits. If those projected assumptions change in future periods, they will be reflected in the straight-line amortization horizon at that time. Unexpected terminations, due to higher mortality and termination experience than expected, are recognized in the current period as a reduction of the capitalized balances. Amortization of deferred policy acquisition costs is included in Insurance Expenses in the Condensed Consolidated Statements of Loss.

Net Income Per Unrestricted Sha

Net Income Per Unrestricted Share	9 Months Ended
	Sep. 30, 2023
Earnings Per Share [Abstract]
Net Income Per Unrestricted Share	Per Unrestricted ShareThe Company’s awards of deferred stock units granted to Kemper’s non-employee directors prior to 2019 contain rights to receive non-forfeitable dividend equivalents and participate in the undistributed earnings with common shareholders. Accordingly, the Company is required to apply the two-class method of computing basic and diluted earnings per share. Note 2 - Net Loss Per Unrestricted Share (Continued) A reconciliation of the numerator and denominator used in the calculation of Basic Net Loss Per Unrestricted Share and Diluted Net Loss Per Unrestricted Share for the nine and three months ended September 30, 2023 and 2022 is presented below. Nine Months Ended Three Months Ended (Dollars in Millions, except per share amounts) Sep 30, Sep 30, Sep 30, Sep 30, Net Loss attributable to Kemper Corporation $ (323.5) $ (233.3) $ (146.3) $ (74.8) Less: Net Loss Attributed to Participating Awards — — — — Net Loss Attributed to Unrestricted Shares (323.5) (233.3) (146.3) (74.8) Dilutive Effect on Income of Equity-based Compensation Equivalent Shares — — — — Diluted Net Loss Attributed to Unrestricted Shares $ (323.5) $ (233.3) $ (146.3) $ (74.8) (Number of Shares in Thousands) Weighted-average Unrestricted Shares Outstanding 64,004.4 63,804.4 64,056.9 63,852.8 Equity-based Compensation Equivalent Shares — — — — Weighted-average Unrestricted Shares and Equivalent Shares Outstanding Assuming Dilution 64,004.4 63,804.4 64,056.9 63,852.8 Net Loss attributable to Kemper Corporation per Unrestricted Share: (Per Unrestricted Share in Whole Dollars) Basic Net Loss Per Unrestricted Share $ (5.05) $ (3.66) $ (2.28) $ (1.17) Diluted Net Loss Per Unrestricted Share $ (5.05) $ (3.66) $ (2.28) $ (1.17)

Dispositions

Dispositions	9 Months Ended
	Sep. 30, 2023
Discontinued Operations and Disposal Groups [Abstract]
Dispositions	Dispositions Disposition of Reserve National Insurance Company In July 2022, the Company entered into a definitive agreement to sell Reserve National Insurance Company and its wholly-owned subsidiaries (collectively, “Reserve National”) to Medical Mutual of Ohio, for approximately $90.0 million in total consideration. The sale closed on December 1, 2022 and a loss of $1.6 million, net of income tax, was recorded for the year ended December 31, 2022. Subsequent adjustments to this purchase price could occur pursuant to the definitive agreement but are not expected to be material. The Company reported Reserve National’s results of operations in the Life Insurance segment through December 1, 2022.

Intangible Assets, Goodwill and

Intangible Assets, Goodwill and Other	9 Months Ended
	Sep. 30, 2023
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill Disclosure	GoodwillDuring the second quarter of 2023, the Company identified impairment indicators impacting the fair value of the Preferred Property & Casualty Insurance business in connection with ongoing evaluation of strategic alternatives for the Preferred Insurance business. As a result, the business’s fair value was determined using a combination of available market information, market comparisons and a discounted cash flow valuation method based on the present value of future earnings. The fair value calculated in the second quarter of 2023 was lower than the carrying value of the business, resulting in a pre-tax impairment charge of $49.6 million and an after-tax impairment charge of $45.5 million. A substantial portion of the goodwill that was impaired was not tax deductible. The goodwill impairment charge is reported separately in the Condensed Consolidated Statements of Loss for the nine months ended September 30, 2023, with a corresponding reduction to goodwill in the Condensed Consolidated Balance Sheet as of September 30, 2023.

Business Segments

Business Segments	9 Months Ended
	Sep. 30, 2023
Segment Reporting [Abstract]
Business Segments	Business SegmentsIn the third quarter of 2023, the Company announced that it will exit the Preferred Property and Casualty Insurance business and will actively reduce the business beginning in third quarter 2023, with all policies being non-renewed or canceled in accordance with applicable state regulations. In connection with the exit, the Company changed its segment measure of performance to exclude the results of the Preferred Property and Casualty Insurance business from Segment Adjusted Net Operating Loss effective July 1, 2023, since the results are irrelevant to ongoing operations of the Company and do not qualify for Discontinued Operations under U.S. GAAP. The results of this business, previously reported as a reportable segment, are Note 5 - Business Segments (Continued) now reflected as Non-Core Operations and presented as a reconciling item between Segment Adjusted Operating Net Loss and Net Loss. Prior period amounts have been recast to reflect the change in reportable segments and the segment measure of performance. As of September 30, 2023, the Company principally conducts its operations through two segments: Specialty Property & Casualty Insurance and Life Insurance. The Specialty Property & Casualty Insurance segment’s principal products are specialty and commercial automobile insurance. These products are distributed primarily through independent agents and brokers. The Life Insurance segment’s principal products are individual life, accident, supplemental health and property insurance. Career agents employed by the Company distribute these products. This segment has historically been referred to as “Life & Health Insurance.” The results of the segment are unchanged. Corporate and Other operations include interest expense, board of director fees, and general corporate expenses incurred by the Company which are not allocated to other businesses. Segment Adjusted Operating (Loss) Income The Company analyzes the operating performance of each segment using segment adjusted operating (loss) income. Segment adjusted operating (loss) income does not equate to “loss before income taxes” or “net loss” as determined in accordance with U.S. GAAP but is the measure of segment profit or loss used by the Company’s Chief Operating Decision Maker (“CODM”) to evaluate segment performance and allocate resources, and consistent with authoritative guidance, is the measure of segment performance presented below. Segment adjusted operating (loss) income is calculated by adjusting each segment’s loss before income taxes for the following items: (i) Income (Loss) from Change in Fair Value of Equity and Convertible Securities ; (ii) Net Realized Investment (Losses) Gains ; (iii) Impairment Gains (Losses) ; (iv) Acquisition and Disposition Related Transaction, Integration, Restructuring and Other Costs; (v) Debt Extinguishment, Pension Settlement and Other Charges; (vi) Goodwill Impairment Charge; (vii) Non-Core Operations; and (viii) Significant non-recurring or infrequent items that may not be indicative of ongoing operations These items are important to an understanding of overall results of operations. Segment adjusted operating (loss) income is not a substitute for income determined in accordance w ith U.S. GAAP, and the Company’s definition of segment adjusted operating (loss) income may differ from that used by other companies. The Company, however, believes that the presentation of segment adjusted consolidated operating (loss) income as measured for management purposes enhances the understanding of results of operations by highlighting the results from ongoing operations and the underlying profitability factors of its businesses. Note 5 - Business Segments (Continued) Earned Premiums by product line, including a reconciliation to Total Earned Premiums, for the nine and three months ended September 30, 2023 and 2022 were: Nine Months Ended Three Months Ended (Dollars in Millions) Sep 30, Sep 30, Sep 30, Sep 30, Specialty Property & Casualty Insurance: Personal Automobile $ 2,278.5 $ 2,666.3 $ 724.0 $ 858.8 Commercial Automobile 488.4 398.5 166.4 140.7 Life Insurance: Life 251.9 253.8 84.9 84.3 Accident and Health 17.5 136.8 5.8 45.9 Property 34.2 38.3 11.4 11.9 Total Segment Earned Premiums $ 3,070.5 $ 3,493.7 $ 992.5 $ 1,141.6 Non-Core Operations 395.1 454.8 125.3 149.3 Total Earned Premiums $ 3,465.6 $ 3,948.5 $ 1,117.8 $ 1,290.9 Segment Revenues, including a reconciliation to Total Revenues, for the nine and three months ended September 30, 2023 and 2022 were: Nine Months Ended Three Months Ended (Dollars in Millions) Sep 30, Sep 30, Sep 30, Sep 30, Segment Revenues: Specialty Property & Casualty Insurance: Earned Premiums $ 2,766.9 $ 3,064.8 $ 890.4 $ 999.5 Net Investment Income 125.7 102.8 42.7 33.9 Change in Value of Alternative Energy Partnership Investments 1.3 (10.6) 0.5 0.3 Other Income 3.2 5.0 1.6 2.3 Total Specialty Property & Casualty Insurance 2,897.1 3,162.0 935.2 1,036.0 Life Insurance: Earned Premiums 303.6 428.9 102.1 142.1 Net Investment Income 146.3 163.9 49.4 52.6 Change in Value of Alternative Energy Partnership Investments 0.6 (5.6) 0.2 0.1 Other (Loss) Income (0.4) (0.8) (0.1) — Total Life Insurance 450.1 586.4 151.6 194.8 Total Segment Revenues 3,347.2 3,748.4 1,086.8 1,230.8 Income (Loss) from Change in Fair Value of Equity and Convertible Securities 6.9 (79.9) 2.8 (11.2) Net Realized Investment (Losses) Gains (38.3) 0.4 (30.3) (12.1) Net Impairment Gains (Losses) Recognized in Earnings 0.1 (22.1) (1.1) (8.3) Non-Core Operations 431.7 486.0 138.0 161.1 Other 9.4 16.5 3.2 1.2 Total Revenues $ 3,757.0 $ 4,149.3 $ 1,199.4 $ 1,361.5 Note 5 - Business Segments (Continued) Adjusted Consolidated Operating (Loss) Income, including a reconciliation to Loss before Income Taxes, for the nine and three months ended September 30, 2023 and 2022 was: Nine Months Ended Three Months Ended (Dollars in Millions) Sep 30, Sep 30, Sep 30, Sep 30, Segment Adjusted Operating (Loss) Income: Specialty Property & Casualty Insurance $ (132.9) $ (150.4) $ (43.2) $ (39.2) Life Insurance 42.4 51.5 17.5 15.6 Total Segment Adjusted Operating Loss (90.5) (98.9) (25.7) (23.6) Corporate and Other Adjusted Operating Loss From: Other (41.5) (32.2) (13.3) (16.6) Corporate and Other Adjusted Operating Loss (41.5) (32.2) (13.3) (16.6) Adjusted Consolidated Operating Loss (132.0) (131.1) (39.0) (40.2) Income (Loss) from Change in Fair Value of Equity and Convertible Securities 6.9 (79.9) 2.8 (11.2) Net Realized Investment (Losses) Gains (38.3) 0.4 (30.3) (12.1) Impairment Gains (Losses) 0.1 (22.1) (1.1) (8.3) Acquisition and Disposition Related Transaction, Integration, Restructuring and Other Costs (101.9) (27.3) (43.3) (12.7) Debt Extinguishment, Pension Settlement and Other Charges (70.2) (3.7) (70.2) — Goodwill Impairment Charge (49.6) — — — Non-Core Operations (25.5) (34.4) (9.6) (3.3) Loss before Income Taxes attributable to Kemper Corporation $ (410.5) $ (298.1) $ (190.7) $ (87.8) Loss before Income Taxes Noncontrolling Interest (0.1) — (0.1) — Loss before Income Taxes $ (410.6) $ (298.1) $ (190.8) $ (87.8) Note 5 - Business Segments (Continued) Adjusted Consolidated Net Operating Loss, including a reconciliation to Net Loss, for the nine and three months ended September 30, 2023 and 2022 was: Nine Months Ended Three Months Ended (Dollars in Millions and Net of Income Taxes) Sep 30, Sep 30, Sep 30, Sep 30, Segment Adjusted Net Operating (Loss) Income: Specialty Property & Casualty Insurance $ (102.4) $ (112.3) $ (33.2) $ (28.7) Life Insurance 36.8 45.8 14.7 14.0 Total Segment Adjusted Net Operating Loss (65.6) (66.5) (18.5) (14.7) Corporate and Other Adjusted Net Operating Loss From: Other (32.2) (26.4) (9.4) (12.3) Total Corporate and Other Adjusted Net Operating Loss (32.2) (26.4) (9.4) (12.3) Adjusted Consolidated Net Operating Loss (97.8) (92.9) (27.9) (27.0) Net Income (Loss) From: Change in Fair Value of Equity and Convertible Securities 5.5 (63.1) 2.3 (8.8) Net Realized Investment (Losses) Gains (30.3) 0.3 (22.9) (9.6) Impairment Gains (Losses) 0.1 (17.5) (0.8) (6.6) Acquisition and Disposition Related Transaction, Integration, Restructuring and Other Costs (80.5) (32.2) (34.2) (20.7) Debt Extinguishment, Pension Settlement and Other Charges (55.5) (2.9) (55.5) — Goodwill Impairment Charge (45.5) — — — Non-Core Operations (19.5) (25.0) (7.3) (2.1) Net Loss attributable to Kemper Corporation $ (323.5) $ (233.3) $ (146.3) $ (74.8) Net Loss Noncontrolling Interest (0.1) — (0.1) — Net Loss $ (323.6) $ (233.3) $ (146.4) $ (74.8)

Property and Casualty Insurance

Property and Casualty Insurance Reserves	9 Months Ended
	Sep. 30, 2023
Liability for Future Policy Benefits and Unpaid Claims and Claims Adjustment Expense [Abstract]
Property and Casualty Insurance Reserves	Property and Casualty Insurance Reserves Property and casualty insurance reserve activity for the nine months ended September 30, 2023 and 2022 was: Nine Months Ended (Dollars in Millions) Sep 30, Sep 30, Property and Casualty Insurance Reserves: Gross of Reinsurance at Beginning of Year $ 2,756.9 $ 2,772.7 Less Reinsurance Recoverables at Beginning of Year 39.6 41.9 Property and Casualty Insurance Reserves, Net of Reinsurance at Beginning of Year 2,717.3 2,730.8 Incurred Losses and Loss Adjustment Expenses (“ LAE”) Related to: Current Year 2,660.5 3,125.0 Prior Years 158.5 (22.5) Total Incurred Losses and LAE 2,819.0 3,102.5 Paid Losses and LAE Related to: Current Year 1,411.8 1,748.9 Prior Years 1,428.9 1,406.6 Total Paid Losses and LAE 2,840.7 3,155.5 Property and Casualty Insurance Reserves, Net of Reinsurance at End of Period 2,695.6 2,677.8 Plus Reinsurance Recoverables at End of Period 28.9 42.5 Property and Casualty Insurance Reserves, Gross of Reinsurance at End of Period $ 2,724.5 $ 2,720.3 Property and casualty insurance reserves are estimated based on historical experience patterns and current economic trends. Actual loss experience and loss trends are likely to differ from these historical experience patterns and economic conditions. Loss experience and loss trends emerge over several years from the dates of loss inception. The Company monitors such emerging loss trends on a quarterly basis. Changes in such estimates are included in the Condensed Consolidated Statements of Loss in the period of change. For the nine months ended September 30, 2023, the Company increased its property and casualty insurance reserves by $158.5 million to recognize adverse development of loss and LAE reserves from prior accident years. Specialty personal automobile insurance loss and LAE reserves developed adversely by $110.9 million due primarily to higher than expected emergence in loss patterns related to third and fourth accident quarters of 2022 within the bodily injury and physical damage coverages as well as an increase in Florida personal injury protection driven by higher than expected frequency and severity resulting from an increase in litigated claim activity, mainly from policy years 2020 through 2022. Commercial automobile insurance loss and LAE reserves developed adversely by $22.2 million due to higher than expected emergence in loss patterns related to policy years 2021 and 2022 bodily injury coverages. Non-Core personal automobile insurance loss and LAE reserves developed adversely by $18.3 million due to higher than expected emergence in loss patterns related to the third and fourth accident quarters of 2022 within the bodily injury and physical damage coverages. Non-Core homeowners loss and LAE reserves developed adversely by $3.8 million. None-Core other lines loss and LAE reserves developed adversely by $3.3 million. For the nine months ended September 30, 2022, the Company decreased its property and casualty insurance reserves by $22.5 million to recognize favorable development of loss and LAE reserves from prior accident years. Specialty personal automobile insurance loss and LAE reserves developed favorably by $31.6 million due primarily to the emergence of more favorable loss patterns than expected for liability and physical damage insurance. Commercial automobile insurance loss and LAE reserves developed adversely by $7.5 million due primarily to the emergence of more adverse loss patterns than expected for liability insurance. Non-Core personal automobile insurance loss and LAE reserves developed adversely by $1.9 million due primarily to the emergence of more adverse loss patterns than expected for liability insurance. Homeowners loss and LAE reserves developed favorably by $6.1 million due primarily to the emergence of more favorable loss patterns than expected. Other lines loss and LAE reserves developed adversely by $5.8 million due primarily to the emergence of more adverse loss patterns than expected for prior accident years. Note 6 - Property and Casualty Insurance Reserves (Continued) The Company cannot predict whether loss and LAE reserves will develop favorably or adversely from the amounts reported in the Company’s Condensed Consolidated Financial Statements. The Company believes that any such development will not have a material effect on the Company’s Condensed Consolidated Shareholders’ Equity, but could have a material effect on the Company’s consolidated financial results for a given period. Receivables from Policyholders - Allowance for Expected Credit Losses The following table presents receivables from policyholders, net of the allowance for expected credit losses including a roll forward of changes in the allowance for expected credit losses for the nine months ended September 30, 2023. (Dollars in Millions) Receivables from Policyholders, Net of Allowance for Expected Credit Losses Allowance for Expected Credit Losses Balance at Beginning of Year $ 1,286.6 $ 13.1 Provision for Expected Credit Losses 32.8 Write-offs of Uncollectible Receivables from Policyholders (32.4) Balance at End of Period $ 1,102.6 $ 13.5 The following table presents receivables from policyholders, net of the allowance for expected credit losses including a roll forward of changes in the allowance for expected credit losses for the nine months ended September 30, 2022. (Dollars in Millions) Receivables from Policyholders, Net of Allowance for Expected Credit Losses Allowance for Expected Credit Losses Balance at Beginning of Year $ 1,418.7 $ 13.6 Provision for Expected Credit Losses 36.7 Write-offs of Uncollectible Receivables from Policyholders (37.8) Balance at End of Period $ 1,349.1 $ 12.5 The following tables summarize balances and changes in the present value of expected net premiums, present value of expected future policyholder benefits and net liability for future policyholder benefits as of and for the nine and three months ended September 30, 2023 and September 30, 2022: Nine Months Ended Three Months Ended Sep 30, 2023 Sep 30, 2022 Sep 30, 2023 Sep 30, 2022 Present Value of Expected Net Premiums Balance, Beginning of Period $ 688.6 $ 669.0 $ 711.7 $ 646.4 Beginning Balance at Original Discount Rate $ 728.9 $ 599.8 $ 745.1 $ 660.3 Effect of Changes in Cash Flow Assumptions — — — — Effect of Actual Variances from Expected Experience (18.6) 5.2 (6.3) (8.3) Adjusted Beginning of Period Balance 710.3 605.0 738.8 652.0 Issuances 81.6 109.9 19.7 30.5 Interest Accrual 22.2 15.6 7.7 5.3 Net Premiums Collected (71.6) (66.0) (23.7) (23.3) Ending Balance at Original Discount Rate 742.5 664.5 742.5 664.5 Effect of Changes in Discount Rate Assumptions (56.1) (42.7) (56.1) (42.7) Balance, End of Period $ 686.4 $ 621.8 $ 686.4 $ 621.8 Present Value of Expected Future Policyholder Benefits Balance, Beginning of Period $ 3,561.0 $ 4,933.1 $ 3,635.9 $ 3,799.4 Beginning Balance at Original Discount Rate $ 3,906.2 $ 3,788.1 $ 3,915.1 $ 3,827.6 Effect of Changes in Cash Flow Assumptions — — — — Effect of Actual Variances From Expected Experience (21.7) 7.4 (8.5) (7.9) Adjusted Beginning of Period Balance 3,884.5 3,795.5 3,906.6 3,819.7 Issuances 80.8 110.0 18.9 30.5 Interest Accrual 128.2 122.1 43.0 40.7 Benefit Payments (184.4) (197.9) (59.4) (61.2) Ending Balance at Original Discount Rate 3,909.1 3,829.7 3,909.1 3,829.7 Effect of Changes in Discount Rate Assumptions (578.6) (387.8) (578.6) (387.8) Balance, End of Period $ 3,330.5 $ 3,441.9 $ 3,330.5 $ 3,441.9 Net Liability for Future Policyholder Benefits $ 2,644.1 $ 2,820.1 $ 2,644.1 $ 2,820.1 Less: Reinsurance Recoverable — — — — Net Liability for Future Policyholder Benefits, After Reinsurance Recoverable $ 2,644.1 $ 2,820.1 $ 2,644.1 $ 2,820.1 The weighted-average liability duration of the liability for future policyholder benefits as calculated under current rates is as follows: Sep 30, 2023 Sep 30, 2022 Weighted-Average Liability Duration of the Liability for Future Policyholder Benefits (Years) 13.8 15.5 Note 7 - Liability for Future Policyholder Benefits (Continued) The reconciliation of the net liability for future policyholder benefits to Life and Health Insurance Reserves in the Condensed Consolidated Balance Sheets is as follows: Sep 30, 2023 Sep 30, 2022 Net Liability for Future Policyholder Benefits 2,644.1 2,820.1 Deferred Profit Liability 304.9 249.9 Other 1 149.1 149.8 Total Life and Health Insurance Reserves $ 3,098.1 $ 3,219.8 1 Other primarily consists of Accident and Health and Universal Life reserves The amounts of expected undiscounted future benefit payments, expected undiscounted future gross premiums and expected discounted future gross premiums, were as follows: Sep 30, 2023 Sep 30, 2022 Expected Future Benefit Payments, undiscounted $ 10,181.5 $ 9,585.4 Expected Future Gross Premiums, undiscounted $ 4,446.4 $ 3,801.1 Expected Future Gross Premiums, discounted $ 2,748.0 $ 2,585.1 The amount of revenue and interest recognized in the Condensed Consolidated Statements of Loss is as follows: Nine Months Ended Three Months Ended Sep 30, 2023 Sep 30, 2022 Sep 30, 2023 Sep 30, 2022 Gross Premiums or Assessments $ 300.7 $ 297.2 $ 98.4 $ 100.8 Interest Expense $ 106.1 $ 106.5 $ 35.4 $ 35.4 The weighted-average interest rate is as follows: Sep 30, 2023 Sep 30, 2022 Interest Accretion Rate 4.57 % 4.59 % Current Discount Rate 5.88 % 5.44 % Significant assumption inputs to the calculation of the liability for future policyholder benefits include mortality, lapses, and discount rates (both accretion and current). The Company reviewed all significant assumptions and did not make any changes to mortality and lapse assumptions. Market data that underlies current discount rates was updated from June 30, 2023.

Financial Services, Insurance

Financial Services, Insurance	9 Months Ended
	Sep. 30, 2023
Insurance [Abstract]
Property and Casualty Insurance Reserves	Property and Casualty Insurance Reserves Property and casualty insurance reserve activity for the nine months ended September 30, 2023 and 2022 was: Nine Months Ended (Dollars in Millions) Sep 30, Sep 30, Property and Casualty Insurance Reserves: Gross of Reinsurance at Beginning of Year $ 2,756.9 $ 2,772.7 Less Reinsurance Recoverables at Beginning of Year 39.6 41.9 Property and Casualty Insurance Reserves, Net of Reinsurance at Beginning of Year 2,717.3 2,730.8 Incurred Losses and Loss Adjustment Expenses (“ LAE”) Related to: Current Year 2,660.5 3,125.0 Prior Years 158.5 (22.5) Total Incurred Losses and LAE 2,819.0 3,102.5 Paid Losses and LAE Related to: Current Year 1,411.8 1,748.9 Prior Years 1,428.9 1,406.6 Total Paid Losses and LAE 2,840.7 3,155.5 Property and Casualty Insurance Reserves, Net of Reinsurance at End of Period 2,695.6 2,677.8 Plus Reinsurance Recoverables at End of Period 28.9 42.5 Property and Casualty Insurance Reserves, Gross of Reinsurance at End of Period $ 2,724.5 $ 2,720.3 Property and casualty insurance reserves are estimated based on historical experience patterns and current economic trends. Actual loss experience and loss trends are likely to differ from these historical experience patterns and economic conditions. Loss experience and loss trends emerge over several years from the dates of loss inception. The Company monitors such emerging loss trends on a quarterly basis. Changes in such estimates are included in the Condensed Consolidated Statements of Loss in the period of change. For the nine months ended September 30, 2023, the Company increased its property and casualty insurance reserves by $158.5 million to recognize adverse development of loss and LAE reserves from prior accident years. Specialty personal automobile insurance loss and LAE reserves developed adversely by $110.9 million due primarily to higher than expected emergence in loss patterns related to third and fourth accident quarters of 2022 within the bodily injury and physical damage coverages as well as an increase in Florida personal injury protection driven by higher than expected frequency and severity resulting from an increase in litigated claim activity, mainly from policy years 2020 through 2022. Commercial automobile insurance loss and LAE reserves developed adversely by $22.2 million due to higher than expected emergence in loss patterns related to policy years 2021 and 2022 bodily injury coverages. Non-Core personal automobile insurance loss and LAE reserves developed adversely by $18.3 million due to higher than expected emergence in loss patterns related to the third and fourth accident quarters of 2022 within the bodily injury and physical damage coverages. Non-Core homeowners loss and LAE reserves developed adversely by $3.8 million. None-Core other lines loss and LAE reserves developed adversely by $3.3 million. For the nine months ended September 30, 2022, the Company decreased its property and casualty insurance reserves by $22.5 million to recognize favorable development of loss and LAE reserves from prior accident years. Specialty personal automobile insurance loss and LAE reserves developed favorably by $31.6 million due primarily to the emergence of more favorable loss patterns than expected for liability and physical damage insurance. Commercial automobile insurance loss and LAE reserves developed adversely by $7.5 million due primarily to the emergence of more adverse loss patterns than expected for liability insurance. Non-Core personal automobile insurance loss and LAE reserves developed adversely by $1.9 million due primarily to the emergence of more adverse loss patterns than expected for liability insurance. Homeowners loss and LAE reserves developed favorably by $6.1 million due primarily to the emergence of more favorable loss patterns than expected. Other lines loss and LAE reserves developed adversely by $5.8 million due primarily to the emergence of more adverse loss patterns than expected for prior accident years. Note 6 - Property and Casualty Insurance Reserves (Continued) The Company cannot predict whether loss and LAE reserves will develop favorably or adversely from the amounts reported in the Company’s Condensed Consolidated Financial Statements. The Company believes that any such development will not have a material effect on the Company’s Condensed Consolidated Shareholders’ Equity, but could have a material effect on the Company’s consolidated financial results for a given period. Receivables from Policyholders - Allowance for Expected Credit Losses The following table presents receivables from policyholders, net of the allowance for expected credit losses including a roll forward of changes in the allowance for expected credit losses for the nine months ended September 30, 2023. (Dollars in Millions) Receivables from Policyholders, Net of Allowance for Expected Credit Losses Allowance for Expected Credit Losses Balance at Beginning of Year $ 1,286.6 $ 13.1 Provision for Expected Credit Losses 32.8 Write-offs of Uncollectible Receivables from Policyholders (32.4) Balance at End of Period $ 1,102.6 $ 13.5 The following table presents receivables from policyholders, net of the allowance for expected credit losses including a roll forward of changes in the allowance for expected credit losses for the nine months ended September 30, 2022. (Dollars in Millions) Receivables from Policyholders, Net of Allowance for Expected Credit Losses Allowance for Expected Credit Losses Balance at Beginning of Year $ 1,418.7 $ 13.6 Provision for Expected Credit Losses 36.7 Write-offs of Uncollectible Receivables from Policyholders (37.8) Balance at End of Period $ 1,349.1 $ 12.5 The following tables summarize balances and changes in the present value of expected net premiums, present value of expected future policyholder benefits and net liability for future policyholder benefits as of and for the nine and three months ended September 30, 2023 and September 30, 2022: Nine Months Ended Three Months Ended Sep 30, 2023 Sep 30, 2022 Sep 30, 2023 Sep 30, 2022 Present Value of Expected Net Premiums Balance, Beginning of Period $ 688.6 $ 669.0 $ 711.7 $ 646.4 Beginning Balance at Original Discount Rate $ 728.9 $ 599.8 $ 745.1 $ 660.3 Effect of Changes in Cash Flow Assumptions — — — — Effect of Actual Variances from Expected Experience (18.6) 5.2 (6.3) (8.3) Adjusted Beginning of Period Balance 710.3 605.0 738.8 652.0 Issuances 81.6 109.9 19.7 30.5 Interest Accrual 22.2 15.6 7.7 5.3 Net Premiums Collected (71.6) (66.0) (23.7) (23.3) Ending Balance at Original Discount Rate 742.5 664.5 742.5 664.5 Effect of Changes in Discount Rate Assumptions (56.1) (42.7) (56.1) (42.7) Balance, End of Period $ 686.4 $ 621.8 $ 686.4 $ 621.8 Present Value of Expected Future Policyholder Benefits Balance, Beginning of Period $ 3,561.0 $ 4,933.1 $ 3,635.9 $ 3,799.4 Beginning Balance at Original Discount Rate $ 3,906.2 $ 3,788.1 $ 3,915.1 $ 3,827.6 Effect of Changes in Cash Flow Assumptions — — — — Effect of Actual Variances From Expected Experience (21.7) 7.4 (8.5) (7.9) Adjusted Beginning of Period Balance 3,884.5 3,795.5 3,906.6 3,819.7 Issuances 80.8 110.0 18.9 30.5 Interest Accrual 128.2 122.1 43.0 40.7 Benefit Payments (184.4) (197.9) (59.4) (61.2) Ending Balance at Original Discount Rate 3,909.1 3,829.7 3,909.1 3,829.7 Effect of Changes in Discount Rate Assumptions (578.6) (387.8) (578.6) (387.8) Balance, End of Period $ 3,330.5 $ 3,441.9 $ 3,330.5 $ 3,441.9 Net Liability for Future Policyholder Benefits $ 2,644.1 $ 2,820.1 $ 2,644.1 $ 2,820.1 Less: Reinsurance Recoverable — — — — Net Liability for Future Policyholder Benefits, After Reinsurance Recoverable $ 2,644.1 $ 2,820.1 $ 2,644.1 $ 2,820.1 The weighted-average liability duration of the liability for future policyholder benefits as calculated under current rates is as follows: Sep 30, 2023 Sep 30, 2022 Weighted-Average Liability Duration of the Liability for Future Policyholder Benefits (Years) 13.8 15.5 Note 7 - Liability for Future Policyholder Benefits (Continued) The reconciliation of the net liability for future policyholder benefits to Life and Health Insurance Reserves in the Condensed Consolidated Balance Sheets is as follows: Sep 30, 2023 Sep 30, 2022 Net Liability for Future Policyholder Benefits 2,644.1 2,820.1 Deferred Profit Liability 304.9 249.9 Other 1 149.1 149.8 Total Life and Health Insurance Reserves $ 3,098.1 $ 3,219.8 1 Other primarily consists of Accident and Health and Universal Life reserves The amounts of expected undiscounted future benefit payments, expected undiscounted future gross premiums and expected discounted future gross premiums, were as follows: Sep 30, 2023 Sep 30, 2022 Expected Future Benefit Payments, undiscounted $ 10,181.5 $ 9,585.4 Expected Future Gross Premiums, undiscounted $ 4,446.4 $ 3,801.1 Expected Future Gross Premiums, discounted $ 2,748.0 $ 2,585.1 The amount of revenue and interest recognized in the Condensed Consolidated Statements of Loss is as follows: Nine Months Ended Three Months Ended Sep 30, 2023 Sep 30, 2022 Sep 30, 2023 Sep 30, 2022 Gross Premiums or Assessments $ 300.7 $ 297.2 $ 98.4 $ 100.8 Interest Expense $ 106.1 $ 106.5 $ 35.4 $ 35.4 The weighted-average interest rate is as follows: Sep 30, 2023 Sep 30, 2022 Interest Accretion Rate 4.57 % 4.59 % Current Discount Rate 5.88 % 5.44 % Significant assumption inputs to the calculation of the liability for future policyholder benefits include mortality, lapses, and discount rates (both accretion and current). The Company reviewed all significant assumptions and did not make any changes to mortality and lapse assumptions. Market data that underlies current discount rates was updated from June 30, 2023.

Deferred Costs, Capitalized, Pr

Deferred Costs, Capitalized, Prepaid, and Other Assets	9 Months Ended
	Sep. 30, 2023
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Deferred Policy Acquisition Costs	Deferred Policy Acquisition Costs The following table presents the balances and changes in Deferred Policy Acquisition Costs for the Property and Casualty and Life and Health and business for the nine months ended September 30, 2023 and 2022: Sep 30, 2023 Sep 30, 2022 Property and Casualty Life and Health Total Property and Casualty Life and Health Total Balance, Beginning of Year $ 231.1 $ 404.5 $ 635.6 $ 268.7 $ 419.3 $ 688.0 Capitalizations 407.1 42.2 449.3 483.0 47.0 530.0 Amortization Expense (439.1) (14.7) (453.8) (507.2) (21.5) (528.7) Experience Adjustment — (8.9) (8.9) — (5.5) (5.5) Balance 199.1 423.1 622.2 244.5 439.3 683.8 Less: Deferred Policy Acquisition Costs Asset Held-for-Sale — — — — 38.7 38.7 Balance, End of Period $ 199.1 $ 423.1 $ 622.2 $ 244.5 $ 400.6 $ 645.1 Costs directly associated with the successful acquisition of business, principally commissions and certain premium taxes and policy issuance costs, are deferred. Costs deferred on property and casualty insurance contracts are amortized over the period in which premiums are earned. Costs deferred on traditional life insurance products and other long-duration insurance contracts are amortized on a constant level basis over the expected life of the contracts in accordance with the assumptions used to estimate the liability for future policyholder benefits for nonparticipating traditional and limited-payment contracts. The underlying assumptions for deferred policy acquisition costs and the liability for future policyholder benefits were updated concurrently. The Company did not make any changes to future assumptions for both the nine months ended September 30, 2023 and 2022.

Investments

Investments	9 Months Ended
	Sep. 30, 2023
Investments, Debt and Equity Securities [Abstract]
Investments	Note 9 - Investments Fixed Maturities The amortized cost and fair values of the Company’s Investments in Fixed Maturities at September 30, 2023 were: Amortized Gross Unrealized Allowance for Expected Credit Losses Fair Value (Dollars in Millions) Gains Losses U.S. Government and Government Agencies and Authorities $ 599.7 $ 0.2 $ (112.7) $ — $ 487.2 States and Political Subdivisions 1,613.9 1.5 (294.7) (0.5) 1,320.2 Foreign Governments 5.1 — (0.9) — 4.2 Corporate Securities: Bonds and Notes 4,047.3 6.8 (651.6) (8.1) 3,394.4 Redeemable Preferred Stocks 9.0 0.1 (1.3) — 7.8 Collateralized Loan Obligations 985.4 0.9 (30.1) — 956.2 Other Mortgage- and Asset-backed 362.1 0.1 (57.7) — 304.5 Investments in Fixed Maturities $ 7,622.5 $ 9.6 $ (1,149.0) $ (8.6) $ 6,474.5 The amortized cost and fair values of the Company’s Investments in Fixed Maturities at December 31, 2022 were: Amortized Gross Unrealized Allowance for Expected Credit Losses Fair Value (Dollars in Millions) Gains Losses U.S. Government and Government Agencies and Authorities $ 612.5 $ 1.3 $ (85.8) $ — $ 528.0 States and Political Subdivisions 1,797.6 10.3 (238.3) (0.7) 1,568.9 Foreign Governments 5.0 — (0.9) — 4.1 Corporate Securities: Bonds and Notes 4,030.3 17.7 (499.7) (8.9) 3,539.4 Redeemable Preferred Stocks 9.0 — (1.0) — 8.0 Collateralized Loan Obligations 1,014.7 — (60.8) — 953.9 Other Mortgage- and Asset-backed 342.7 0.1 (50.3) — 292.5 Investments in Fixed Maturities $ 7,811.8 $ 29.4 $ (936.8) $ (9.6) $ 6,894.8 Other Receivables included $0.9 million and $5.8 million of unsettled sales of Investments in Fixed Maturities at September 30, 2023 and December 31, 2022, respectively. Accrued Expenses and Other Liabilities included unsettled purchases of Investments in Fixed Maturities of $1.0 million and $25.9 million at September 30, 2023 and December 31, 2022, respectively. Note 9 - Investments (Continued) The amortized cost and fair values of the Company’s Investments in Fixed Maturities at September 30, 2023 by contractual maturity were: (Dollars in Millions) Amortized Cost Fair Value Due in One Year or Less $ 170.8 $ 161.3 Due after One Year to Five Years 915.2 872.0 Due after Five Years to Ten Years 1,089.5 906.1 Due after Ten Years 3,625.5 2,898.1 Mortgage- and Asset-backed Securities Not Due at a Single Maturity Date 1,821.5 1,637.0 Investments in Fixed Maturities $ 7,622.5 $ 6,474.5 The expected maturities of the Company’s Investments in Fixed Maturities may differ from the contractual maturities because issuers may have the right to call or prepay obligations with or without call or prepayment penalties. Investments in Mortgage- and Asset-backed Securities Not Due at a Single Maturity Date at September 30, 2023 consisted of securities issued by the Government National Mortgage Association with a fair value of $231.3 million, securities issued by the Federal National Mortgage Association with a fair value of $85.9 million, securities issued by the Federal Home Loan Mortgage Corporation with a fair value of $59.2 million, and securities issued by other non-governmental issuers with a fair value of $1,260.6 million. An aging of unrealized losses on the Company’s Investments in Fixed Maturities at September 30, 2023 is presented below. Less Than 12 Months 12 Months or Longer Total (Dollars in Millions) Fair Unrealized Fair Unrealized Fair Unrealized Fixed Maturities: U.S. Government and Government Agencies and Authorities $ 93.4 $ (4.1) $ 381.9 $ (108.6) $ 475.3 $ (112.7) States and Political Subdivisions 374.3 (22.0) 873.5 (272.7) 1,247.8 (294.7) Foreign Governments 0.1 — 2.4 (0.9) 2.5 (0.9) Corporate Securities: Bonds and Notes 608.6 (54.1) 2,638.0 (597.5) 3,246.6 (651.6) Redeemable Preferred Stocks — — 7.4 (1.3) 7.4 (1.3) Collateralized Loan Obligations 21.9 (0.3) 776.2 (29.8) 798.1 (30.1) Other Mortgage- and Asset-backed 25.3 (0.4) 276.5 (57.3) 301.8 (57.7) Total Fixed Maturities $ 1,123.6 $ (80.9) $ 4,955.9 $ (1,068.1) $ 6,079.5 $ (1,149.0) Investment-grade fixed maturity investments comprised $1,120.1 million and below-investment-grade Fixed Maturity Investments comprised $28.9 million of the unrealized losses on investments in fixed maturities at September 30, 2023. For below-investment-grade fixed maturity investments in an unrealized loss position, the unrealized loss amount, on average, was approximately 9.4% of the amortized cost basis of the investment. Note 9 - Investments (Continued) An aging of unrealized losses on the Company’s Investments in Fixed Maturities at December 31, 2022 is presented below. Less Than 12 Months 12 Months or Longer Total (Dollars in Millions) Fair Unrealized Fair Unrealized Fair Unrealized Fixed Maturities: U.S. Government and Government Agencies and Authorities $ 337.3 $ (49.3) $ 126.5 $ (36.5) $ 463.8 $ (85.8) States and Political Subdivisions 854.7 (140.6) 276.8 (97.7) 1,131.5 (238.3) Foreign Governments 0.1 — 2.6 (0.9) 2.7 (0.9) Corporate Securities: Bonds and Notes 2,730.6 (373.9) 424.4 (125.8) 3,155.0 (499.7) Redeemable Preferred Stocks 7.7 (1.0) — — 7.7 (1.0) Collateralized Loan Obligations 568.2 (34.2) 373.9 (26.6) 942.1 (60.8) Other Mortgage- and Asset-backed 205.4 (28.9) 79.5 (21.4) 284.9 (50.3) Total Fixed Maturities $ 4,704.0 $ (627.9) $ 1,283.7 $ (308.9) $ 5,987.7 $ (936.8) Investment-grade fixed maturity investments comprised $904.0 million and below-investment-grade Fixed Maturity Investments comprised $32.8 million of the unrealized losses on Investments in Fixed Maturities at December 31, 2022. For below-investment-grade fixed maturity investments in an unrealized loss position, the unrealized loss amount, on average, was approximately 11% of the amortized cost basis of the investment. Fixed Maturities - Expected Credit Losses The following table sets forth the change in allowance for credit losses on fixed maturities available-for-sale by major security type for nine months ended September 30, 2023. States and Political Subdivisions Corporate Bonds and Notes Total (Dollars in Millions) Beginning of the Year $ 0.7 $ 8.9 $ 9.6 Additions for Securities for which No Previous Expected Credit Losses were — 2.2 2.2 Reduction Due to Sales (0.3) (1.9) (2.2) Net Increase (Decrease) in Allowance on Securities for which Expected Credit Losses were Previously Recognized 0.1 (1.1) (1.0) Write-offs Charged Against Allowance — — — End of the Period $ 0.5 $ 8.1 $ 8.6 Note 9 - Investments (Continued) The following table sets forth the change in allowance for credit losses on fixed maturities available-for-sale by major security type for the nine months ended September 30, 2022. States and Political Subdivisions Corporate Bonds and Notes Total (Dollars in Millions) Beginning of the Year $ — $ 7.5 $ 7.5 Additions for Securities for which No Previous Expected Credit Losses were 0.4 5.2 5.6 Net Increase in Allowance on Securities for which Expected Credit Losses were Previously Recognized — 5.1 5.1 Write-offs Charged Against Allowance — (10.7) (10.7) End of the Period $ 0.4 $ 7.1 $ 7.5 Equity Securities at Fair Value Investments in Equity Securities at Fair Value were $233.4 million and $243.2 million at September 30, 2023 and December 31, 2022, respectively. Net unrealized gains arising during the nine months ended September 30, 2023 and recognized in earnings, related to such investments still held as of September 30, 2023, were $5.1 million. There were no unsettled purchases of Investments in Equity Securities at Fair Value at September 30, 2023 or December 31, 2022. There were $20.7 million and $0.0 million in unsettled sales of Investments in Equity Securities at Fair Value at September 30, 2023 and December 31, 2022, respectively. Equity Method Limited Liability Investments Equity Method Limited Liability Investments include investments in limited liability investment companies and limited partnerships in which the Company’s interests are not deemed minor and are accounted for under the equity method of accounting. The Company’s investments in Equity Method Limited Liability Investments are generally of a passive nature in that the Company does not take an active role in the management of the investment entity. The Company’s maximum exposure to loss at September 30, 2023 is limited to the total carrying value of $224.1 million. In addition, the Company had outstanding commitments totaling approximately $89.4 million to fund Equity Method Limited Liability Investments at September 30, 2023. At September 30, 2023, 2.5% of Equity Method Limited Liability Investments were reported without a reporting lag. Of the total carrying value, 5.5% was reported with a one month lag and the remainder was reported with more than a one-month lag. There were no unsettled purchases of Equity Method Limited Liability Investments at September 30, 2023 or December 31, 2022. There were $2.1 million and $35.2 million unsettled sales of Equity Method Limited Liability Investments at September 30, 2023 and December 31, 2022, respectively. Unsettled sales of Equity Method Limited Liability Investments are carried within Other Receivables on the Condensed Consolidated Balance Sheets. Alternative Energy Partnership Investments Alternative Energy Partnership Investments include partnerships formed to invest in newly installed residential solar leases and power purchase agreements. As a result of this investment, the Company has the right to certain investment tax credits and tax depreciation benefits, and to a lesser extent, cash flows generated from the installed solar systems leased to individual consumers for a fixed period of time. The Hypothetical Liquidation Book Value (“HLBV”) equity method of accounting is used for the Company’s investments in Alternative Energy Partnership Investments. The Company’s maximum exposure to loss at September 30, 2023 is limited to the total carrying value of $17.2 million. The Company had no outstanding commitments to fund Alternative Energy Partnership Investments as of September 30, 2023. Alternative Energy Partnership Investments are reported on a three-month lag. Note 9 - Investments (Continued) Loans to Policyholders Loans to Policyholders represents funds loaned to policyholders up to the cash surrender value of the associated insurance policies and are carried at the unpaid principal balances due to the Company from the policyholders. Interest income on policy loans is recognized in Net Investment Income at the contract interest rate when earned. Policy loans are fully collateralized by the cash surrender value of the associated insurance policies. The carrying values of the Company’s Loans to Policyholders at Unpaid Principal investment at September 30, 2023 and December 31, 2022 were $281.8 million and $283.4 million, respectively. Other Investments The carrying values of the Company’s Other Investments at September 30, 2023 and December 31, 2022 were: (Dollars in Millions) Sep 30, Dec 31, Equity Securities at Modified Cost $ 33.1 $ 38.4 Convertible Securities at Fair Value 45.9 43.3 Real Estate at Depreciated Cost 95.4 93.6 Mortgage Loans 98.5 91.1 Other 0.2 3.5 Total $ 273.1 $ 269.9 The Company performs a qualitative impairment analysis of its Other Investments on a quarterly basis consisting of various factors such as earnings performance, current market conditions, changes in credit ratings, changes in the regulatory environment and other factors. If the qualitative analysis identifies the presence of impairment indicators, the Company estimates the fair value of the investment. If the estimated fair value is below the carrying value, the Company records an impairment in the Condensed Consolidated Statements of Loss to reduce the carrying value to the estimated fair value. When the Company identifies observable transactions of the same or similar securities to those held by the Company, the Company increases or decreases the carrying value to the observable transaction price. The Company did not recognize any changes in carrying value due to observable transactions for the nine months ended September 30, 2023. The Company did not recognize any impairment on Equity Securities at Modified Cost for nine months ended September 30, 2023 as a result of the Company’s impairment analysis. The Company recognized no cumulative increases or decreases in the carrying value due to observable transactions and $7.5 million of cumulative impairments on Equity Securities at Modified Cost held as of September 30, 2023. Note 9 - Investments (Continued) Net Investment Income Net Investment Income for the nine and three months ended September 30, 2023 and 2022 was: Nine Months Ended Three Months Ended (Dollars in Millions) Sep 30, Sep 30, Sep 30, Sep 30, Investment Income: Interest on Fixed Income Securities $ 259.8 $ 218.4 $ 86.5 $ 76.9 Dividends on Equity Securities Excluding Alternative Investments 3.4 4.3 1.2 1.1 Alternative Investments: Equity Method Limited Liability Investments 8.2 28.0 4.3 (0.6) Limited Liability Investments Included in Equity Securities 14.3 34.9 5.4 8.8 Total Alternative Investments 22.5 62.9 9.7 8.2 Short-term Investments 11.9 1.4 6.0 1.1 Loans to Policyholders 15.6 16.3 5.1 5.5 Real Estate 6.6 7.6 2.3 3.1 Company-Owned Life Insurance 22.6 28.0 6.4 9.9 Other 10.1 5.1 1.8 1.7 Total Investment Income 352.5 344.0 119.0 107.5 Investment Expenses: Real Estate 6.0 5.8 1.7 2.3 Other Investment Expenses 31.4 21.9 10.3 7.4 Total Investment Expenses 37.4 27.7 12.0 9.7 Net Investment Income $ 315.1 $ 316.3 $ 107.0 $ 97.8 Gross gains and losses on sales of investments in fixed maturities and gains and losses associated with Ultra-Long Treasury Futures for the nine and three months ended September 30, 2023 and 2022 were: Nine Months Ended Three Months Ended (Dollars in Millions) Sep 30, Sep 30, Sep 30, Sep 30, Fixed Maturities: Gains on Sales $ 2.3 $ 28.0 $ 0.8 $ 14.2 Losses on Sales (10.5) (27.5) (1.2) (23.9) (Losses) Gains on Hedging Activity (29.7) — (29.4) (0.3)

Derivative Instruments and Hedg

Derivative Instruments and Hedging Activities	9 Months Ended
	Sep. 30, 2023
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Instruments and Hedging Activities Disclosure	Note 10 - Derivatives The Company’s earnings, cash flows, and financial position are subject to fluctuations due to changes in prevailing interest rates. The Company entered into derivative agreements with maturity dates throughout 2023. Derivative instruments are carried at fair value on the Condensed Consolidated Balance Sheets. Derivative instruments in a gain position are presented within Other Investments and those in a loss position are included in Accrued Expenses and Other Liabilities. Changes in the fair values of derivatives are recorded on the Condensed Consolidated Statements of Loss within Net Realized Investment Gains or Accumulated Other Comprehensive Loss along with the corresponding change in the designated hedge assets. As of September 30, 2023, no derivatives qualified for hedge accounting, therefore, amounts previously held in Accumulated Other Comprehensive Loss have been recognized through the Condensed Consolidated Statements of Loss. Note 10 - Derivatives (Continued) Interest Rate Risk The Company’s debt securities valuations utilize the Treasury designated benchmark rate, exposing the Company to variability due to changes in interest rates. Interest Swap Lock The Company entered into an interest swap lock agreement in the third quarter of 2022 classified as cash flow hedges to manage exposure to changes in future purchase prices of fixed maturity securities attributable to changes in the benchmark (Treasury) interest rate. The Company assesses the effectiveness of cash flow hedges using the hypothetical derivative method. Based on the results of the assessment, the hedge was determined to be effective. The interest swap lock agreement was closed out in the first quarter of 2023. Ultra-Long Treasury Futures During 2023, the Company entered into two transactions of exchange-traded ultra-long Treasury futures (“Treasury Futures”) in order to manage exposure to upcoming changes in the benchmark (Treasury) interest rate of forecasted transactions. These derivatives expire quarterly. The Treasury Futures renewed in the third quarter of 2023. The open treasury futures do not qualify for hedge accounting. The results are shown in the Primary Risks Managed by Derivatives section below. Reverse Treasury Lock During 2022, the Company entered into a Reverse Treasury Lock agreement to manage reinvestment risk on future purchases of fixed maturity securities. The Reverse Treasury Lock agreement did not qualify for hedge accounting and matured in the first quarter of 2023. The results are shown in the Primary Risks Managed by Derivatives section below. Primary Risks Managed by Derivatives The following table presents the derivative instruments, primary underlying risk exposure, gross notional amount, and fair value of the Company’s derivatives: September 30, 2023 December 31, 2022 (Dollars in Millions) Fair Value Fair Value Derivative Instrument Primary Underlying Risk Exposure Gross Notional Amount Assets Liabilities Gross Notional Amount Assets Liabilities Derivatives Designated as Hedging Instruments: Interest Swap Lock Interest Rate Risk $ — $ — $ — $ 5.0 $ — $ 0.4 Derivatives Not Designated or Not Qualifying as Hedging Instruments: Treasury Futures Interest Rate Risk $ 202.5 $ — $ 15.6 $ — $ — $ — Reverse Treasury Lock Interest Rate Risk $ — $ — $ — $ 100.0 $ 1.7 $ —

Fair Value Measurements

Fair Value Measurements	9 Months Ended
	Sep. 30, 2023
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value MeasurementsThe Company classifies its Investments in Fixed Maturities as available-for-sale and reports these investments at fair value. The Company reports equity investments with readily determinable fair values as Equity Securities at Fair Value. Certain investments that are measured at fair value using the net asset value practical expedient are not required to be classified using the fair value hierarchy, but are presented in the following two tables to permit reconciliation of the fair value hierarchy to the amounts presented in the Condensed Consolidated Balance Sheets. Note 11 - Fair Value Measurements (Continued) The valuation of assets and liabilities measured at fair value in Company’s Condensed Consolidated Balance Sheets at September 30, 2023 is summarized below. Fair Value Measurements (Dollars in Millions) Quoted Prices Significant Other Significant Measured at Net Asset Value Total Fair Value Assets: Fixed Maturities: U.S. Government and Government Agencies and Authorities $ 94.4 $ 392.8 $ — $ — $ 487.2 States and Political Subdivisions — 1,320.1 0.1 — 1,320.2 Foreign Governments — 4.2 — — 4.2 Corporate Securities: Bonds and Notes — 3,212.0 182.4 — 3,394.4 Redeemable Preferred Stock — 1.2 6.6 — 7.8 Collateralized Loan Obligations — 956.2 — — 956.2 Other Mortgage and Asset-backed — 299.7 4.8 — 304.5 Total Investments in Fixed Maturities 94.4 6,186.2 193.9 — 6,474.5 Equity Securities at Fair Value: Preferred Stocks: Finance, Insurance and Real Estate — 19.9 — — 19.9 Other Industries — 8.4 3.3 — 11.7 Common Stocks: Finance, Insurance and Real Estate 0.6 — — — 0.6 Other Industries 0.2 — 0.4 — 0.6 Other Equity Interests: Exchange Traded Funds 7.1 — — — 7.1 Limited Liability Companies and Limited Partnerships — — — 193.5 193.5 Total Investments in Equity Securities at Fair Value 7.9 28.3 3.7 193.5 233.4 Other Investments: Convertible Securities at Fair Value — 45.9 — — 45.9 Total Assets $ 102.3 $ 6,260.4 $ 197.6 $ 193.5 $ 6,753.8 Liabilities: Accrued Expenses and Other Liabilities: Derivative Instruments Not Designated as Cash Flow Hedges $ — $ 15.6 $ — $ — $ 15.6 Total Liabilities $ — $ 15.6 $ — $ — $ 15.6 At September 30, 2023, the Company had unfunded commitments to invest an additional $103.3 million in certain limited liability investment companies and limited partnerships that will be included in Other Equity Interests if funded. Note 11 - Fair Value Measurements (Continued) The valuation of assets measured at fair value in the Company’s Consolidated Balance Sheets at December 31, 2022 is summarized below. Fair Value Measurements (Dollars in Millions) Quoted Prices Significant Other Significant Measured at Net Asset Value Total Fair Value Assets: Fixed Maturities: U.S. Government and Government Agencies and Authorities $ 103.6 $ 424.4 $ — $ — $ 528.0 States and Political Subdivisions — 1,568.9 — — 1,568.9 Foreign Governments — 4.1 — — 4.1 Corporate Securities: Bonds and Notes — 3,323.4 216.0 — 3,539.4 Redeemable Preferred Stocks — 1.2 6.8 — 8.0 Collateralized Loan Obligations — 953.9 — — 953.9 Other Mortgage and Asset-backed — 287.4 5.1 — 292.5 Total Investments in Fixed Maturities 103.6 6,563.3 227.9 — 6,894.8 Equity Securities at Fair Value: Preferred Stocks: Finance, Insurance and Real Estate — 29.0 — — 29.0 Other Industries — 9.2 1.6 — 10.8 Common Stocks: Finance, Insurance and Real Estate 0.9 — — — 0.9 Other Industries 0.3 0.4 0.5 — 1.2 Other Equity Interests: Exchange Traded Funds 12.2 — — — 12.2 Limited Liability Companies and Limited Partnerships — — — 189.1 189.1 Total Investments in Equity Securities at Fair Value 13.4 38.6 2.1 189.1 243.2 Other Investments: Convertible Securities at Fair Value — 43.3 — — 43.3 Other Assets: Derivative Instruments Not Designated as Hedges — 1.7 — — 1.7 Total Assets $ 117.0 $ 6,646.9 $ 230.0 $ 189.1 $ 7,183.0 Liabilities: Accrued Expenses and Other Liabilities: Derivative Instruments Designated as Fair Value Hedges $ — $ (0.4) $ — $ — $ (0.4) Total Liabilities $ — $ (0.4) $ — $ — $ (0.4) Note 11 - Fair Value Measurements (Continued) The Company’s investments in Fixed Maturities that are classified as Level 1 primarily consist of U.S. Treasury Bonds and Notes. The Company’s investments in Equity Securities at Fair Value that are classified as Level 1 consist of either investments in publicly-traded common stocks or exchange traded funds. The Company’s investments in Fixed Maturities that are classified as Level 2 primarily consist of investments in corporate bonds, obligations of states and political subdivisions, collateralized loan obligations, and mortgage-backed securities of U.S. government agencies. The Company’s investments in Equity Securities at Fair Value that are classified as Level 2 primarily consist of investments in preferred stocks. The Company’s Derivative Instruments Designated as Fair Value Hedges that are classified as Level 2 primarily consist of hedges against the Company’s available for sale debt securities portfolio. The Company uses a leading, nationally recognized provider of market data and analytics to price the vast majority of the Company’s Level 2 measurements. The provider utilizes evaluated pricing models that vary by asset class and incorporate available trade, bid and other market information. Because many fixed maturity securities do not trade on a daily basis, the provider’s evaluated pricing applications apply available information through processes such as benchmark curves, benchmarking of like securities, sector groupings and matrix pricing to prepare evaluations. In addition, the provider uses model processes to develop prepayment and interest rate scenarios. The pricing provider’s models and processes also take into account market convention. For each asset class, teams of its evaluators gather information from market sources and integrate relevant credit information, perceived market movements and sector news into the evaluated pricing applications and models. The Company generally validates the measurements obtained from its primary pricing provider by comparing them with measurements obtained from one additional pricing provider that provides either prices from recent market transactions, quotes in inactive markets or evaluations based on its own proprietary models. The Company investigates significant differences related to the values provided. On completion of its investigation, management exercises judgment to determine the price selected and whether adjustments, if any, to the price obtained from the Company’s primary pricing provider would warrant classification of the price as Level 3. In instances where a measurement cannot be obtained from either pricing provider, the Company generally will evaluate bid prices from one or more binding quotes obtained from market makers to value investments in inactive markets and classified by the Company as Level 2. The Company generally classifies securities when it receives non-binding quotes or indications as Level 3 securities unless the Company can validate the quote or indication against recent transactions in the market. The table below presents quantitative information about the significant unobservable inputs utilized by the Company in determining fair values for fixed maturity investments classified as Level 3 at September 30, 2023. (Dollars in Millions) Unobservable Input Total Fair Value Range of Unobservable Inputs Weighted-average Yield Investment-grade Market Yield $ 58.7 4.2 % - 16.4 % 9.6 % Non-investment-grade: Senior Debt Market Yield 41.9 11.0 - 36.7 13.8 Junior Debt Market Yield 32.2 12.4 - 22.5 14.6 Other Various 61.1 Total Level 3 Fixed Maturity Investments $ 193.9 The table below presents quantitative information about the significant unobservable inputs utilized by the Company in determining fair values for fixed maturity investments classified as Level 3 at December 31, 2022. (Dollars in Millions) Unobservable Input Total Fair Value Range of Unobservable Inputs Weighted-average Yield Investment-grade Market Yield $ 56.5 4.6 % - 14.5 % 9.2 % Non-investment-grade: Senior Debt Market Yield 72.9 4.6 - 36.7 10.9 Junior Debt Market Yield 42.1 8.8 - 22.5 15.1 Other Various 56.4 Total Level 3 Fixed Maturity Investments $ 227.9 Note 11 - Fair Value Measurements (Continued) For an investment in a fixed maturity security, an increase in the yield used to determine the fair value of the security will decrease the fair value of the security. A decrease in the yield used to determine fair value will increase the fair value of the security, but for callable securities the fair value increase is generally limited to par, unless security is currently callable at a premium. Information by security type pertaining to the changes in the fair value of the Company’s investments classified as Level 3 for the nine months ended September 30, 2023 is presented below. Fixed Maturities Equity Securities (Dollars in Millions) Corporate States and Political Sub- divisions Redeemable Other Mortgage- Preferred Total Balance at Beginning of Year $ 216.0 $ — $ 6.8 $ 5.1 $ 2.1 $ 230.0 Total Gains (Losses): Included in Condensed Consolidated Statements of Loss 0.7 — — — 0.1 0.8 Included in Other Comprehensive Income 0.2 — (0.2) (0.3) — (0.3) Purchases 44.0 0.1 — — 1.1 45.2 Settlements — — — — — — Sales (83.4) — — — — (83.4) Transfers into Level 3 5.0 — — — 0.4 5.4 Transfers out of Level 3 (0.1) — — — — (0.1) Balance at End of Period $ 182.4 $ 0.1 $ 6.6 $ 4.8 $ 3.7 $ 197.6 The transfers into and out of Level 3 were due primarily to changes in the availability of market observable inputs. Information by security type pertaining to the changes in the fair value of the Company’s investments classified as Level 3 for the three months ended September 30, 2023 is presented below. Fixed Maturities Equity Securities (Dollars in Millions) Corporate States and Political Sub- divisions Redeemable Other Mortgage- Preferred Total Balance at Beginning of Period $ 187.4 $ — $ 6.7 $ 5.2 $ 2.2 $ 201.5 Total Gains (Losses): Included in Condensed Consolidated Statements of Loss 0.2 — — — 1.5 1.7 Included in Other Comprehensive Income (2.2) — (0.1) (0.4) — (2.7) Purchases 6.1 0.1 — — — 6.2 Settlements — — — — — — Sales (14.1) — — — — (14.1) Transfers into Level 3 5.0 — — — — 5.0 Transfers out of Level 3 — — — — — — Balance at End of Period $ 182.4 $ 0.1 $ 6.6 $ 4.8 $ 3.7 $ 197.6 The transfers into and out of Level 3 were due to changes in the availability of market observable inputs. Note 11 - Fair Value Measurements (Continued) Information by security type pertaining to the changes in the fair value of the Company’s investments classified as Level 3 for the nine months ended September 30, 2022 is presented below. Fixed Maturities Equity Securities (Dollars in Millions) Corporate Redeemable Other Mortgage- Preferred Total Balance at Beginning of Year $ 236.8 $ 6.1 $ 7.0 $ 1.5 $ 251.4 Total (Losses) Gains: Included in Condensed Consolidated Statements of Loss (12.2) — — — (12.2) Included in Other Comprehensive Loss (12.2) (1.3) (1.8) 0.2 (15.1) Purchases 115.1 2.0 — 2.7 119.8 Settlements — — — — — Sales (126.0) — — (1.9) (127.9) Transfers into Level 3 22.9 — — — 22.9 Transfers out of Level 3 (5.7) — — — (5.7) Balance at End of Period $ 218.7 $ 6.8 $ 5.2 $ 2.5 $ 233.2 The transfers into and out of Level 3 were due to changes in the availability of market observable inputs. Information by security type pertaining to the changes in the fair value of the Company’s investments classified as Level 3 for the three months ended September 30, 2022 is presented below. Fixed Maturities Equity Securities (Dollars in Millions) Corporate Redeemable Other Mortgage- Preferred Total Balance at Beginning of Period $ 177.1 $ 6.9 $ 5.6 $ 1.7 $ 191.3 Total (Losses) Gains: Included in Condensed Consolidated Statements of Loss (6.3) — — — (6.3) Included in Other Comprehensive Loss (2.8) (0.1) (0.4) — (3.3) Purchases 93.5 — — 2.7 96.2 Settlements — — — — — Sales (60.4) — — (1.9) (62.3) Transfers into Level 3 17.6 — — — 17.6 Transfers out of Level 3 — — — — — Balance at End of Period $ 218.7 $ 6.8 $ 5.2 $ 2.5 $ 233.2 Note 11 - Fair Value Measurements (Continued) The table below shows investments reported at fair value using net asset value (“NAV”) and their unfunded commitments by asset class as of September 30, 2023 and December 31, 2022. September 30, 2023 December 31, 2022 Asset Class Fair Value Using NAV Unfunded Commitments Fair Value Using NAV Unfunded Commitments Reported as Equity Method Limited Liability Investments at Cost Plus Cumulative Undistributed Earnings: Mezzanine Debt $ 123.8 $ 45.8 $ 114.3 $ 51.6 Senior Debt 21.7 41.3 21.6 42.0 Distressed Debt 8.0 — 9.4 — Secondary Transactions 8.2 1.7 9.3 1.7 Hedge Fund 0.1 — 0.5 — Leveraged Buyout 9.9 0.6 8.9 0.6 Growth Equity 1.2 — 1.2 — Real Estate 41.6 — 43.3 — Other 9.6 — 8.5 — Total Equity Method Limited Liability Investments 224.1 89.4 217.0 95.9 Alternative Energy Partnership Investments 17.2 — 16.3 — Reported as Other Equity Interests at Fair Value: Mezzanine Debt 121.9 62.8 106.0 56.0 Senior Debt 25.1 10.5 21.9 6.0 Distressed Debt 12.8 13.0 12.5 13.0 Secondary Transactions 2.9 3.1 3.5 4.2 Hedge Funds 3.0 — 18.1 — Leveraged Buyout 21.6 7.0 21.6 9.0 Growth Equity 6.1 6.7 5.4 7.9 Real Estate 0.1 0.2 — — Other — — 0.1 0.2 Total Reported as Other Equity Interests at Fair Value 193.5 103.3 189.1 96.3 Reported as Equity Securities at Modified Cost: Other 5.3 — 8.3 — Total Reported as Equity Securities at Modified Cost 5.3 — 8.3 — Total Investments in Limited Liability Companies and Limited Partnerships $ 440.1 $ 192.7 $ 430.7 $ 192.2 At September 30, 2023, the Company had unfunded commitments to invest an additional $192.7 million in certain limited liability investment companies and limited partnerships that will be included in Other Equity Interests and Equity Method Limited Liability Investments if funded. Note 11 - Fair Value Measurements (Continued) The fund investments included above (excluding Hedge Funds) are not redeemable, because distributions from the funds will be received when underlying investments of the funds are liquidated. The funds are generally expected to have approximately 10 year lives at their inception, but these lives may be extended at the fund manager’s discretion, typically in one or two-year increments. The hedge fund investments included above, which are carried at fair value, are generally redeemable subject to the redemption notices period. The majority of the hedge fund investments are redeemable monthly or quarterly. The following table includes information related to the Company’s investments in certain private equity funds or hedge funds that calculate a net asset value per share: Asset Class Investment Category Includes Mezzanine Debt Funds with investments in junior or subordinated debt and potentially minority equity securities issued by private companies. Senior Debt Funds with investments in senior or first lien debt and potentially minority equity securities typically issued by private companies. Distressed Debt Funds with debt or minority equity investments that are made opportunistically in companies that are in or near default or under financial strain with potential to have an active role in restructuring company. Secondary Transactions Funds that focus on purchasing third party fund interests from investors seeking liquidity within their own portfolio. Hedge Fund Funds that focus primarily on investing in public securities with strategy of generating uncorrelated returns to the public markets. Leveraged Buyout Funds with control equity investments in more mature, positive cash flowing, private companies that are typically purchased with the use of financial leverage. Growth Equity Funds that invest in early or venture stage companies with high growth potential with view towards generating realizations through sale or initial public offering (“IPO”) of company. Real Estate Funds with investments in multi-family housing properties. Other Consists of direct investments of preferred equity or minority common equity investments into private companies structured as limited partnerships or limited liability companies. Presented below are the carrying values and fair value estimates of financial instruments not carried at fair value. September 30, 2023 December 31, 2022 (Dollars in Millions) Carrying Value Fair Value Carrying Value Fair Value Financial Assets: Loans to Policyholders $ 281.8 $ 281.8 $ 283.4 $ 283.4 Short-term Investments 418.5 418.5 278.4 278.4 Mortgage Loans 98.5 98.5 91.1 91.1 Company-Owned Life Insurance 506.9 506.9 586.5 586.5 Equity Securities at Modified Cost 33.1 33.1 38.4 38.4 Financial Liabilities: Long-term Debt $ 1,388.6 $ 1,158.0 $ 1,386.9 $ 1,195.1 Policyholder Obligations 557.4 557.4 601.0 601.0 Note 11 - Fair Value Measurements (Continued) Loans to policyholders are carried at unpaid principal balance which approximates fair value and are categorized as Level 3 within the fair value hierarchy. The nature of policy loans is to have a negligible default risk as the loans are fully collateralized by the value of the policy. Policy loans do not have a stated maturity and the balances and accrued interest are repaid either by the policyholder or with proceeds from the policy. Due to the collateralized nature of policy loans and unpredictable timing of payments, the Company believes the carrying value of policy loans approximates fair value. The fair value measurement of Short-term Investments is estimated using inputs that are considered either Level 1 or Level 2 measurements. The Mortgage Loans fair value measurement is considered equal to amortized cost given the short-term nature of the investments. The fair value measurement of Equity Securities at Modified Cost is estimated using inputs that are considered Level 3 measurements. The cash surrender value of Company-Owned Life Insurance approximates fair value and is considered to be a Level 2 investment. The fair value of Long-term Debt is estimated using quoted prices for similar liabilities in markets that are not active. The inputs used in the valuation are considered Level 2 measurements. Policyholder Obligations presented in the preceding table consist of advances from the Federal Home Loan Bank (“FHLB”) of Chicago, and the inputs used in the valuation are considered Level 2 measurements.

Variable Interest Entities

Variable Interest Entities	9 Months Ended
	Sep. 30, 2023
Equity Method Investments and Joint Ventures [Abstract]
Variable Interest Entity Disclosure	Variable Interest Entities A VIE is a legal entity that does not have sufficient equity at risk to finance its activities without additional subordinated financial support or is structured such that equity investors lack the ability to make significant decisions relating to the entity's operations through voting rights or do not substantively participate in the gains and losses of the entity. The Company consolidates VIEs in which the Company is deemed the primary beneficiary. The primary beneficiary is the entity that has both (1) the power to direct the activities of the VIE that most significantly affect that entity's economic performance and (2) the obligation to absorb losses or the right to receive benefits that could be potentially significant to the VIE. Reciprocal Exchange The Company has formed a management company that acts as attorney-in-fact (“AIF”) for Kemper Reciprocal (the “Reciprocal Exchange” or “Exchange”), an Illinois-domiciled reciprocal insurance exchange. The Exchange principally writes specialty personal automobile policies sold to subscribers of the Exchange. The establishment of Kemper Reciprocal was completed in the third quarter of 2023. The Company consolidates the Exchange since (1) the AIF manages the business operations of the Exchange and therefore has the power to direct the activities that most significantly impact the economic performance of the Exchange and (2) the Company has provided capital to the Exchange and would absorb any expected losses that could potentially be significant to the Exchange. The Exchange’s anticipated economic performance is the product of its underwriting and investment results. The AIF receives a management fee for the services provided to the Reciprocal Exchange. The management fee revenues are based upon all premiums written or assumed by the Exchange. The AIF determines the management fee rate to be paid by the Exchange. This rate cannot exceed 30% of the Exchange’s gross written and assumed premiums. The assets of the Reciprocal Exchange can be used only to settle the obligations of the Reciprocal Exchange for which creditors and other beneficial owners have no recourse to the Company. The Company has no obligation related to any underwriting and/or investment losses experienced by the Exchange. As of September 30, 2023, the Company contributed $4.0 million of surplus to the Reciprocal Exchange. The effects of the transactions between the Company and the Reciprocal Exchange are eliminated in consolidation to derive consolidated Net Loss. However, the management fee income earned by the AIF is reported in Net Loss attributable to Kemper Corporation and is included in the basic and diluted earnings per share. Noncontrolling interest is the portion of equity (net assets) not attributable, directly or indirectly, to a parent. Since the Company has no ownership interest in the Exchange, the difference between the value of the Exchange’s assets and liabilities represents noncontrolling interest and any income or loss generated by the net assets of the Exchange is presented as income or loss attributable to noncontrolling interest. Alternative Energy Partnership The Company invests in an Alternative Energy Partnership formed to provide sustainable energy projects that are designed to generate a return primarily through the realization of federal tax credits. This entity was formed to invest in newly installed residential solar leases and power purchase agreements. As a result of this investment, the Company has the right to certain investment tax credits and tax depreciation benefits, and to a lesser extent, cash flows generated from the installed solar systems leased to individual consumers. Note 12 - Variable Interest Entities (Continued) The Company’s interest in the Alternative Energy Partnership Investment is considered an investment in a VIE. The Company has determined that it is not the primary beneficiary as it does not have the power to direct the activities that most significantly impact the economic performance of the entity and therefore is not required to consolidate the VIE. The project sponsor governs the entity and the Company only has consent rights that have been deemed protective in nature and does not participate in key economic decisions of the entity. The investment is accounted for using the equity method of accounting and included in Alternative Energy Partnership Investments in the Condensed Consolidated Balance Sheets. The Company uses the HLBV equity method to account for earnings and losses. This method provides an earnings allocation that appropriately reflects the substantive economics of the investment. Earnings and losses on the investment are reported in Change in Value of Alternative Energy Partnership Investments and investment tax credits are recognized in Income Tax Benefit on the Consolidated Statements of Loss. The following table presents information regarding activity in the Company’s Alternative Energy Partnership Investments for the nine and three months ended September 30, 2023 and 2022. Nine Months Ended Three Months Ended (Dollars in millions) Sep 30, 2023 Sep 30, 2022 Sep 30, 2023 Sep 30, 2022 Fundings $ — $ — $ — $ — Cash Distribution from Investment 1.5 1.5 0.5 0.6 Income (Loss) on Investments in Alternative Energy Partnership 2.3 (21.2) 0.8 0.4 Income Tax (Recaptures) Credits Recognized (0.1) 3.9 — — Tax (Expense) Benefit Recognized from Alternative Energy Partnership (0.5) 4.1 (0.2) (0.1) The following table represents the carrying value of the associated assets and liabilities and the associated maximum loss exposure of the Alternative Energy Partnership Investments as of September 30, 2023 and December 31, 2022. (Dollars in millions) Sep 30, 2023 Dec 31, 2022 Cash $ 2.8 $ 3.0 Equipment, Net of Depreciation 256.6 261.7 Other Assets 6.9 5.1 Total Unconsolidated Assets 266.4 269.7 Maximum Loss Exposure 17.2 16.3 The Company’s maximum loss exposure in the event that all of the assets in the Alternative Energy Partnership are deemed worthless is $17.2 million and $16.3 million, which is the carrying value of the investment at September 30, 2023 and December 31, 2022, respectively.

Other Comprehensive Income (Los

Other Comprehensive Income (Loss) and Accumulated Other Comprehensive Income	9 Months Ended
	Sep. 30, 2023
Statement of Comprehensive Income [Abstract]
Other Comprehensive Income (Loss) and Accumulated Other Comprehensive Income	and Accumulated Other Comprehensive Loss The tables below display the changes in Accumulated Other Comprehensive Loss by component for the nine months ended September 30, 2023 and 2022. (Dollars in Millions) Net Unrealized Losses on Other Investments Net Unrealized Losses on Investments with an Allowance for Credit Losses Net Unrecognized Postretirement Benefit Costs Gain on Cash Flow Hedge Change in Discount Rate on Future Life Policyholder Benefits Total Balance as of January 1, 2023 $ (719.4) $ (2.2) $ (37.2) $ 2.8 $ 241.1 (514.9) Other Comprehensive (Loss) Income Before Reclassifications (183.3) 0.5 (5.4) — 171.9 (16.3) Amounts Reclassified from Accumulated Other Comprehensive Loss Net of Tax (Expense) Benefit of $(1.7), $0.5, $(14.1), $0.0, $0.0 and $(15.3) 6.5 (1.7) 53.1 (0.1) — 57.8 Other Comprehensive (Loss) Income Net of Tax Benefit (Expense) of $47.1, $0.4, $(12.6), $0.0, $(45.7), and $(10.8) (176.8) (1.2) 47.7 (0.1) 171.9 41.5 Balance as of September 30, 2023 $ (896.2) $ (3.4) $ 10.5 $ 2.7 $ 413.0 $ (473.4) (Dollars in Millions) Net Unrealized Gains (Losses) on Other Investments Net Unrealized Losses on Investments with an Allowance for Credit Losses Net Unrecognized Postretirement Benefit Costs (Loss) Gain on Cash Flow Hedge Change in Discount Rate on Future Life Policyholder Benefits Total Balance as of January 1, 2022 $ 505.8 $ (3.7) $ (52.1) $ (1.9) $ (849.7) $ (401.6) Other Comprehensive (Loss) Income Before Reclassifications (1,281.0) (1.0) — 4.7 1,122.5 (154.8) Amounts Reclassified from Accumulated Other Comprehensive Loss Net of Tax Benefit of $4.5, $0.0, $0.0, $0.0, $0.0 and $4.5 (17.2) — (0.2) — — (17.4) Other Comprehensive (Loss) Income Net of Tax Benefit (Expense) of $345.0, $0.3, $0.1, $(1.2), $(298.4), and $45.8 (1,298.2) (1.0) (0.2) 4.7 1,122.5 (172.2) Balance as of September 30, 2022 $ (792.4) $ (4.7) $ (52.3) $ 2.8 $ 272.8 $ (573.8) Note 13 - Other Comprehensive Income (Loss) and Accumulated Other Comprehensive Loss (Continued) The tables below display the changes in Accumulated Other Comprehensive Loss by component for the three months ended September 30, 2023 and 2022. (Dollars in Millions) Net Unrealized Losses on Other Investments Net Unrealized Losses on Investments with an Allowance for Credit Losses Net Unrecognized Postretirement Benefit Costs Gain on Cash Flow Hedge Change in Discount Rate on Future Life Policyholder Benefits Total Balance as of June 30, 2023 $ (637.6) $ (2.3) $ (38.0) $ 2.7 $ 194.4 $ (480.8) Other Comprehensive (Loss) Income Before Reclassifications (258.7) (0.9) (5.4) — 218.6 (46.4) Amounts Reclassified from Accumulated Other Comprehensive Loss Net of Tax Benefit (Expense) of $0.1, $0.1, $(14.4), $0.0, $0.0 and $(14.2) 0.1 (0.2) 53.9 — — 53.8 Other Comprehensive (Loss) Income Net of Tax Benefit (Expense) of $67.5, $0.8, $(12.6), $0.0, $(58.2), and $(2.5) (258.6) (1.1) 48.5 — 218.6 7.4 Balance as of September 30, 2023 $ (896.2) $ (3.4) $ 10.5 $ 2.7 $ 413.0 $ (473.4) (Dollars in Millions) Net Unrealized Losses on Other Investments Net Unrealized Losses on Investments with an Allowance for Credit Losses Net Unrecognized Postretirement Benefit Costs Gain on Cash Flow Hedge Change in Discount Rate on Future Life Policyholder Benefits Total Balance as of June 30, 2022 $ (467.3) $ (4.1) $ (52.2) $ 2.8 $ 11.4 $ (509.4) Other Comprehensive (Loss) Income Before Reclassifications (309.1) (0.6) — — 261.4 (48.3) Amounts Reclassified from Accumulated Other Comprehensive Loss Net of Tax Benefit of $4.3, $0.0,$0.0, $0.0, $0.0, and $4.3 (16.0) — (0.1) — — (16.1) Other Comprehensive (Loss) Income Net of Tax Benefit (Expense) of $86.4, $0.2, $0.1, $0.0 $(69.5) and $17.2 (325.1) (0.6) (0.1) — 261.4 (64.4) Balance as of September 30, 2022 $ (792.4) $ (4.7) $ (52.3) $ 2.8 $ 272.8 $ (573.8) Amounts reclassified from Accumulated Other Comprehensive Loss shown above are reported in Net Loss as follows: Components of AOCI Consolidated Statements of Loss Line Item Affected by Reclassifications Net Unrealized Gains (Losses) on Other Investments and Net Unrealized Gains (Losses) on Investments with an Allowance for Credit Losses Net Realized Investment (Losses) Gains and Impairment Gains (Losses) Net Unrecognized Postretirement Benefit Costs Policyholders’ Benefits and Incurred Losses and Loss Adjustment Expenses, Insurance Expenses, and Interest and Other Expenses (Loss) Gain on Cash Flow Hedges Interest and Other Expenses Change in Discount Rate on Future Life Policyholder Benefits Not Applicable

Stockholders_ Equity

Stockholders’ Equity	9 Months Ended
	Sep. 30, 2023
Stockholders' Equity Note [Abstract]
Stockholders' Equity	Shareholders’ Equity Common Stock Repurchases On May 6, 2020, Kemper’s Board of Directors authorized the repurchase of up to an additional $200.0 million of Kemper’s common stock, in addition to $133.3 million remaining under the August 6, 2014 authorization, bringing the remaining share repurchase authorization to approximately $333.3 million. As of September 30, 2023, the remaining share repurchase authorization was $171.6 million under the repurchase program. During the nine and three months ended September 30, 2023 and 2022, Kemper did not repurchase any shares of its common stock. Employee Stock Purchase Plan During the nine months ended September 30, 2023 and 2022, the Company issued 68,000 and 79,000 shares under the Kemper Employee Stock Purchase Plan (“ESPP”), respectively, at an average discounted price of $40.61 and $40.54 per share. Compensation costs charged against income were $0.5 million and $0.6 million for the nine months ended September 30, 2023 and 2022, respectively. During the three months ended September 30, 2023 and 2022, the Company issued 24,000 and 31,000 shares under the ESPP at a discounted price of $35.73 and $35.07 per share, respectively. Compensation costs charged against income were $0.2 million and $0.2 million for the three months ended September 30, 2023 and 2022, respectively.

Pension Benefits and Postretire

Pension Benefits and Postretirement Benefits Other Than Pensions	9 Months Ended
	Sep. 30, 2023
Retirement Benefits [Abstract]
Pension Benefits and Postretirement Benefits Other Than Pensions	Pension Benefits and Postretirement Benefits Other Than Pensions The Company sponsored a qualified defined benefit pension plan (the “Pension Plan”) that covered approximately 3,100 participants and beneficiaries. Effective January 1, 2006, the Pension Plan was closed to new hires and, effective June 30, 2016, benefit accruals were frozen for substantially all of the participants under the Pension Plan. The Pension Plan was generally non-contributory, but participation required some employees to contribute 3% of pay, as defined, per year. Benefits for participants who were required to contribute to the Pension Plan were based on compensation during plan participation and the number of years of participation. Benefits for the vast majority of participants who are not required to contribute to the Pension Plan are based on years of service and final average pay, as defined. The Company funded the Pension Plan in accordance with the requirements of the Employee Retirement Income Security Act of 1974 (“ERISA”). In the third quarter of 2023, the Company's Pension Plan made lump-sum payments to certain inactive vested plan participants that are not currently receiving benefit payments and elected to receive lump-sum payments and purchased annuities on behalf of remaining plan participants. For plan participants who elected lump-sum payments during the election window, payments of $90.0 million were distributed. Group annuity contracts were purchased from Banner Life Insurance Company for $205.7 million for the remaining plan participants for whom Banner irrevocably assumed the pension obligations. These transactions resulted in a full settlement of the Pension Plan and a $70.2 million noncash settlement charge ($55.5 million after-tax) for the unamortized net unrecognized postretirement benefit costs related to the settled obligations recorded in Interest and Other Expenses on the Condensed Consolidated Statements of Loss. The Pension Plan continues to have approximately $16.0 million of net assets remaining in the trust after the termination and was included within Other Assets in the accompanying consolidated balance sheet as of September 30, 2023. Note 15 - Pension Benefits and Postretirement Benefits Other Than Pensions (Continued) The components of Pension Expense for the Pension Plan for the nine and three months ended September 30, 2023 and 2022 were: Nine Months Ended Three Months Ended (Dollars in Millions) Sep 30, Sep 30, Sep 30, Sep 30, Interest Cost on Projected Benefit Obligation $ 8.4 $ 6.5 $ 1.5 $ 2.2 Expected Return on Plan Assets (7.9) (5.6) (1.4) (1.9) Amortization of Prior Service Cost 0.4 0.5 0.1 0.2 Amortization of Net Actuarial Loss — 1.3 — 0.4 Pension Settlement Expense 70.2 — 70.2 — Total Pension Expense $ 71.1 $ 2.7 $ 70.4 $ 0.9 The Company sponsors two other than pension postretirement benefit (“OPEB”) plans (together the “OPEB Plans”) that together provide medical, dental and/or life insurance benefits to approximately 300 retired and 500 active employees. The components of OPEB Benefit for the OPEB Plans for the nine and three months ended September 30, 2023 and 2022 were: Nine Months Ended Three Months Ended (Dollars in Millions) Sep 30, Sep 30, Sep 30, Sep 30, Service Cost $ 0.1 $ 0.1 $ — $ — Interest Cost on Accumulated Postretirement Benefit Obligation 0.3 0.1 0.1 — Amortization of Prior Service Credit (1.0) (1.0) (0.3) (0.3) Amortization of Net Gain (1.3) (1.3) (0.4) (0.5) Total OPEB Benefit $ (1.9) $ (2.1) $ (0.6) $ (0.8)

Policyholder Contract Liabiliti

Policyholder Contract Liabilities	9 Months Ended
	Sep. 30, 2023
Insurance [Abstract]
Policyholder Contract Liabilities	Policyholder Obligations Policyholder Obligations at September 30, 2023 and December 31, 2022 were as follows: (Dollars in Millions) Sep 30, Dec 31, FHLB Funding Agreements $ 557.4 $ 601.0 Universal Life-type Policyholder Account Balances 98.9 100.3 Total $ 656.3 $ 701.3 FHLB Funding Agreements Kemper’s subsidiary, United Insurance Company of America (“United Insurance”) has entered into funding agreements with the FHLB of Chicago in exchange for cash, which it uses for spread lending purposes. During the nine months ended September 30, 2023, United Insurance received advances of $122.5 million from the FHLB of Chicago and made repayments of $166.1 million under the spread lending program. When a funding agreement is issued, United Insurance is then required to post collateral in the form of eligible securities including mortgage-backed, government, and agency debt instruments for each of the advances that are entered. The fair value of the collateral pledged must be maintained at certain specified levels above the borrowed amount, which can vary depending on the assets pledged. If the fair value of the collateral declines below these specified levels of the amount borrowed, United Insurance would be required to pledge additional collateral or repay outstanding borrowings. Upon any event of default by Note 16 - Policyholder Obligations (Continued) United Insurance, the FHLB’s recovery on the collateral is limited to the amount of United Insurance’s liability under the funding agreements to the FHLB of Chicago. United Insurance’s liability under the funding agreements with the FHLB of Chicago, the amount of collateral pledged under such agreements and FHLB of Chicago common stock owned by United Insurance at September 30, 2023 and December 31, 2022 is presented below. (Dollars in Millions) Sep 30, Dec 31, Liability under Funding Agreements $ 557.4 $ 601.0 Fair Value of Collateral Pledged 619.1 744.6 FHLB of Chicago Common Stock Owned at Cost 16.6 17.5 Universal Life-type Policyholder Account Balances The Company’s weighted-average crediting rate for Universal Life-type Policyholder Account Balances was 5.1% as of September 30, 2023 and 2022. Guaranteed minimum benefit amounts in excess of the current account balances for these contracts were $298.2 million and $311.4 million

Debt

Debt	9 Months Ended
	Sep. 30, 2023
Debt Disclosure [Abstract]
Debt	Debt Amended and Extended Credit Agreement and Term Loan Facility On March 15, 2022, the Company entered into an amended and extended credit agreement. The amended and extended credit agreement increased the borrowing capacity of the existing unsecured credit agreement to $600.0 million and extended the maturity date to March 15, 2027. Furthermore, the amended and extended credit agreement provides for an accordion feature whereby the Company can increase the revolving credit borrowing capacity by an additional $200.0 million for a total maximum capacity of $800.0 million. Financial covenants within the agreement limit the Company from accessing the maximum capacity. The amount available as of September 30, 2023 was $376.0 million. There were no outstanding borrowings under the credit agreement at either September 30, 2023 or December 31, 2022. Long-term Debt Total amortized cost of Long-term Debt outstanding at September 30, 2023 and December 31, 2022 was: (Dollars in Millions) Sep 30, Dec 31, Senior Notes: 4.350% Senior Notes due February 15, 2025 $ 449.6 $ 449.3 2.400% Senior Notes due September 30, 2030 396.9 396.6 3.800% Senior Notes due February 23, 2032 395.8 395.5 5.875% Fixed-Rate Reset Junior Subordinated Debentures Due 2062 146.3 145.5 Total Long-term Debt Outstanding $ 1,388.6 $ 1,386.9 4.350% Senior Notes Due 2025 Kemper has $450.0 million aggregate principal of 4.350% senior notes due February 15, 2025 (the “2025 Senior Notes”). Kemper initially issued $250.0 million of the notes in February of 2015 and issued an additional $200.0 million of the notes in June of 2017. The additional notes are fungible with the initial notes issued in 2015, and together are treated as part of a single series for all purposes under the indenture governing the 2025 Senior Notes. The 2025 Senior Notes are unsecured and may be redeemed in whole at any time or in part from time to time at Kemper’s option at specified redemption prices. Note 17 - Debt (Continued) 2.400% Senior Notes Due 2030 Kemper has $400.0 million aggregate principal of 2.400% senior notes due September 30, 2030 (the “2030 Senior Notes”). The net issuance proceeds were $395.8 million, net of discount and transaction costs for an effective yield of 2.52%. The 2030 Senior Notes are unsecured and may be redeemed in whole at any time or in part from time to time, at Kemper’s option, at specified redemption prices. 3.800% Senior Notes Due 2032 On February 15, 2022, Kemper offered and sold $400.0 million aggregate principal of 3.800% senior notes due February 23, 2032 (the “2032 Senior Notes”). The net proceeds of issuance were $395.1 million, net of discount and transaction costs, for an effective yield of 3.950%. The 2032 Senior Notes are unsecured and may be redeemed in whole at any time or in part from time to time, at Kemper’s option, at specified redemption prices. In anticipation of the issuance of the 2032 Senior Notes and for risk management purposes, the Company entered into a derivative transaction to hedge the risk of changes in the debt cash flows attributable to changes in the benchmark U.S. Treasury interest rate during the period leading up to the debt issuance (“Treasury Lock”). The effective portion of the gain on the derivative instrument upon discontinuance was $5.9 million before taxes, and is reported as a component of Accumulated Other Comprehensive Income (Loss). Beginning with the issuance of the 2032 Senior Notes described in the preceding paragraph, such gain is being amortized into earnings and reported in Interest and Other Expenses in the same periods that the hedged items affect earnings. Amortization, reported in Interest and Other Expenses, was $0.4 million for the nine months ended September 30, 2023. The Company expects to reclassify $0.5 million of net gain on derivative instruments from AOCI to earnings for the twelve months ended September 30, 2024 as interest expense on the debt is recognized. 5.875% Fixed-Rate Reset Junior Subordinated Debentures Due 2062 On March 10, 2022, Kemper issued $150.0 million aggregate principal amount of 5.875% Fixed-Rate Reset Junior Subordinated Debentures due March 15, 2062 (the “2062 Junior Debentures”). The net proceeds from issuance were $144.7 million, net of discount and transaction costs. The 2062 Junior Debentures will bear interest from and including the date of original issue to, but excluding, March 15, 2027 (the “First Reset Date”) at the fixed rate of 5.875% per annum. The interest rate on the First Reset Date, and subsequent Reset Dates, will be equal to the Five-Year Treasury Rate as of the most recent Reset Date plus 4.140% to be reset on each Reset Date. Interest is due quarterly in arrears beginning on June 15, 2022. The Company has the option to defer interest payments for one or more optional deferral periods of up to five consecutive years, provided that no optional deferral period shall extend beyond March 15, 2062, or any earlier accelerated maturity date arising from an event of default or any earlier redemption of the 2062 Junior Debentures. The 2062 Junior Debentures are unsecured and may be redeemed in whole or in part on the First Reset Date or any time thereafter, at a redemption price equal to the principal amount of the debentures being redeemed plus any accrued and unpaid interest. Short-term Debt Kemper’s subsidiaries, United Insurance, Trinity Universal Insurance Company (“Trinity”) and American Access Casualty Company (“AAC”), are members of the FHLBs of Chicago, Dallas and Chicago, respectively. Alliance United Insurance Company (“Alliance”) was a member of the FHLB of San Francisco until it surrendered all California licenses on January 30, 2023, and ceased to exist as an insurance company. As a requirement of membership in the FHLBs, United Insurance, Trinity, and AAC maintain a certain level of investment in FHLB stock. The Company periodically uses short-term FHLB borrowings for cash management and risk management purposes, in addition to long-term FHLB borrowings for the spread lending program. No short-term debt advances from the FHLBs of Chicago or Dallas were outstanding on September 30, 2023 or December 31, 2022. For information on United Insurance’s funding agreement with the FHLB of Chicago in connection with the spread lending program, see Note 16, “Policyholder Obligations,” to the Condensed Consolidated Financial Statements. Interest Expense and Interest Paid Interest Expense, including facility fees, accretion of discount, amortization of premium and amortization of issuance costs, was $42.2 million and $14.1 million for the nine and three months ended September 30, 2023 and, respectively. Interest Note 17 - Debt (Continued) paid, including facility fees, was $47.2 million and $19.9 million for the nine and three months ended September 30, 2023, respectively. Interest Expense, including facility fees, accretion of discount and amortization of issuance costs, was $41.0 million and $14.3 million for the nine and three months ended September 30, 2022, respectively. Interest paid, including facility fees, was $49.4 million and $25.0 million for the nine and three months ended September 30, 2022, respectively.

Leases

Leases	9 Months Ended
	Sep. 30, 2023
Leases [Abstract]
Leases	Leases The Company leases certain office space under non-cancelable operating leases, with initial terms typically ranging from one one The following table presents operating lease right-of-use assets and lease liabilities. (Dollars in Millions) Sep 30, Dec 31, Operating Lease Right-of-Use Assets $ 34.7 $ 45.1 Operating Lease Liabilities 60.6 72.6 Lease expenses are primarily included in Insurance Expenses in the Condensed Consolidated Statements of Loss. Additional information regarding the Company’s lease cost is presented below. Nine Months Ended Three Months Ended (Dollars in Millions) Sep 30, Sep 30, Sep 30, Sep 30, Lease Cost: Operating Lease Cost $ 11.9 $ 17.2 $ 4.0 $ 5.8 Variable Lease Cost 3.2 0.2 1.0 0.1 Short-Term Lease Cost 1 0.5 3.2 (0.3) 1.0 Total Lease Expense $ 15.6 $ 20.6 $ 4.7 $ 6.9 Less: Sub-Lease Income — 0.1 — — Total Lease Cost $ 15.6 $ 20.5 $ 4.7 $ 6.9 1 Leases with an initial term of twelve months or less are not recorded on the Condensed Consolidated Balance Sheets. The Company incurred expenses of $18.0 million and $14.8 million during the nine and three months ended September 30, 2023, respectively, associated with lease abandonments. The Company had no expenses during the nine and three months ended September 30, 2022, respectively, associated with lease abandonments. Other Information on Operating Leases Supplemental cash flow information related to the Company’s operating leases for the nine months ended September 30, 2023 and 2022 is as follows: Nine Months Ended (Dollars in Millions) Sep 30, Sep 30, Operating Cash Flows from Operating Lease (Fixed Payments) $ 19.6 $ 19.1 Operating Cash Flows from Operating Lease (Liability Reduction) 17.8 17.1 Right-of-Use Assets Obtained in Exchange for New Operating Lease Liabilities 6.6 10.1 As of September 30, 2023, the Company does not have any finance leases. Note 18 - Leases (Continued) Significant judgments and assumptions for determining lease asset and liability at September 30, 2023 and 2022 are presented below. Nine Months Ended Sep 30, Sep 30, Weighted-average Remaining Lease Term - Finance Leases N/A 0.3 years Weighted-average Remaining Lease Term - Operating Leases 5.6 years 5.6 years Weighted-average Discount Rate - Finance Leases N/A 0.6 % Weighted-average Discount Rate - Operating Leases 4.0 % 3.4 % Most of the Company’s leases do not provide an implicit rate. Accordingly, the Company uses its incremental borrowing rate based on the information available at the commencement date to determine its lease payments’ present value. Future minimum lease payments under operating leases at September 30, 2023 are presented below. There are no significant future minimum lease payments under finance leases. (Dollars in Millions) Sep 30, 2023 Remainder of 2023 $ 5.7 2024 19.3 2025 14.5 2026 8.5 2027 6.3 2028 and Thereafter 19.1 Total Future Payments $ 73.4 Less Imputed Interest 12.8 Present Value of Minimum Lease Payments $ 60.6
Leases	Leases The Company leases certain office space under non-cancelable operating leases, with initial terms typically ranging from one one The following table presents operating lease right-of-use assets and lease liabilities. (Dollars in Millions) Sep 30, Dec 31, Operating Lease Right-of-Use Assets $ 34.7 $ 45.1 Operating Lease Liabilities 60.6 72.6 Lease expenses are primarily included in Insurance Expenses in the Condensed Consolidated Statements of Loss. Additional information regarding the Company’s lease cost is presented below. Nine Months Ended Three Months Ended (Dollars in Millions) Sep 30, Sep 30, Sep 30, Sep 30, Lease Cost: Operating Lease Cost $ 11.9 $ 17.2 $ 4.0 $ 5.8 Variable Lease Cost 3.2 0.2 1.0 0.1 Short-Term Lease Cost 1 0.5 3.2 (0.3) 1.0 Total Lease Expense $ 15.6 $ 20.6 $ 4.7 $ 6.9 Less: Sub-Lease Income — 0.1 — — Total Lease Cost $ 15.6 $ 20.5 $ 4.7 $ 6.9 1 Leases with an initial term of twelve months or less are not recorded on the Condensed Consolidated Balance Sheets. The Company incurred expenses of $18.0 million and $14.8 million during the nine and three months ended September 30, 2023, respectively, associated with lease abandonments. The Company had no expenses during the nine and three months ended September 30, 2022, respectively, associated with lease abandonments. Other Information on Operating Leases Supplemental cash flow information related to the Company’s operating leases for the nine months ended September 30, 2023 and 2022 is as follows: Nine Months Ended (Dollars in Millions) Sep 30, Sep 30, Operating Cash Flows from Operating Lease (Fixed Payments) $ 19.6 $ 19.1 Operating Cash Flows from Operating Lease (Liability Reduction) 17.8 17.1 Right-of-Use Assets Obtained in Exchange for New Operating Lease Liabilities 6.6 10.1 As of September 30, 2023, the Company does not have any finance leases. Note 18 - Leases (Continued) Significant judgments and assumptions for determining lease asset and liability at September 30, 2023 and 2022 are presented below. Nine Months Ended Sep 30, Sep 30, Weighted-average Remaining Lease Term - Finance Leases N/A 0.3 years Weighted-average Remaining Lease Term - Operating Leases 5.6 years 5.6 years Weighted-average Discount Rate - Finance Leases N/A 0.6 % Weighted-average Discount Rate - Operating Leases 4.0 % 3.4 % Most of the Company’s leases do not provide an implicit rate. Accordingly, the Company uses its incremental borrowing rate based on the information available at the commencement date to determine its lease payments’ present value. Future minimum lease payments under operating leases at September 30, 2023 are presented below. There are no significant future minimum lease payments under finance leases. (Dollars in Millions) Sep 30, 2023 Remainder of 2023 $ 5.7 2024 19.3 2025 14.5 2026 8.5 2027 6.3 2028 and Thereafter 19.1 Total Future Payments $ 73.4 Less Imputed Interest 12.8 Present Value of Minimum Lease Payments $ 60.6

Income Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2023
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The statute of limitations related to Kemper and its eligible subsidiaries’ consolidated Federal income tax returns is closed for all tax years up to and including 2011 and 2018. As a result of the Company filing amended federal income tax returns, tax years 2012 and 2013 are under limited examination for carry-back adjustments associated with the amended returns. The statute of limitations related to tax years 2014, 2015, 2016 and 2017 has been extended to June 30, 2024. Tax years 2019, 2020 and 2021 are subject to a statute of three years from the extended due dates of October 15, 2020, 2021, and 2022, respectively. The expiration of the statute of limitations related to the various state income tax returns that Kemper and its subsidiaries file varies by state. There were no Unrecognized Tax Benefits at September 30, 2023, or December 31, 2022. The Company recognizes interest and penalties, if any, related to unrecognized tax benefits in Income Tax Benefit. For the nine months ended September 30, 2023 and 2022, federal income tax refunds received, net of income taxes paid, were $113.6 million and $0.4 million, respectively.

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2023
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and ContingenciesIn the ordinary course of its businesses, the Company is involved in legal proceedings including lawsuits, arbitration, regulatory examinations, audits and inquiries. Based on currently available information, the Company does not believe that it is reasonably possible that any of its pending legal proceedings will have a material effect on the Company’s Condensed Consolidated Financial Statements and Notes to the Condensed Consolidated Financial Statements.

Basis of Presentation and Acc_2

Basis of Presentation and Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Adoption of New Accounting Guidance and Guidance Not Yet Adopted	Adoption of New Accounting Guidance The Company has adopted all recently issued accounting pronouncements with effective dates prior to September 30, 2023. Other than discussed below, there were no adoptions of accounting pronouncements during the nine months ended September 30, 2023 that had a material impact on the Company’s Condensed Consolidated Financial Statements. Guidance Adopted in 2023

Basis of Presentation and Acc_3

Basis of Presentation and Accounting Policies (Tables)	9 Months Ended
	Sep. 30, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Accounting Standards Update and Change in Accounting Principle	The table below presents the transition adjustment for the adoption of ASU 2018-12: Pre-Adoption Balance 12/31/2020 Adjustments to AOCI Adjustments to Retained Earnings Post- Adoption Balance 1/1/2021 Retained Earnings $ 2,071.2 — (25.1) $ 2,046.1 AOCI $ 680.5 (1,030.3) — $ (349.8) Note 1 - Basis of Presentation and Accounting Policies (Continued) For the liability for future policyholder benefits, the net transition adjustment is related to the difference in the historical discount rates used pre-transition and the discount rate at December 31, 2020. At transition, there were no adjustments related to premium deficiencies, as the balance is only applicable to Kemper’s universal life contracts which are stated at account value. The effects of adoption of ASU 2018-12 on the Condensed Consolidated Statement of Loss for the nine months ended September 30, 2022 were as follows: Prior to Adoption Effect of Adoption Post- Adoption Balance Earned Premiums $ 3,999.3 (50.8) $ 3,948.5 Policyholders’ Benefits and Incurred Losses and Loss Adjustment Expenses $ 3,426.1 (66.5) $ 3,359.6 Insurance Expenses $ 913.0 — $ 913.0 Income Tax Benefit $ 68.1 (3.3) $ 64.8 Net Loss attributable to Kemper Corporation $ (245.7) 12.4 $ (233.3) Net Loss Per Unrestricted Share attributable to Kemper Corporation: Basic $ (3.85) $ 0.19 $ (3.66) Diluted $ (3.85) $ 0.19 $ (3.66) The effects of adoption of ASU 2018-12 on the Condensed Consolidated Statement of Loss for the three months ended September 30, 2022 were as follows: Prior to Adoption Effect of Adoption Post- Adoption Balance Earned Premiums $ 1,307.0 (16.1) $ 1,290.9 Policyholders’ Benefits and Incurred Losses and Loss Adjustment Expenses $ 1,102.4 (17.1) $ 1,085.3 Insurance Expenses $ 301.3 (0.8) $ 300.5 Income Tax Benefit $ 13.4 (0.4) $ 13.0 Net Loss attributable to Kemper Corporation $ (76.2) 1.4 $ (74.8) Net Loss Per Unrestricted Share attributable to Kemper Corporation: Basic $ (1.19) $ 0.02 $ (1.17) Diluted $ (1.19) $ 0.02 $ (1.17) The effects of adoption of ASU 2018-12 on the Condensed Consolidated Balance Sheet as of December 31, 2022 were as follows: Prior to Adoption Effect of Adoption Post- Adoption Balance Deferred Policy Acquisition Costs $ 625.6 10.0 $ 635.6 Deferred Income Tax Assets $ 189.4 (60.4) $ 129.0 Total Assets $ 13,364.0 (50.4) $ 13,313.6 Life and Health Insurance Reserves $ 3,554.0 (277.8) $ 3,276.2 Total Liabilities $ 10,920.8 (277.8) $ 10,643.0 Retained Earnings $ 1,380.1 (13.7) $ 1,366.4 Accumulated Other Comprehensive Loss $ (756.0) 241.1 $ (514.9) Total Shareholders’ Equity attributable to Kemper Corporation $ 2,443.2 227.4 $ 2,670.6 Note 1 - Basis of Presentation and Accounting Policies (Continued) The effects of adoption of ASU 2018-12 on the Condensed Consolidated Statement of Comprehensive Loss for the nine months ended September 30, 2022 were as follows: Prior to Adoption Effect of Adoption Post- Adoption Balance Change in Discount Rate on Future Life Policyholder Benefits $ — 1,420.9 $ 1,420.9 Other Comprehensive Loss Before Income Taxes $ (1,638.9) 1,420.9 $ (218.0) Other Comprehensive Income Tax Benefit $ 344.2 (298.4) $ 45.8 Other Comprehensive Loss, Net of Taxes $ (1,294.7) 1,122.5 $ (172.2) Total Comprehensive Loss $ (1,540.4) 1,134.9 $ (405.5) The effects of adoption of ASU 2018-12 on the Condensed Consolidated Statement of Comprehensive Loss for the three months ended September 30, 2022 were as follows: Prior to Adoption Effect of Adoption Post- Adoption Balance Change in Discount Rate on Future Life Policyholder Benefits $ — 330.9 $ 330.9 Other Comprehensive Loss Before Income Taxes $ (412.5) 330.9 $ (81.6) Other Comprehensive Income Tax Benefit $ 86.7 (69.5) $ 17.2 Other Comprehensive Loss, Net of Taxes $ (325.8) 261.4 $ (64.4) Total Comprehensive Loss $ (402.0) 262.8 $ (139.2) The effects of adoption of ASU 2018-12 on the Condensed Consolidated Statement of Cash Flows for the nine months ended September 30, 2022 were as follows: Prior to Adoption Effect of Adoption Post- Adoption Balance Cash Flows from Operating Activities: Net Loss $ (245.7) 12.4 $ (233.3) Change in Deferred Policy Acquisition Costs $ 4.2 — $ 4.2 Change in Insurance Reserves $ (9.3) (15.7) $ (25.0) Change in Income Taxes $ (66.2) 3.3 $ (62.9) Net Cash Used in Operating Activities $ (170.1) — $ (170.1)

Net Income Per Unrestricted S_2

Net Income Per Unrestricted Share (Tables)	9 Months Ended
	Sep. 30, 2023
Earnings Per Share [Abstract]
Schedule of Calculation of Numerator and Denominator in Earnings Per Share	A reconciliation of the numerator and denominator used in the calculation of Basic Net Loss Per Unrestricted Share and Diluted Net Loss Per Unrestricted Share for the nine and three months ended September 30, 2023 and 2022 is presented below. Nine Months Ended Three Months Ended (Dollars in Millions, except per share amounts) Sep 30, Sep 30, Sep 30, Sep 30, Net Loss attributable to Kemper Corporation $ (323.5) $ (233.3) $ (146.3) $ (74.8) Less: Net Loss Attributed to Participating Awards — — — — Net Loss Attributed to Unrestricted Shares (323.5) (233.3) (146.3) (74.8) Dilutive Effect on Income of Equity-based Compensation Equivalent Shares — — — — Diluted Net Loss Attributed to Unrestricted Shares $ (323.5) $ (233.3) $ (146.3) $ (74.8) (Number of Shares in Thousands) Weighted-average Unrestricted Shares Outstanding 64,004.4 63,804.4 64,056.9 63,852.8 Equity-based Compensation Equivalent Shares — — — — Weighted-average Unrestricted Shares and Equivalent Shares Outstanding Assuming Dilution 64,004.4 63,804.4 64,056.9 63,852.8 Net Loss attributable to Kemper Corporation per Unrestricted Share: (Per Unrestricted Share in Whole Dollars) Basic Net Loss Per Unrestricted Share $ (5.05) $ (3.66) $ (2.28) $ (1.17) Diluted Net Loss Per Unrestricted Share $ (5.05) $ (3.66) $ (2.28) $ (1.17)

Business Segments (Tables)

Business Segments (Tables)	9 Months Ended
	Sep. 30, 2023
Segment Reporting [Abstract]
Revenue from External Customers by Products and Services	Earned Premiums by product line, including a reconciliation to Total Earned Premiums, for the nine and three months ended September 30, 2023 and 2022 were: Nine Months Ended Three Months Ended (Dollars in Millions) Sep 30, Sep 30, Sep 30, Sep 30, Specialty Property & Casualty Insurance: Personal Automobile $ 2,278.5 $ 2,666.3 $ 724.0 $ 858.8 Commercial Automobile 488.4 398.5 166.4 140.7 Life Insurance: Life 251.9 253.8 84.9 84.3 Accident and Health 17.5 136.8 5.8 45.9 Property 34.2 38.3 11.4 11.9 Total Segment Earned Premiums $ 3,070.5 $ 3,493.7 $ 992.5 $ 1,141.6 Non-Core Operations 395.1 454.8 125.3 149.3 Total Earned Premiums $ 3,465.6 $ 3,948.5 $ 1,117.8 $ 1,290.9
Reconciliation of Revenue from Segments to Consolidated	Segment Revenues, including a reconciliation to Total Revenues, for the nine and three months ended September 30, 2023 and 2022 were: Nine Months Ended Three Months Ended (Dollars in Millions) Sep 30, Sep 30, Sep 30, Sep 30, Segment Revenues: Specialty Property & Casualty Insurance: Earned Premiums $ 2,766.9 $ 3,064.8 $ 890.4 $ 999.5 Net Investment Income 125.7 102.8 42.7 33.9 Change in Value of Alternative Energy Partnership Investments 1.3 (10.6) 0.5 0.3 Other Income 3.2 5.0 1.6 2.3 Total Specialty Property & Casualty Insurance 2,897.1 3,162.0 935.2 1,036.0 Life Insurance: Earned Premiums 303.6 428.9 102.1 142.1 Net Investment Income 146.3 163.9 49.4 52.6 Change in Value of Alternative Energy Partnership Investments 0.6 (5.6) 0.2 0.1 Other (Loss) Income (0.4) (0.8) (0.1) — Total Life Insurance 450.1 586.4 151.6 194.8 Total Segment Revenues 3,347.2 3,748.4 1,086.8 1,230.8 Income (Loss) from Change in Fair Value of Equity and Convertible Securities 6.9 (79.9) 2.8 (11.2) Net Realized Investment (Losses) Gains (38.3) 0.4 (30.3) (12.1) Net Impairment Gains (Losses) Recognized in Earnings 0.1 (22.1) (1.1) (8.3) Non-Core Operations 431.7 486.0 138.0 161.1 Other 9.4 16.5 3.2 1.2 Total Revenues $ 3,757.0 $ 4,149.3 $ 1,199.4 $ 1,361.5
Reconciliation of Operating Profit (Loss) from Segments to Consolidated	, including a reconciliation to Loss before Income Taxes, for the nine and three months ended September 30, 2023 and 2022 was: Nine Months Ended Three Months Ended (Dollars in Millions) Sep 30, Sep 30, Sep 30, Sep 30, Segment Adjusted Operating (Loss) Income: Specialty Property & Casualty Insurance $ (132.9) $ (150.4) $ (43.2) $ (39.2) Life Insurance 42.4 51.5 17.5 15.6 Total Segment Adjusted Operating Loss (90.5) (98.9) (25.7) (23.6) Corporate and Other Adjusted Operating Loss From: Other (41.5) (32.2) (13.3) (16.6) Corporate and Other Adjusted Operating Loss (41.5) (32.2) (13.3) (16.6) Adjusted Consolidated Operating Loss (132.0) (131.1) (39.0) (40.2) Income (Loss) from Change in Fair Value of Equity and Convertible Securities 6.9 (79.9) 2.8 (11.2) Net Realized Investment (Losses) Gains (38.3) 0.4 (30.3) (12.1) Impairment Gains (Losses) 0.1 (22.1) (1.1) (8.3) Acquisition and Disposition Related Transaction, Integration, Restructuring and Other Costs (101.9) (27.3) (43.3) (12.7) Debt Extinguishment, Pension Settlement and Other Charges (70.2) (3.7) (70.2) — Goodwill Impairment Charge (49.6) — — — Non-Core Operations (25.5) (34.4) (9.6) (3.3) Loss before Income Taxes attributable to Kemper Corporation $ (410.5) $ (298.1) $ (190.7) $ (87.8) Loss before Income Taxes Noncontrolling Interest (0.1) — (0.1) — Loss before Income Taxes $ (410.6) $ (298.1) $ (190.8) $ (87.8)
Reconciliation of Other Significant Reconciling Items from Segments to Consolidated	, including a reconciliation to Net Loss, for the nine and three months ended September 30, 2023 and 2022 was: Nine Months Ended Three Months Ended (Dollars in Millions and Net of Income Taxes) Sep 30, Sep 30, Sep 30, Sep 30, Segment Adjusted Net Operating (Loss) Income: Specialty Property & Casualty Insurance $ (102.4) $ (112.3) $ (33.2) $ (28.7) Life Insurance 36.8 45.8 14.7 14.0 Total Segment Adjusted Net Operating Loss (65.6) (66.5) (18.5) (14.7) Corporate and Other Adjusted Net Operating Loss From: Other (32.2) (26.4) (9.4) (12.3) Total Corporate and Other Adjusted Net Operating Loss (32.2) (26.4) (9.4) (12.3) Adjusted Consolidated Net Operating Loss (97.8) (92.9) (27.9) (27.0) Net Income (Loss) From: Change in Fair Value of Equity and Convertible Securities 5.5 (63.1) 2.3 (8.8) Net Realized Investment (Losses) Gains (30.3) 0.3 (22.9) (9.6) Impairment Gains (Losses) 0.1 (17.5) (0.8) (6.6) Acquisition and Disposition Related Transaction, Integration, Restructuring and Other Costs (80.5) (32.2) (34.2) (20.7) Debt Extinguishment, Pension Settlement and Other Charges (55.5) (2.9) (55.5) — Goodwill Impairment Charge (45.5) — — — Non-Core Operations (19.5) (25.0) (7.3) (2.1) Net Loss attributable to Kemper Corporation $ (323.5) $ (233.3) $ (146.3) $ (74.8) Net Loss Noncontrolling Interest (0.1) — (0.1) — Net Loss $ (323.6) $ (233.3) $ (146.4) $ (74.8)

Property and Casualty Insuran_2

Property and Casualty Insurance Reserves (Tables)	9 Months Ended
	Sep. 30, 2023
Liability for Future Policy Benefits and Unpaid Claims and Claims Adjustment Expense [Abstract]
Liability for Unpaid Claims Adjustment Expense by Expense Type	Property and casualty insurance reserve activity for the nine months ended September 30, 2023 and 2022 was: Nine Months Ended (Dollars in Millions) Sep 30, Sep 30, Property and Casualty Insurance Reserves: Gross of Reinsurance at Beginning of Year $ 2,756.9 $ 2,772.7 Less Reinsurance Recoverables at Beginning of Year 39.6 41.9 Property and Casualty Insurance Reserves, Net of Reinsurance at Beginning of Year 2,717.3 2,730.8 Incurred Losses and Loss Adjustment Expenses (“ LAE”) Related to: Current Year 2,660.5 3,125.0 Prior Years 158.5 (22.5) Total Incurred Losses and LAE 2,819.0 3,102.5 Paid Losses and LAE Related to: Current Year 1,411.8 1,748.9 Prior Years 1,428.9 1,406.6 Total Paid Losses and LAE 2,840.7 3,155.5 Property and Casualty Insurance Reserves, Net of Reinsurance at End of Period 2,695.6 2,677.8 Plus Reinsurance Recoverables at End of Period 28.9 42.5 Property and Casualty Insurance Reserves, Gross of Reinsurance at End of Period $ 2,724.5 $ 2,720.3
Premium Receivable, Allowance for Credit Loss	The following table presents receivables from policyholders, net of the allowance for expected credit losses including a roll forward of changes in the allowance for expected credit losses for the nine months ended September 30, 2023. (Dollars in Millions) Receivables from Policyholders, Net of Allowance for Expected Credit Losses Allowance for Expected Credit Losses Balance at Beginning of Year $ 1,286.6 $ 13.1 Provision for Expected Credit Losses 32.8 Write-offs of Uncollectible Receivables from Policyholders (32.4) Balance at End of Period $ 1,102.6 $ 13.5 The following table presents receivables from policyholders, net of the allowance for expected credit losses including a roll forward of changes in the allowance for expected credit losses for the nine months ended September 30, 2022. (Dollars in Millions) Receivables from Policyholders, Net of Allowance for Expected Credit Losses Allowance for Expected Credit Losses Balance at Beginning of Year $ 1,418.7 $ 13.6 Provision for Expected Credit Losses 36.7 Write-offs of Uncollectible Receivables from Policyholders (37.8) Balance at End of Period $ 1,349.1 $ 12.5

Financial Services, Insurance (

Financial Services, Insurance (Tables)	9 Months Ended
	Sep. 30, 2023
Insurance [Abstract]
Liability for Future Policy Benefit, Activity	The following tables summarize balances and changes in the present value of expected net premiums, present value of expected future policyholder benefits and net liability for future policyholder benefits as of and for the nine and three months ended September 30, 2023 and September 30, 2022: Nine Months Ended Three Months Ended Sep 30, 2023 Sep 30, 2022 Sep 30, 2023 Sep 30, 2022 Present Value of Expected Net Premiums Balance, Beginning of Period $ 688.6 $ 669.0 $ 711.7 $ 646.4 Beginning Balance at Original Discount Rate $ 728.9 $ 599.8 $ 745.1 $ 660.3 Effect of Changes in Cash Flow Assumptions — — — — Effect of Actual Variances from Expected Experience (18.6) 5.2 (6.3) (8.3) Adjusted Beginning of Period Balance 710.3 605.0 738.8 652.0 Issuances 81.6 109.9 19.7 30.5 Interest Accrual 22.2 15.6 7.7 5.3 Net Premiums Collected (71.6) (66.0) (23.7) (23.3) Ending Balance at Original Discount Rate 742.5 664.5 742.5 664.5 Effect of Changes in Discount Rate Assumptions (56.1) (42.7) (56.1) (42.7) Balance, End of Period $ 686.4 $ 621.8 $ 686.4 $ 621.8 Present Value of Expected Future Policyholder Benefits Balance, Beginning of Period $ 3,561.0 $ 4,933.1 $ 3,635.9 $ 3,799.4 Beginning Balance at Original Discount Rate $ 3,906.2 $ 3,788.1 $ 3,915.1 $ 3,827.6 Effect of Changes in Cash Flow Assumptions — — — — Effect of Actual Variances From Expected Experience (21.7) 7.4 (8.5) (7.9) Adjusted Beginning of Period Balance 3,884.5 3,795.5 3,906.6 3,819.7 Issuances 80.8 110.0 18.9 30.5 Interest Accrual 128.2 122.1 43.0 40.7 Benefit Payments (184.4) (197.9) (59.4) (61.2) Ending Balance at Original Discount Rate 3,909.1 3,829.7 3,909.1 3,829.7 Effect of Changes in Discount Rate Assumptions (578.6) (387.8) (578.6) (387.8) Balance, End of Period $ 3,330.5 $ 3,441.9 $ 3,330.5 $ 3,441.9 Net Liability for Future Policyholder Benefits $ 2,644.1 $ 2,820.1 $ 2,644.1 $ 2,820.1 Less: Reinsurance Recoverable — — — — Net Liability for Future Policyholder Benefits, After Reinsurance Recoverable $ 2,644.1 $ 2,820.1 $ 2,644.1 $ 2,820.1
Weighted-Average Liability Duration	The weighted-average liability duration of the liability for future policyholder benefits as calculated under current rates is as follows: Sep 30, 2023 Sep 30, 2022 Weighted-Average Liability Duration of the Liability for Future Policyholder Benefits (Years) 13.8 15.5
Reconciliation of Net Liability for Future Policyholder Benefits	The reconciliation of the net liability for future policyholder benefits to Life and Health Insurance Reserves in the Condensed Consolidated Balance Sheets is as follows: Sep 30, 2023 Sep 30, 2022 Net Liability for Future Policyholder Benefits 2,644.1 2,820.1 Deferred Profit Liability 304.9 249.9 Other 1 149.1 149.8 Total Life and Health Insurance Reserves $ 3,098.1 $ 3,219.8 1 Other primarily consists of Accident and Health and Universal Life reserves
Undiscounted Expected Gross Premiums and Expected Future Benefit Payments	The amounts of expected undiscounted future benefit payments, expected undiscounted future gross premiums and expected discounted future gross premiums, were as follows: Sep 30, 2023 Sep 30, 2022 Expected Future Benefit Payments, undiscounted $ 10,181.5 $ 9,585.4 Expected Future Gross Premiums, undiscounted $ 4,446.4 $ 3,801.1 Expected Future Gross Premiums, discounted $ 2,748.0 $ 2,585.1
Liability for Future Policy Benefits Interest Expense and Premiums	The amount of revenue and interest recognized in the Condensed Consolidated Statements of Loss is as follows: Nine Months Ended Three Months Ended Sep 30, 2023 Sep 30, 2022 Sep 30, 2023 Sep 30, 2022 Gross Premiums or Assessments $ 300.7 $ 297.2 $ 98.4 $ 100.8 Interest Expense $ 106.1 $ 106.5 $ 35.4 $ 35.4
Weighted Average Interest Rate for Future Policyholder Benfits	The weighted-average interest rate is as follows: Sep 30, 2023 Sep 30, 2022 Interest Accretion Rate 4.57 % 4.59 % Current Discount Rate 5.88 % 5.44 %

Deferred Costs, Capitalized, _2

Deferred Costs, Capitalized, Prepaid, and Other Assets (Tables)	9 Months Ended
	Sep. 30, 2023
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Deferred Policy Acquisition Costs	The following table presents the balances and changes in Deferred Policy Acquisition Costs for the Property and Casualty and Life and Health and business for the nine months ended September 30, 2023 and 2022: Sep 30, 2023 Sep 30, 2022 Property and Casualty Life and Health Total Property and Casualty Life and Health Total Balance, Beginning of Year $ 231.1 $ 404.5 $ 635.6 $ 268.7 $ 419.3 $ 688.0 Capitalizations 407.1 42.2 449.3 483.0 47.0 530.0 Amortization Expense (439.1) (14.7) (453.8) (507.2) (21.5) (528.7) Experience Adjustment — (8.9) (8.9) — (5.5) (5.5) Balance 199.1 423.1 622.2 244.5 439.3 683.8 Less: Deferred Policy Acquisition Costs Asset Held-for-Sale — — — — 38.7 38.7 Balance, End of Period $ 199.1 $ 423.1 $ 622.2 $ 244.5 $ 400.6 $ 645.1

Investments (Tables)

Investments (Tables)	9 Months Ended
	Sep. 30, 2023
Debt Securities, Available-for-sale [Line Items]
Investments Classified by Contractual Maturity Date	The amortized cost and fair values of the Company’s Investments in Fixed Maturities at September 30, 2023 by contractual maturity were: (Dollars in Millions) Amortized Cost Fair Value Due in One Year or Less $ 170.8 $ 161.3 Due after One Year to Five Years 915.2 872.0 Due after Five Years to Ten Years 1,089.5 906.1 Due after Ten Years 3,625.5 2,898.1 Mortgage- and Asset-backed Securities Not Due at a Single Maturity Date 1,821.5 1,637.0 Investments in Fixed Maturities $ 7,622.5 $ 6,474.5
Schedule of Unrealized Loss on Investments	An aging of unrealized losses on the Company’s Investments in Fixed Maturities at September 30, 2023 is presented below. Less Than 12 Months 12 Months or Longer Total (Dollars in Millions) Fair Unrealized Fair Unrealized Fair Unrealized Fixed Maturities: U.S. Government and Government Agencies and Authorities $ 93.4 $ (4.1) $ 381.9 $ (108.6) $ 475.3 $ (112.7) States and Political Subdivisions 374.3 (22.0) 873.5 (272.7) 1,247.8 (294.7) Foreign Governments 0.1 — 2.4 (0.9) 2.5 (0.9) Corporate Securities: Bonds and Notes 608.6 (54.1) 2,638.0 (597.5) 3,246.6 (651.6) Redeemable Preferred Stocks — — 7.4 (1.3) 7.4 (1.3) Collateralized Loan Obligations 21.9 (0.3) 776.2 (29.8) 798.1 (30.1) Other Mortgage- and Asset-backed 25.3 (0.4) 276.5 (57.3) 301.8 (57.7) Total Fixed Maturities $ 1,123.6 $ (80.9) $ 4,955.9 $ (1,068.1) $ 6,079.5 $ (1,149.0) An aging of unrealized losses on the Company’s Investments in Fixed Maturities at December 31, 2022 is presented below. Less Than 12 Months 12 Months or Longer Total (Dollars in Millions) Fair Unrealized Fair Unrealized Fair Unrealized Fixed Maturities: U.S. Government and Government Agencies and Authorities $ 337.3 $ (49.3) $ 126.5 $ (36.5) $ 463.8 $ (85.8) States and Political Subdivisions 854.7 (140.6) 276.8 (97.7) 1,131.5 (238.3) Foreign Governments 0.1 — 2.6 (0.9) 2.7 (0.9) Corporate Securities: Bonds and Notes 2,730.6 (373.9) 424.4 (125.8) 3,155.0 (499.7) Redeemable Preferred Stocks 7.7 (1.0) — — 7.7 (1.0) Collateralized Loan Obligations 568.2 (34.2) 373.9 (26.6) 942.1 (60.8) Other Mortgage- and Asset-backed 205.4 (28.9) 79.5 (21.4) 284.9 (50.3) Total Fixed Maturities $ 4,704.0 $ (627.9) $ 1,283.7 $ (308.9) $ 5,987.7 $ (936.8)
Schedule of Other Investments	The carrying values of the Company’s Other Investments at September 30, 2023 and December 31, 2022 were: (Dollars in Millions) Sep 30, Dec 31, Equity Securities at Modified Cost $ 33.1 $ 38.4 Convertible Securities at Fair Value 45.9 43.3 Real Estate at Depreciated Cost 95.4 93.6 Mortgage Loans 98.5 91.1 Other 0.2 3.5 Total $ 273.1 $ 269.9
Investment Income	Net Investment Income for the nine and three months ended September 30, 2023 and 2022 was: Nine Months Ended Three Months Ended (Dollars in Millions) Sep 30, Sep 30, Sep 30, Sep 30, Investment Income: Interest on Fixed Income Securities $ 259.8 $ 218.4 $ 86.5 $ 76.9 Dividends on Equity Securities Excluding Alternative Investments 3.4 4.3 1.2 1.1 Alternative Investments: Equity Method Limited Liability Investments 8.2 28.0 4.3 (0.6) Limited Liability Investments Included in Equity Securities 14.3 34.9 5.4 8.8 Total Alternative Investments 22.5 62.9 9.7 8.2 Short-term Investments 11.9 1.4 6.0 1.1 Loans to Policyholders 15.6 16.3 5.1 5.5 Real Estate 6.6 7.6 2.3 3.1 Company-Owned Life Insurance 22.6 28.0 6.4 9.9 Other 10.1 5.1 1.8 1.7 Total Investment Income 352.5 344.0 119.0 107.5 Investment Expenses: Real Estate 6.0 5.8 1.7 2.3 Other Investment Expenses 31.4 21.9 10.3 7.4 Total Investment Expenses 37.4 27.7 12.0 9.7 Net Investment Income $ 315.1 $ 316.3 $ 107.0 $ 97.8
Schedule of Realized Gain (Loss)	Gross gains and losses on sales of investments in fixed maturities and gains and losses associated with Ultra-Long Treasury Futures for the nine and three months ended September 30, 2023 and 2022 were: Nine Months Ended Three Months Ended (Dollars in Millions) Sep 30, Sep 30, Sep 30, Sep 30, Fixed Maturities: Gains on Sales $ 2.3 $ 28.0 $ 0.8 $ 14.2 Losses on Sales (10.5) (27.5) (1.2) (23.9) (Losses) Gains on Hedging Activity (29.7) — (29.4) (0.3)
Investments in Fixed Maturities
Debt Securities, Available-for-sale [Line Items]
Schedule of Available-for-sale Securities Reconciliation	The amortized cost and fair values of the Company’s Investments in Fixed Maturities at September 30, 2023 were: Amortized Gross Unrealized Allowance for Expected Credit Losses Fair Value (Dollars in Millions) Gains Losses U.S. Government and Government Agencies and Authorities $ 599.7 $ 0.2 $ (112.7) $ — $ 487.2 States and Political Subdivisions 1,613.9 1.5 (294.7) (0.5) 1,320.2 Foreign Governments 5.1 — (0.9) — 4.2 Corporate Securities: Bonds and Notes 4,047.3 6.8 (651.6) (8.1) 3,394.4 Redeemable Preferred Stocks 9.0 0.1 (1.3) — 7.8 Collateralized Loan Obligations 985.4 0.9 (30.1) — 956.2 Other Mortgage- and Asset-backed 362.1 0.1 (57.7) — 304.5 Investments in Fixed Maturities $ 7,622.5 $ 9.6 $ (1,149.0) $ (8.6) $ 6,474.5 The amortized cost and fair values of the Company’s Investments in Fixed Maturities at December 31, 2022 were: Amortized Gross Unrealized Allowance for Expected Credit Losses Fair Value (Dollars in Millions) Gains Losses U.S. Government and Government Agencies and Authorities $ 612.5 $ 1.3 $ (85.8) $ — $ 528.0 States and Political Subdivisions 1,797.6 10.3 (238.3) (0.7) 1,568.9 Foreign Governments 5.0 — (0.9) — 4.1 Corporate Securities: Bonds and Notes 4,030.3 17.7 (499.7) (8.9) 3,539.4 Redeemable Preferred Stocks 9.0 — (1.0) — 8.0 Collateralized Loan Obligations 1,014.7 — (60.8) — 953.9 Other Mortgage- and Asset-backed 342.7 0.1 (50.3) — 292.5 Investments in Fixed Maturities $ 7,811.8 $ 29.4 $ (936.8) $ (9.6) $ 6,894.8

Derivative Instruments and He_2

Derivative Instruments and Hedging Activities (Tables)	9 Months Ended
	Sep. 30, 2023
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Derivatives Instruments Statements of Financial Performance and Financial Position, Location	The following table presents the derivative instruments, primary underlying risk exposure, gross notional amount, and fair value of the Company’s derivatives: September 30, 2023 December 31, 2022 (Dollars in Millions) Fair Value Fair Value Derivative Instrument Primary Underlying Risk Exposure Gross Notional Amount Assets Liabilities Gross Notional Amount Assets Liabilities Derivatives Designated as Hedging Instruments: Interest Swap Lock Interest Rate Risk $ — $ — $ — $ 5.0 $ — $ 0.4 Derivatives Not Designated or Not Qualifying as Hedging Instruments: Treasury Futures Interest Rate Risk $ 202.5 $ — $ 15.6 $ — $ — $ — Reverse Treasury Lock Interest Rate Risk $ — $ — $ — $ 100.0 $ 1.7 $ —

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	3 Months Ended	9 Months Ended
	Mar. 31, 2023	Sep. 30, 2023	Sep. 30, 2022
Fair Value Disclosures [Abstract]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis		The valuation of assets and liabilities measured at fair value in Company’s Condensed Consolidated Balance Sheets at September 30, 2023 is summarized below. Fair Value Measurements (Dollars in Millions) Quoted Prices Significant Other Significant Measured at Net Asset Value Total Fair Value Assets: Fixed Maturities: U.S. Government and Government Agencies and Authorities $ 94.4 $ 392.8 $ — $ — $ 487.2 States and Political Subdivisions — 1,320.1 0.1 — 1,320.2 Foreign Governments — 4.2 — — 4.2 Corporate Securities: Bonds and Notes — 3,212.0 182.4 — 3,394.4 Redeemable Preferred Stock — 1.2 6.6 — 7.8 Collateralized Loan Obligations — 956.2 — — 956.2 Other Mortgage and Asset-backed — 299.7 4.8 — 304.5 Total Investments in Fixed Maturities 94.4 6,186.2 193.9 — 6,474.5 Equity Securities at Fair Value: Preferred Stocks: Finance, Insurance and Real Estate — 19.9 — — 19.9 Other Industries — 8.4 3.3 — 11.7 Common Stocks: Finance, Insurance and Real Estate 0.6 — — — 0.6 Other Industries 0.2 — 0.4 — 0.6 Other Equity Interests: Exchange Traded Funds 7.1 — — — 7.1 Limited Liability Companies and Limited Partnerships — — — 193.5 193.5 Total Investments in Equity Securities at Fair Value 7.9 28.3 3.7 193.5 233.4 Other Investments: Convertible Securities at Fair Value — 45.9 — — 45.9 Total Assets $ 102.3 $ 6,260.4 $ 197.6 $ 193.5 $ 6,753.8 Liabilities: Accrued Expenses and Other Liabilities: Derivative Instruments Not Designated as Cash Flow Hedges $ — $ 15.6 $ — $ — $ 15.6 Total Liabilities $ — $ 15.6 $ — $ — $ 15.6	The valuation of assets measured at fair value in the Company’s Consolidated Balance Sheets at December 31, 2022 is summarized below. Fair Value Measurements (Dollars in Millions) Quoted Prices Significant Other Significant Measured at Net Asset Value Total Fair Value Assets: Fixed Maturities: U.S. Government and Government Agencies and Authorities $ 103.6 $ 424.4 $ — $ — $ 528.0 States and Political Subdivisions — 1,568.9 — — 1,568.9 Foreign Governments — 4.1 — — 4.1 Corporate Securities: Bonds and Notes — 3,323.4 216.0 — 3,539.4 Redeemable Preferred Stocks — 1.2 6.8 — 8.0 Collateralized Loan Obligations — 953.9 — — 953.9 Other Mortgage and Asset-backed — 287.4 5.1 — 292.5 Total Investments in Fixed Maturities 103.6 6,563.3 227.9 — 6,894.8 Equity Securities at Fair Value: Preferred Stocks: Finance, Insurance and Real Estate — 29.0 — — 29.0 Other Industries — 9.2 1.6 — 10.8 Common Stocks: Finance, Insurance and Real Estate 0.9 — — — 0.9 Other Industries 0.3 0.4 0.5 — 1.2 Other Equity Interests: Exchange Traded Funds 12.2 — — — 12.2 Limited Liability Companies and Limited Partnerships — — — 189.1 189.1 Total Investments in Equity Securities at Fair Value 13.4 38.6 2.1 189.1 243.2 Other Investments: Convertible Securities at Fair Value — 43.3 — — 43.3 Other Assets: Derivative Instruments Not Designated as Hedges — 1.7 — — 1.7 Total Assets $ 117.0 $ 6,646.9 $ 230.0 $ 189.1 $ 7,183.0 Liabilities: Accrued Expenses and Other Liabilities: Derivative Instruments Designated as Fair Value Hedges $ — $ (0.4) $ — $ — $ (0.4) Total Liabilities $ — $ (0.4) $ — $ — $ (0.4) Note 11 - Fair Value Measurements (Continued) The Company’s investments in Fixed Maturities that are classified as Level 1 primarily consist of U.S. Treasury Bonds and Notes. The Company’s investments in Equity Securities at Fair Value that are classified as Level 1 consist of either investments in publicly-traded common stocks or exchange traded funds. The Company’s investments in Fixed Maturities that are classified as Level 2 primarily consist of investments in corporate bonds, obligations of states and political subdivisions, collateralized loan obligations, and mortgage-backed securities of U.S. government agencies. The Company’s investments in Equity Securities at Fair Value that are classified as Level 2 primarily consist of investments in preferred stocks. The Company’s Derivative Instruments Designated as Fair Value Hedges that are classified as Level 2 primarily consist of hedges against the Company’s available for sale debt securities portfolio. The Company uses a leading, nationally recognized provider of market data and analytics to price the vast majority of the Company’s Level 2 measurements. The provider utilizes evaluated pricing models that vary by asset class and incorporate available trade, bid and other market information. Because many fixed maturity securities do not trade on a daily basis, the provider’s evaluated pricing applications apply available information through processes such as benchmark curves, benchmarking of like securities, sector groupings and matrix pricing to prepare evaluations. In addition, the provider uses model processes to develop prepayment and interest rate scenarios. The pricing provider’s models and processes also take into account market convention. For each asset class, teams of its evaluators gather information from market sources and integrate relevant credit information, perceived market movements and sector news into the evaluated pricing applications and models. The Company generally validates the measurements obtained from its primary pricing provider by comparing them with measurements obtained from one additional pricing provider that provides either prices from recent market transactions, quotes in inactive markets or evaluations based on its own proprietary models.
Fair Value Measurement Inputs and Valuation Techniques	The table below presents quantitative information about the significant unobservable inputs utilized by the Company in determining fair values for fixed maturity investments classified as Level 3 at December 31, 2022. (Dollars in Millions) Unobservable Input Total Fair Value Range of Unobservable Inputs Weighted-average Yield Investment-grade Market Yield $ 56.5 4.6 % - 14.5 % 9.2 % Non-investment-grade: Senior Debt Market Yield 72.9 4.6 - 36.7 10.9 Junior Debt Market Yield 42.1 8.8 - 22.5 15.1 Other Various 56.4 Total Level 3 Fixed Maturity Investments $ 227.9	The table below presents quantitative information about the significant unobservable inputs utilized by the Company in determining fair values for fixed maturity investments classified as Level 3 at September 30, 2023. (Dollars in Millions) Unobservable Input Total Fair Value Range of Unobservable Inputs Weighted-average Yield Investment-grade Market Yield $ 58.7 4.2 % - 16.4 % 9.6 % Non-investment-grade: Senior Debt Market Yield 41.9 11.0 - 36.7 13.8 Junior Debt Market Yield 32.2 12.4 - 22.5 14.6 Other Various 61.1 Total Level 3 Fixed Maturity Investments $ 193.9
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation		Information by security type pertaining to the changes in the fair value of the Company’s investments classified as Level 3 for the nine months ended September 30, 2023 is presented below. Fixed Maturities Equity Securities (Dollars in Millions) Corporate States and Political Sub- divisions Redeemable Other Mortgage- Preferred Total Balance at Beginning of Year $ 216.0 $ — $ 6.8 $ 5.1 $ 2.1 $ 230.0 Total Gains (Losses): Included in Condensed Consolidated Statements of Loss 0.7 — — — 0.1 0.8 Included in Other Comprehensive Income 0.2 — (0.2) (0.3) — (0.3) Purchases 44.0 0.1 — — 1.1 45.2 Settlements — — — — — — Sales (83.4) — — — — (83.4) Transfers into Level 3 5.0 — — — 0.4 5.4 Transfers out of Level 3 (0.1) — — — — (0.1) Balance at End of Period $ 182.4 $ 0.1 $ 6.6 $ 4.8 $ 3.7 $ 197.6 The transfers into and out of Level 3 were due primarily to changes in the availability of market observable inputs. Information by security type pertaining to the changes in the fair value of the Company’s investments classified as Level 3 for the three months ended September 30, 2023 is presented below. Fixed Maturities Equity Securities (Dollars in Millions) Corporate States and Political Sub- divisions Redeemable Other Mortgage- Preferred Total Balance at Beginning of Period $ 187.4 $ — $ 6.7 $ 5.2 $ 2.2 $ 201.5 Total Gains (Losses): Included in Condensed Consolidated Statements of Loss 0.2 — — — 1.5 1.7 Included in Other Comprehensive Income (2.2) — (0.1) (0.4) — (2.7) Purchases 6.1 0.1 — — — 6.2 Settlements — — — — — — Sales (14.1) — — — — (14.1) Transfers into Level 3 5.0 — — — — 5.0 Transfers out of Level 3 — — — — — — Balance at End of Period $ 182.4 $ 0.1 $ 6.6 $ 4.8 $ 3.7 $ 197.6 The transfers into and out of Level 3 were due to changes in the availability of market observable inputs. Note 11 - Fair Value Measurements (Continued) Information by security type pertaining to the changes in the fair value of the Company’s investments classified as Level 3 for the nine months ended September 30, 2022 is presented below. Fixed Maturities Equity Securities (Dollars in Millions) Corporate Redeemable Other Mortgage- Preferred Total Balance at Beginning of Year $ 236.8 $ 6.1 $ 7.0 $ 1.5 $ 251.4 Total (Losses) Gains: Included in Condensed Consolidated Statements of Loss (12.2) — — — (12.2) Included in Other Comprehensive Loss (12.2) (1.3) (1.8) 0.2 (15.1) Purchases 115.1 2.0 — 2.7 119.8 Settlements — — — — — Sales (126.0) — — (1.9) (127.9) Transfers into Level 3 22.9 — — — 22.9 Transfers out of Level 3 (5.7) — — — (5.7) Balance at End of Period $ 218.7 $ 6.8 $ 5.2 $ 2.5 $ 233.2 The transfers into and out of Level 3 were due to changes in the availability of market observable inputs. Information by security type pertaining to the changes in the fair value of the Company’s investments classified as Level 3 for the three months ended September 30, 2022 is presented below. Fixed Maturities Equity Securities (Dollars in Millions) Corporate Redeemable Other Mortgage- Preferred Total Balance at Beginning of Period $ 177.1 $ 6.9 $ 5.6 $ 1.7 $ 191.3 Total (Losses) Gains: Included in Condensed Consolidated Statements of Loss (6.3) — — — (6.3) Included in Other Comprehensive Loss (2.8) (0.1) (0.4) — (3.3) Purchases 93.5 — — 2.7 96.2 Settlements — — — — — Sales (60.4) — — (1.9) (62.3) Transfers into Level 3 17.6 — — — 17.6 Transfers out of Level 3 — — — — — Balance at End of Period $ 218.7 $ 6.8 $ 5.2 $ 2.5 $ 233.2
Fair Value, by Balance Sheet Grouping		Presented below are the carrying values and fair value estimates of financial instruments not carried at fair value. September 30, 2023 December 31, 2022 (Dollars in Millions) Carrying Value Fair Value Carrying Value Fair Value Financial Assets: Loans to Policyholders $ 281.8 $ 281.8 $ 283.4 $ 283.4 Short-term Investments 418.5 418.5 278.4 278.4 Mortgage Loans 98.5 98.5 91.1 91.1 Company-Owned Life Insurance 506.9 506.9 586.5 586.5 Equity Securities at Modified Cost 33.1 33.1 38.4 38.4 Financial Liabilities: Long-term Debt $ 1,388.6 $ 1,158.0 $ 1,386.9 $ 1,195.1 Policyholder Obligations 557.4 557.4 601.0 601.0

Variable Interest Entities (Tab

Variable Interest Entities (Tables)	9 Months Ended
	Sep. 30, 2023
Equity Method Investments and Joint Ventures [Abstract]
Schedule of Variable Interest Entities	The following table presents information regarding activity in the Company’s Alternative Energy Partnership Investments for the nine and three months ended September 30, 2023 and 2022. Nine Months Ended Three Months Ended (Dollars in millions) Sep 30, 2023 Sep 30, 2022 Sep 30, 2023 Sep 30, 2022 Fundings $ — $ — $ — $ — Cash Distribution from Investment 1.5 1.5 0.5 0.6 Income (Loss) on Investments in Alternative Energy Partnership 2.3 (21.2) 0.8 0.4 Income Tax (Recaptures) Credits Recognized (0.1) 3.9 — — Tax (Expense) Benefit Recognized from Alternative Energy Partnership (0.5) 4.1 (0.2) (0.1) The following table represents the carrying value of the associated assets and liabilities and the associated maximum loss exposure of the Alternative Energy Partnership Investments as of September 30, 2023 and December 31, 2022. (Dollars in millions) Sep 30, 2023 Dec 31, 2022 Cash $ 2.8 $ 3.0 Equipment, Net of Depreciation 256.6 261.7 Other Assets 6.9 5.1 Total Unconsolidated Assets 266.4 269.7 Maximum Loss Exposure 17.2 16.3

Other Comprehensive Income (L_2

Other Comprehensive Income (Loss) and Accumulated Other Comprehensive Income (Tables)	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Statement of Comprehensive Income [Abstract]
Schedule of Comprehensive Income	The tables below display the changes in Accumulated Other Comprehensive Loss by component for the three months ended September 30, 2023 and 2022. (Dollars in Millions) Net Unrealized Losses on Other Investments Net Unrealized Losses on Investments with an Allowance for Credit Losses Net Unrecognized Postretirement Benefit Costs Gain on Cash Flow Hedge Change in Discount Rate on Future Life Policyholder Benefits Total Balance as of June 30, 2023 $ (637.6) $ (2.3) $ (38.0) $ 2.7 $ 194.4 $ (480.8) Other Comprehensive (Loss) Income Before Reclassifications (258.7) (0.9) (5.4) — 218.6 (46.4) Amounts Reclassified from Accumulated Other Comprehensive Loss Net of Tax Benefit (Expense) of $0.1, $0.1, $(14.4), $0.0, $0.0 and $(14.2) 0.1 (0.2) 53.9 — — 53.8 Other Comprehensive (Loss) Income Net of Tax Benefit (Expense) of $67.5, $0.8, $(12.6), $0.0, $(58.2), and $(2.5) (258.6) (1.1) 48.5 — 218.6 7.4 Balance as of September 30, 2023 $ (896.2) $ (3.4) $ 10.5 $ 2.7 $ 413.0 $ (473.4)	(Dollars in Millions) Net Unrealized Losses on Other Investments Net Unrealized Losses on Investments with an Allowance for Credit Losses Net Unrecognized Postretirement Benefit Costs Gain on Cash Flow Hedge Change in Discount Rate on Future Life Policyholder Benefits Total Balance as of June 30, 2022 $ (467.3) $ (4.1) $ (52.2) $ 2.8 $ 11.4 $ (509.4) Other Comprehensive (Loss) Income Before Reclassifications (309.1) (0.6) — — 261.4 (48.3) Amounts Reclassified from Accumulated Other Comprehensive Loss Net of Tax Benefit of $4.3, $0.0,$0.0, $0.0, $0.0, and $4.3 (16.0) — (0.1) — — (16.1) Other Comprehensive (Loss) Income Net of Tax Benefit (Expense) of $86.4, $0.2, $0.1, $0.0 $(69.5) and $17.2 (325.1) (0.6) (0.1) — 261.4 (64.4) Balance as of September 30, 2022 $ (792.4) $ (4.7) $ (52.3) $ 2.8 $ 272.8 $ (573.8)	The tables below display the changes in Accumulated Other Comprehensive Loss by component for the nine months ended September 30, 2023 and 2022. (Dollars in Millions) Net Unrealized Losses on Other Investments Net Unrealized Losses on Investments with an Allowance for Credit Losses Net Unrecognized Postretirement Benefit Costs Gain on Cash Flow Hedge Change in Discount Rate on Future Life Policyholder Benefits Total Balance as of January 1, 2023 $ (719.4) $ (2.2) $ (37.2) $ 2.8 $ 241.1 (514.9) Other Comprehensive (Loss) Income Before Reclassifications (183.3) 0.5 (5.4) — 171.9 (16.3) Amounts Reclassified from Accumulated Other Comprehensive Loss Net of Tax (Expense) Benefit of $(1.7), $0.5, $(14.1), $0.0, $0.0 and $(15.3) 6.5 (1.7) 53.1 (0.1) — 57.8 Other Comprehensive (Loss) Income Net of Tax Benefit (Expense) of $47.1, $0.4, $(12.6), $0.0, $(45.7), and $(10.8) (176.8) (1.2) 47.7 (0.1) 171.9 41.5 Balance as of September 30, 2023 $ (896.2) $ (3.4) $ 10.5 $ 2.7 $ 413.0 $ (473.4)	(Dollars in Millions) Net Unrealized Gains (Losses) on Other Investments Net Unrealized Losses on Investments with an Allowance for Credit Losses Net Unrecognized Postretirement Benefit Costs (Loss) Gain on Cash Flow Hedge Change in Discount Rate on Future Life Policyholder Benefits Total Balance as of January 1, 2022 $ 505.8 $ (3.7) $ (52.1) $ (1.9) $ (849.7) $ (401.6) Other Comprehensive (Loss) Income Before Reclassifications (1,281.0) (1.0) — 4.7 1,122.5 (154.8) Amounts Reclassified from Accumulated Other Comprehensive Loss Net of Tax Benefit of $4.5, $0.0, $0.0, $0.0, $0.0 and $4.5 (17.2) — (0.2) — — (17.4) Other Comprehensive (Loss) Income Net of Tax Benefit (Expense) of $345.0, $0.3, $0.1, $(1.2), $(298.4), and $45.8 (1,298.2) (1.0) (0.2) 4.7 1,122.5 (172.2) Balance as of September 30, 2022 $ (792.4) $ (4.7) $ (52.3) $ 2.8 $ 272.8 $ (573.8)

Pension Benefits and Postreti_2

Pension Benefits and Postretirement Benefits Other Than Pensions (Tables)	9 Months Ended
	Sep. 30, 2023
Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Schedule of Defined Benefit Plans Disclosures	The components of Pension Expense for the Pension Plan for the nine and three months ended September 30, 2023 and 2022 were: Nine Months Ended Three Months Ended (Dollars in Millions) Sep 30, Sep 30, Sep 30, Sep 30, Interest Cost on Projected Benefit Obligation $ 8.4 $ 6.5 $ 1.5 $ 2.2 Expected Return on Plan Assets (7.9) (5.6) (1.4) (1.9) Amortization of Prior Service Cost 0.4 0.5 0.1 0.2 Amortization of Net Actuarial Loss — 1.3 — 0.4 Pension Settlement Expense 70.2 — 70.2 — Total Pension Expense $ 71.1 $ 2.7 $ 70.4 $ 0.9
Postretirement Benefits Other than Pensions
Defined Benefit Plan Disclosure [Line Items]
Schedule of Defined Benefit Plans Disclosures	The components of OPEB Benefit for the OPEB Plans for the nine and three months ended September 30, 2023 and 2022 were: Nine Months Ended Three Months Ended (Dollars in Millions) Sep 30, Sep 30, Sep 30, Sep 30, Service Cost $ 0.1 $ 0.1 $ — $ — Interest Cost on Accumulated Postretirement Benefit Obligation 0.3 0.1 0.1 — Amortization of Prior Service Credit (1.0) (1.0) (0.3) (0.3) Amortization of Net Gain (1.3) (1.3) (0.4) (0.5) Total OPEB Benefit $ (1.9) $ (2.1) $ (0.6) $ (0.8)

Policyholder Contract Liabili_2

Policyholder Contract Liabilities (Tables)	9 Months Ended
	Sep. 30, 2023
Insurance [Abstract]
Schedule of Liability for Future Policy Benefits, by Product Segment	Policyholder Obligations at September 30, 2023 and December 31, 2022 were as follows: (Dollars in Millions) Sep 30, Dec 31, FHLB Funding Agreements $ 557.4 $ 601.0 Universal Life-type Policyholder Account Balances 98.9 100.3 Total $ 656.3 $ 701.3
Schedule of Federal Home Loan Bank, Advances, by Branch of FHLB Bank	United Insurance’s liability under the funding agreements with the FHLB of Chicago, the amount of collateral pledged under such agreements and FHLB of Chicago common stock owned by United Insurance at September 30, 2023 and December 31, 2022 is presented below. (Dollars in Millions) Sep 30, Dec 31, Liability under Funding Agreements $ 557.4 $ 601.0 Fair Value of Collateral Pledged 619.1 744.6 FHLB of Chicago Common Stock Owned at Cost 16.6 17.5

Debt (Tables)

Debt (Tables)	9 Months Ended
	Sep. 30, 2023
Debt Disclosure [Abstract]
Schedule of Long-term Debt Instruments	Total amortized cost of Long-term Debt outstanding at September 30, 2023 and December 31, 2022 was: (Dollars in Millions) Sep 30, Dec 31, Senior Notes: 4.350% Senior Notes due February 15, 2025 $ 449.6 $ 449.3 2.400% Senior Notes due September 30, 2030 396.9 396.6 3.800% Senior Notes due February 23, 2032 395.8 395.5 5.875% Fixed-Rate Reset Junior Subordinated Debentures Due 2062 146.3 145.5 Total Long-term Debt Outstanding $ 1,388.6 $ 1,386.9

Leases (Tables)

Leases (Tables)	9 Months Ended
	Sep. 30, 2023
Leases [Abstract]
Lease, Cost	The following table presents operating lease right-of-use assets and lease liabilities. (Dollars in Millions) Sep 30, Dec 31, Operating Lease Right-of-Use Assets $ 34.7 $ 45.1 Operating Lease Liabilities 60.6 72.6 Lease expenses are primarily included in Insurance Expenses in the Condensed Consolidated Statements of Loss. Additional information regarding the Company’s lease cost is presented below. Nine Months Ended Three Months Ended (Dollars in Millions) Sep 30, Sep 30, Sep 30, Sep 30, Lease Cost: Operating Lease Cost $ 11.9 $ 17.2 $ 4.0 $ 5.8 Variable Lease Cost 3.2 0.2 1.0 0.1 Short-Term Lease Cost 1 0.5 3.2 (0.3) 1.0 Total Lease Expense $ 15.6 $ 20.6 $ 4.7 $ 6.9 Less: Sub-Lease Income — 0.1 — — Total Lease Cost $ 15.6 $ 20.5 $ 4.7 $ 6.9 1 Leases with an initial term of twelve months or less are not recorded on the Condensed Consolidated Balance Sheets. Supplemental cash flow information related to the Company’s operating leases for the nine months ended September 30, 2023 and 2022 is as follows: Nine Months Ended (Dollars in Millions) Sep 30, Sep 30, Operating Cash Flows from Operating Lease (Fixed Payments) $ 19.6 $ 19.1 Operating Cash Flows from Operating Lease (Liability Reduction) 17.8 17.1 Right-of-Use Assets Obtained in Exchange for New Operating Lease Liabilities 6.6 10.1 As of September 30, 2023, the Company does not have any finance leases. Note 18 - Leases (Continued) Significant judgments and assumptions for determining lease asset and liability at September 30, 2023 and 2022 are presented below. Nine Months Ended Sep 30, Sep 30, Weighted-average Remaining Lease Term - Finance Leases N/A 0.3 years Weighted-average Remaining Lease Term - Operating Leases 5.6 years 5.6 years Weighted-average Discount Rate - Finance Leases N/A 0.6 % Weighted-average Discount Rate - Operating Leases 4.0 % 3.4 %
Lessee, Operating Lease, Liability, to be Paid, Maturity	Future minimum lease payments under operating leases at September 30, 2023 are presented below. There are no significant future minimum lease payments under finance leases. (Dollars in Millions) Sep 30, 2023 Remainder of 2023 $ 5.7 2024 19.3 2025 14.5 2026 8.5 2027 6.3 2028 and Thereafter 19.1 Total Future Payments $ 73.4 Less Imputed Interest 12.8 Present Value of Minimum Lease Payments $ 60.6

Basis of Presentation and Acc_4

Basis of Presentation and Accounting Policies - AOCI Effects of Adoption (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022	Dec. 31, 2020
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Retained Earnings	$ 982.4	$ 1,366.4
Accumulated Other Comprehensive Loss	$ (473.4)	$ (514.9)
Effect of Retrospective Application of Accounting Standards Update 2018-12 | Pre Adoption Balance
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Retained Earnings			$ 2,071.2
Accumulated Other Comprehensive Loss			680.5
Effect of Retrospective Application of Accounting Standards Update 2018-12 | Adjustments to AOCI
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Retained Earnings			0
Accumulated Other Comprehensive Loss			(1,030.3)
Effect of Retrospective Application of Accounting Standards Update 2018-12 | Adjustments to Retained Earnings for Net Pemiums
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Retained Earnings			(25.1)
Accumulated Other Comprehensive Loss			0
Effect of Retrospective Application of Accounting Standards Update 2018-12 | Post Adoption Balance
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Retained Earnings			2,046.1
Accumulated Other Comprehensive Loss			$ (349.8)

Basis of Presentation and Acc_5

Basis of Presentation and Accounting Policies - Effects of Adoption (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022	Dec. 31, 2021
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Earned Premiums (Changes in Deferred Profit Liability for the Nine and Three Months Ended: 2023 - $51.6 and $15.9; 2022 - $56.8 and $19.1)	$ 1,117.8	$ 1,290.9	$ 3,465.6	$ 3,948.5
Policyholders’ Benefits and Incurred Losses and Loss Adjustment Expenses (Changes in Liability for Future Policyholder Benefits for the Nine and Three Months Ended: 2023 - $8.6 and $6.1; 2022 - $21.9 and $1.6)	975.2	1,085.3	3,011.9	3,359.6
Insurance Expenses	259	300.5	794.4	913
Income Tax Benefit	44.4	13	87	64.8
Net Loss	$ (146.3)	$ (74.8)	$ (323.5)	$ (233.3)
Basic (in dollars per share)	$ (2.28)	$ (1.17)	$ (5.05)	$ (3.66)
Diluted (in dollars per share)	$ (2.28)	$ (1.17)	$ (5.05)	$ (3.66)
Deferred Policy Acquisition Costs	$ 622.2	$ 683.8	$ 622.2	$ 683.8	$ 635.6	$ 688
Deferred Income Tax Assets	258.5		258.5		129
Total Assets	12,549.3		12,549.3		13,313.6
Life and Health	3,098.1		3,098.1		3,276.2
Total Liabilities	10,188.1		10,188.1		10,643
Retained Earnings	982.4		982.4		1,366.4
Accumulated Other Comprehensive Loss	(473.4)		(473.4)		(514.9)
Stockholders' Equity Attributable to Parent	2,361.3		2,361.3		2,670.6
Other Comprehensive Loss Before Income Taxes	8.8	(81.6)	52.3	(218)
Other Comprehensive Income (Loss), Net of Taxes	7.4	(64.4)	41.5	(172.2)
Total Comprehensive Loss	$ (138.9)	(139.2)	$ (282)	(405.5)
Revision of Prior Period, Accounting Standards Update, Adjustment
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Earned Premiums (Changes in Deferred Profit Liability for the Nine and Three Months Ended: 2023 - $51.6 and $15.9; 2022 - $56.8 and $19.1)		(16.1)		(50.8)
Policyholders’ Benefits and Incurred Losses and Loss Adjustment Expenses (Changes in Liability for Future Policyholder Benefits for the Nine and Three Months Ended: 2023 - $8.6 and $6.1; 2022 - $21.9 and $1.6)		(17.1)		(66.5)
Insurance Expenses		(0.8)		0
Income Tax Benefit		(0.4)		(3.3)
Net Loss		$ 1.4		$ 12.4
Basic (in dollars per share)		$ 0.02		$ 0.19
Diluted (in dollars per share)		$ 0.02		$ 0.19
Deferred Policy Acquisition Costs					10
Deferred Income Tax Assets					(60.4)
Total Assets					(50.4)
Life and Health					(277.8)
Total Liabilities					(277.8)
Retained Earnings					(13.7)
Accumulated Other Comprehensive Loss					241.1
Stockholders' Equity Attributable to Parent					227.4
Accounting Standards Update 2018-12
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Earned Premiums (Changes in Deferred Profit Liability for the Nine and Three Months Ended: 2023 - $51.6 and $15.9; 2022 - $56.8 and $19.1)		$ 1,307		$ 3,999.3
Policyholders’ Benefits and Incurred Losses and Loss Adjustment Expenses (Changes in Liability for Future Policyholder Benefits for the Nine and Three Months Ended: 2023 - $8.6 and $6.1; 2022 - $21.9 and $1.6)		1,102.4		3,426.1
Insurance Expenses		301.3		913
Income Tax Benefit		13.4		68.1
Net Loss		$ (76.2)		$ (245.7)
Basic (in dollars per share)		$ (1.19)		$ (3.85)
Diluted (in dollars per share)		$ (1.19)		$ (3.85)
Deferred Policy Acquisition Costs					625.6
Deferred Income Tax Assets					189.4
Total Assets					13,364
Life and Health					3,554
Total Liabilities					10,920.8
Retained Earnings					1,380.1
Accumulated Other Comprehensive Loss					(756)
Stockholders' Equity Attributable to Parent					$ 2,443.2
Other Comprehensive Loss Before Income Taxes		$ (412.5)		$ (1,638.9)
Other Comprehensive Income (Loss), Net of Taxes		(325.8)		$ (1,294.7)
Total Comprehensive Loss		$ (402)

Basis of Presentation and Acc_6

Basis of Presentation and Accounting Policies - Effects of Adoption, Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Change in Discount Rate on Future Life Policyholder Benefits	$ 276.8	$ 330.9	$ 217.6	$ 1,420.9
Other Comprehensive Loss Before Income Taxes	8.8	(81.6)	52.3	(218)
Other Comprehensive Income Tax (Expense) Benefit	(1.4)	17.2	(10.8)	45.8
Other Comprehensive Income (Loss), Net of Taxes	7.4	(64.4)	41.5	(172.2)
Other Comprehensive Income (Loss), before Tax, Portion Attributable to Parent				(405.5)
Total Comprehensive Loss	(138.9)	(139.2)	(282)	(405.5)
Net Loss	$ (146.3)	(74.8)	(323.5)	(233.3)
Change in Deferred Policy Acquisition Costs			13.4	4.2
Insurance Reserves			7.9	(25)
Income Taxes			27.5	(62.9)
Net Cash Used in Operating Activities			$ (104.5)	(170.1)
Effect of Modified Retrospective Application Accounting Standards Update 2018-12
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Change in Discount Rate on Future Life Policyholder Benefits		330.9		1,420.9
Other Comprehensive Loss Before Income Taxes		330.9		1,420.9
Other Comprehensive Income Tax (Expense) Benefit		(69.5)		(298.4)
Other Comprehensive Income (Loss), Net of Taxes		261.4		1,122.5
Other Comprehensive Income (Loss), before Tax, Portion Attributable to Parent				1,134.9
Total Comprehensive Loss		262.8
Net Loss				12.4
Change in Deferred Policy Acquisition Costs				0
Insurance Reserves				(15.7)
Income Taxes				3.3
Net Cash Used in Operating Activities				0
Accounting Standards Update 2018-12
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Change in Discount Rate on Future Life Policyholder Benefits		0		0
Other Comprehensive Loss Before Income Taxes		(412.5)		(1,638.9)
Other Comprehensive Income Tax (Expense) Benefit		86.7		344.2
Other Comprehensive Income (Loss), Net of Taxes		(325.8)		(1,294.7)
Other Comprehensive Income (Loss), before Tax, Portion Attributable to Parent				(1,540.4)
Total Comprehensive Loss		(402)
Net Loss		$ (76.2)		(245.7)
Change in Deferred Policy Acquisition Costs				4.2
Insurance Reserves				(9.3)
Income Taxes				(66.2)
Net Cash Used in Operating Activities				$ (170.1)

Net Income Per Unrestricted S_3

Net Income Per Unrestricted Share - Reconciliation of Numerator and Denominator Used in Calculation (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Schedule of Basic and Diluted Earnings Per Share [Line Items]
Net Loss	$ (146.3)	$ (74.8)	$ (323.5)	$ (233.3)
Dilutive Effect on Income of Equity-based Compensation Equivalent Shares	0	0	0	0
Diluted Net Loss Attributed to Unrestricted Shares	$ (146.3)	$ (74.8)	$ (323.5)	$ (233.3)
Weighted-Average Unrestricted Shares Outstanding (in shares)	64,056,900	63,852,800	64,004,400	63,804,400
Equity-based Compensation Equivalent Shares (in shares)	0	0	0	0
Weighted-Average Unrestricted Shares and Equivalent Shares Outstanding Assuming Dilution (in shares)	64,056,900	63,852,800	64,004,400	63,804,400
Basic (in dollars per share)	$ (2.28)	$ (1.17)	$ (5.05)	$ (3.66)
Diluted (in dollars per share)	$ (2.28)	$ (1.17)	$ (5.05)	$ (3.66)
Common Stock
Schedule of Basic and Diluted Earnings Per Share [Line Items]
Net Loss	$ (146.3)	$ (74.8)	$ (323.5)	$ (233.3)
Participating Awards
Schedule of Basic and Diluted Earnings Per Share [Line Items]
Net Loss	$ 0	$ 0	$ 0	$ 0

Dispositions - Narrative (Detai

Dispositions - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023	Dec. 31, 2022
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Consideration		$ 90
Disposal Group, Disposed of by Sale, Not Discontinued Operations | Reserve National Insurance Company
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Not Discontinued Operation, Gain (Loss) On Disposal, Net Of Tax	$ (1.6)

Intangible Assets, Goodwill a_2

Intangible Assets, Goodwill and Other (Details) $ in Millions	3 Months Ended
	Sep. 30, 2023 USD ($)
Goodwill [Line Items]
Goodwill, Impaired, Accumulated Impairment Loss	$ 49.6
Preferred Property & Casualty Insurance [Member]
Goodwill [Line Items]
Goodwill, net of tax impairment charge	$ 45.5

Business Segments - Earned Prem

Business Segments - Earned Premiums by Product Line (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Segment Reporting Information [Line Items]
Earned Premiums (Changes in Deferred Profit Liability for the Nine and Three Months Ended: 2023 - $51.6 and $15.9; 2022 - $56.8 and $19.1)	$ 1,117.8	$ 1,290.9	$ 3,465.6	$ 3,948.5
Operating Segments | Specialty Property & Casualty Insurance
Segment Reporting Information [Line Items]
Earned Premiums (Changes in Deferred Profit Liability for the Nine and Three Months Ended: 2023 - $51.6 and $15.9; 2022 - $56.8 and $19.1)	890.4	999.5	2,766.9	3,064.8
Operating Segments | Life Insurance
Segment Reporting Information [Line Items]
Earned Premiums (Changes in Deferred Profit Liability for the Nine and Three Months Ended: 2023 - $51.6 and $15.9; 2022 - $56.8 and $19.1)	102.1	142.1	303.6	428.9
Operating Segments | Specialty and Life Insurance
Segment Reporting Information [Line Items]
Earned Premiums (Changes in Deferred Profit Liability for the Nine and Three Months Ended: 2023 - $51.6 and $15.9; 2022 - $56.8 and $19.1)	992.5	1,141.6	3,070.5	3,493.7
Operating Segments | Preferred Property & Casualty Insurance [Member]
Segment Reporting Information [Line Items]
Earned Premiums (Changes in Deferred Profit Liability for the Nine and Three Months Ended: 2023 - $51.6 and $15.9; 2022 - $56.8 and $19.1)	125.3	149.3	395.1	454.8
Operating Segments | Personal Automobile | Specialty Property & Casualty Insurance
Segment Reporting Information [Line Items]
Earned Premiums (Changes in Deferred Profit Liability for the Nine and Three Months Ended: 2023 - $51.6 and $15.9; 2022 - $56.8 and $19.1)	724	858.8	2,278.5	2,666.3
Operating Segments | Commercial Automobile | Specialty Property & Casualty Insurance
Segment Reporting Information [Line Items]
Earned Premiums (Changes in Deferred Profit Liability for the Nine and Three Months Ended: 2023 - $51.6 and $15.9; 2022 - $56.8 and $19.1)	166.4	140.7	488.4	398.5
Operating Segments | Life | Life Insurance
Segment Reporting Information [Line Items]
Earned Premiums (Changes in Deferred Profit Liability for the Nine and Three Months Ended: 2023 - $51.6 and $15.9; 2022 - $56.8 and $19.1)	84.9	84.3	251.9	253.8
Operating Segments | Accident and Health | Life Insurance
Segment Reporting Information [Line Items]
Earned Premiums (Changes in Deferred Profit Liability for the Nine and Three Months Ended: 2023 - $51.6 and $15.9; 2022 - $56.8 and $19.1)	5.8	45.9	17.5	136.8
Operating Segments | Property | Life Insurance
Segment Reporting Information [Line Items]
Earned Premiums (Changes in Deferred Profit Liability for the Nine and Three Months Ended: 2023 - $51.6 and $15.9; 2022 - $56.8 and $19.1)	$ 11.4	$ 11.9	$ 34.2	$ 38.3

Business Segments - Segment Rev

Business Segments - Segment Revenues (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Segment Reporting Information [Line Items]
Earned Premiums (Changes in Deferred Profit Liability for the Nine and Three Months Ended: 2023 - $51.6 and $15.9; 2022 - $56.8 and $19.1)	$ 1,117.8	$ 1,290.9	$ 3,465.6	$ 3,948.5
Net Investment Income	107	97.8	315.1	316.3
Change in Value of Alternative Energy Partnership Investments	0.8	0.4	2.3	(21.2)
Other Income	2.4	4	5.3	7.3
Total Revenues	1,199.4	1,361.5	3,757	4,149.3
Income (Loss) from Change in Fair Value of Equity and Convertible Securities	2.8	(11.2)	6.9	(79.9)
Impairment Gains (Losses)	(1.1)	(8.3)	0.1	(22.1)
Operating Segments
Segment Reporting Information [Line Items]
Total Revenues	1,086.8	1,230.8	3,347.2	3,748.4
Operating Segments | Specialty Property & Casualty Insurance
Segment Reporting Information [Line Items]
Earned Premiums (Changes in Deferred Profit Liability for the Nine and Three Months Ended: 2023 - $51.6 and $15.9; 2022 - $56.8 and $19.1)	890.4	999.5	2,766.9	3,064.8
Net Investment Income	42.7	33.9	125.7	102.8
Change in Value of Alternative Energy Partnership Investments	0.5	0.3	1.3	(10.6)
Other Income	1.6	2.3	3.2	5
Total Revenues	935.2	1,036	2,897.1	3,162
Operating Segments | Preferred Property & Casualty Insurance [Member]
Segment Reporting Information [Line Items]
Earned Premiums (Changes in Deferred Profit Liability for the Nine and Three Months Ended: 2023 - $51.6 and $15.9; 2022 - $56.8 and $19.1)	125.3	149.3	395.1	454.8
Total Revenues	138	161.1	431.7	486
Operating Segments | Life Insurance
Segment Reporting Information [Line Items]
Earned Premiums (Changes in Deferred Profit Liability for the Nine and Three Months Ended: 2023 - $51.6 and $15.9; 2022 - $56.8 and $19.1)	102.1	142.1	303.6	428.9
Net Investment Income	49.4	52.6	146.3	163.9
Change in Value of Alternative Energy Partnership Investments	0.2	0.1	0.6	(5.6)
Other Income	(0.1)	0	(0.4)	(0.8)
Total Revenues	151.6	194.8	450.1	586.4
Segment Reconciling Items
Segment Reporting Information [Line Items]
Income (Loss) from Change in Fair Value of Equity and Convertible Securities	2.8	(11.2)	6.9	(79.9)
Gain (Loss) on Sale of Investments	(30.3)	(12.1)	(38.3)	0.4
Impairment Gains (Losses)			0.1	(22.1)
Net Impairment Gains (Losses) Recognized in Earnings	(1.1)	(8.3)
Other	$ 3.2	$ 1.2	$ 9.4	$ 16.5

Business Segments - Segment Ope

Business Segments - Segment Operating Profit (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Segment Reporting Information [Line Items]
Operating Income (Loss)	$ (39)	$ (40.2)	$ (132)	$ (131.1)
Loss before Income Taxes	(190.8)	(87.8)	(410.6)	(298.1)
Corporate and Other Adjusted Operating Loss From:
Income (Loss) from Change in Fair Value of Equity and Convertible Securities	2.8	(11.2)	6.9	(79.9)
Debt and Equity Securities, Realized Gain (Loss)			(38.3)	0.4
Impairment Gains (Losses)	(1.1)	(8.3)	0.1	(22.1)
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement	(70.2)	0	(70.2)	(3.7)
Loss from Early Extinguishment of Debt	0	0	0	(3.7)
Goodwill, pre tax impairment charge	0	0	(49.6)	0
Loss before Income Taxes	(190.7)	(87.8)	(410.5)	(298.1)
Less: Net Loss attributable to Noncontrolling Interest	(0.1)	0	(0.1)	0
Operating Segments
Segment Reporting Information [Line Items]
Operating Income (Loss)	(25.7)	(23.6)	(90.5)	(98.9)
Operating Segments | Specialty Property & Casualty Insurance
Segment Reporting Information [Line Items]
Operating Income (Loss)	(43.2)	(39.2)	(132.9)	(150.4)
Operating Segments | Preferred Property & Casualty Insurance [Member]
Segment Reporting Information [Line Items]
Operating Income (Loss)	(9.6)	(3.3)	(25.5)	(34.4)
Operating Segments | Life Insurance
Segment Reporting Information [Line Items]
Operating Income (Loss)	17.5	15.6	42.4	51.5
Corporate and Other
Segment Reporting Information [Line Items]
Operating Income (Loss)	(13.3)	(16.6)	(41.5)	(32.2)
Corporate and Other Adjusted Operating Loss From:
Other	(13.3)	(16.6)	(41.5)	(32.2)
Segment Reconciling Items
Corporate and Other Adjusted Operating Loss From:
Income (Loss) from Change in Fair Value of Equity and Convertible Securities	2.8	(11.2)	6.9	(79.9)
Debt and Equity Securities, Realized Gain (Loss)	(30.3)	(12.1)	(38.3)	0.4
Impairment Gains (Losses)			0.1	(22.1)
Acquisition and Disposition Related Transaction, Integration, Restructuring and Other Costs	(43.3)	(12.7)	(101.9)	(27.3)
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement	(55.5)	0	(55.5)	(2.9)
Goodwill, pre tax impairment charge	$ 0	$ 0	$ (45.5)	$ 0

Business Segments - Segment Net

Business Segments - Segment Net Operating Income (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Segment Reporting Information [Line Items]
Segment Net Operating Income (Loss)	$ (27.9)	$ (27)	$ (97.8)	$ (92.9)
Loss from Early Extinguishment of Debt	0	0	0	(3.7)
Goodwill, pre tax impairment charge	0	0	(49.6)	0
Net Loss	(146.3)	(74.8)	(323.5)	(233.3)
Net Loss	(146.4)	(74.8)	(323.6)	(233.3)
Less: Net Loss attributable to Noncontrolling Interest	(0.1)	0	(0.1)	0
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement	(70.2)	0	(70.2)	(3.7)
Operating Segments
Segment Reporting Information [Line Items]
Segment Net Operating Income (Loss)	(18.5)	(14.7)	(65.6)	(66.5)
Operating Segments | Specialty Property & Casualty Insurance
Segment Reporting Information [Line Items]
Segment Net Operating Income (Loss)	(33.2)	(28.7)	(102.4)	(112.3)
Operating Segments | Preferred Property & Casualty Insurance [Member]
Segment Reporting Information [Line Items]
Segment Net Operating Income (Loss)	(7.3)	(2.1)	(19.5)	(25)
Operating Segments | Life Insurance
Segment Reporting Information [Line Items]
Segment Net Operating Income (Loss)	14.7	14	36.8	45.8
Corporate and Other
Segment Reporting Information [Line Items]
Segment Net Operating Income (Loss)	(9.4)	(12.3)	(32.2)	(26.4)
Other	(9.4)	(12.3)	(32.2)	(26.4)
Segment Reconciling Items
Segment Reporting Information [Line Items]
Change in Fair Value of Equity and Convertible Securities	2.3	(8.8)	5.5	(63.1)
Net Realized Investment (Losses) Gains	(22.9)	(9.6)	(30.3)	0.3
Impairment Gains (Losses)	(0.8)	(6.6)	0.1	(17.5)
Acquisition and Disposition Related Transaction, Integration, Restructuring and Other Costs	(34.2)	(20.7)	(80.5)	(32.2)
Goodwill, pre tax impairment charge	0	0	(45.5)	0
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement	$ (55.5)	$ 0	$ (55.5)	$ (2.9)

Property and Casualty Insuran_3

Property and Casualty Insurance Reserves - Reserve Activity (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward]
Gross of Reinsurance at Beginning of Year	$ 2,756.9
Incurred Losses and Loss Adjustment Expenses (“ LAE”) Related to:
Incurred Losses and LAE Related to Prior Years	158.5	$ (22.5)
Paid Losses and LAE Related to:
Property and Casualty Insurance Reserves, Gross of Reinsurance at End of Period	2,724.5
Property, Liability and Casualty Insurance Product Line
Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward]
Gross of Reinsurance at Beginning of Year	2,756.9	2,772.7
Less Reinsurance Recoverables at Beginning of Year	39.6	41.9
Property and Casualty Insurance Reserves, Net of Reinsurance at Beginning of Year	2,717.3	2,730.8
Incurred Losses and Loss Adjustment Expenses (“ LAE”) Related to:
Incurred Losses and LAE Related to Current Year	2,660.5	3,125
Incurred Losses and LAE Related to Prior Years	158.5	(22.5)
Total Incurred Losses and LAE	2,819	3,102.5
Paid Losses and LAE Related to:
Paid Losses and LAE Related to Current Year	1,411.8	1,748.9
Paid Losses and LAE Related to Prior Years	1,428.9	1,406.6
Total Paid Losses and LAE	2,840.7	3,155.5
Property and Casualty Insurance Reserves, Net of Reinsurance at End of Period	2,695.6	2,677.8
Plus Reinsurance Recoverables at End of Period	28.9	42.5
Property and Casualty Insurance Reserves, Gross of Reinsurance at End of Period	$ 2,724.5	$ 2,720.3

Property and Casualty Insuran_4

Property and Casualty Insurance Reserves - Narrative (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred Losses and LAE Related to Prior Years	$ (158.5)	$ 22.5
Personal Automobile
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred Losses and LAE Related to Prior Years	(110.9)	31.6
Preferred Automobile [Member]
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred Losses and LAE Related to Prior Years	(18.3)	(1.9)
Homeowners [Member]
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred Losses and LAE Related to Prior Years	(3.8)	(6.1)
Other Personal Lines [Member]
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred Losses and LAE Related to Prior Years	(3.3)	(5.8)
Commercial Automobile
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred Losses and LAE Related to Prior Years	$ (22.2)	$ (7.5)

Property and Casualty Insuran_5

Property and Casualty Insurance Reserves - Allowance for Credit Losses from Policyholders (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2022	Sep. 30, 2023	Dec. 31, 2022	Dec. 31, 2021
Premium Receivable, Allowance for Credit Loss [Roll Forward]
Premium Receivable, Allowance for Credit Loss, Beginning Balance		$ 13.1
Premium Receivable, Allowance for Credit Loss, Ending Balance	$ 12.5	13.5
Receivables from Policyholders (Allowance for Credit Losses: 2023 - $13.5; 2022 - $13.1)	1,349.1	1,102.6	$ 1,286.6	$ 1,418.7
Receivables from policyholders, net of allowance for expected credit losses		1,102.6	1,286.6
Premium receivables, allowance for credit losses	12.5	13.5	$ 13.1	$ 13.6
Provision for Expected Credit Losses	36.7	32.8
Premium Receivable, Allowance for Credit Loss, Writeoff	$ 37.8	$ 32.4

Liability for Future Policyhold

Liability for Future Policyholder Benefits - Changes in Premiums, Discounts and Benefits (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Jun. 30, 2023	Dec. 31, 2022	Jun. 30, 2022	Dec. 31, 2021
Liability for Future Policy Benefit, by Product Segment [Line Items]
Liability for Future Policy Benefit, Expected Net Premium, before Reinsurance, after Discount Rate Change	$ 686.4	$ 621.8	$ 686.4	$ 621.8
Liability for Future Policy Benefit, Expected Net Premium, Original Discount Rate, before Cash Flow and Reinsurance	742.5	664.5	742.5	664.5
Liability for Future Policy Benefit, Expected Net Premium, Original Discount Rate, before Reinsurance, after Cash Flow Change	710.3	605	710.3	605	$ 738.8		$ 652
Present Value of Expected Future Policyholder benefits	3,330.5	3,441.9	3,330.5	3,441.9
Liability for Future Policy Benefit, Expected Future Policy Benefit, Original Discount Rate, before Cash Flow and Reinsurance	3,909.1	3,829.7	3,909.1	3,829.7
Liability for Future Policy Benefit, Expected Future Benefit, Original Discount Rate, before Reinsurance, after Cash Flow Change	3,884.5	3,795.5	3,884.5	3,795.5	3,906.6		3,819.7
Liability for Future Policy Benefit, after Reinsurance	2,644.1	2,820.1	2,644.1	2,820.1
Term Life Insurance
Liability for Future Policy Benefit, by Product Segment [Line Items]
Net Liability for Future Policyholder Benefits	10,181.5	9,585.4	10,181.5	9,585.4
Term Life Insurance | Effect of Retrospective Application of Accounting Standards Update 2018-12
Liability for Future Policy Benefit, by Product Segment [Line Items]
Liability for Future Policy Benefit, Expected Net Premium, before Reinsurance, after Discount Rate Change					711.7	$ 688.6	646.4	$ 669
Liability for Future Policy Benefit, Expected Net Premium, Original Discount Rate, before Cash Flow and Reinsurance					745.1	728.9	660.3	599.8
Liability for Future Policy Benefit, Expected Net Premium, Cumulative Increase (Decrease) from Cash Flow Change	0	0	0	0
Liability for Future Policy Benefit, Expected Net Premium, Cumulative Increase (Decrease) of Actual Variance from Expected Experience	(18.6)	5.2	(18.6)	5.2	(6.3)		(8.3)
Liability for Future Policy Benefit, Expected Net Premium, Issuance	19.7	30.5	81.6	109.9
Liability for Future Policy Benefit, Expected Net Premium, Interest Income	7.7	5.3	22.2	15.6
Liability for Future Policy Benefit, Expected Net Premium, Net Premium Collected	(23.7)	(23.3)	(71.6)	(66)
AOCI, Liability for Future Policy Benefit, Expected Net Premium, before Tax	(56.1)	(42.7)	(56.1)	(42.7)
Present Value of Expected Future Policyholder benefits					3,635.9	3,561	3,799.4	4,933.1
Liability for Future Policy Benefit, Expected Future Policy Benefit, Original Discount Rate, before Cash Flow and Reinsurance					3,915.1	$ 3,906.2	3,827.6	$ 3,788.1
Liability for Future Policy Benefit, Expected Future Policy Benefit, Cumulative Increase (Decrease) from Cash Flow Change	0	0	0	0
Liability for Future Policy Benefit, Expected Future Policy Benefit, Cumulative Increase (Decrease) of Actual Variance from Expected Experience	(21.7)	7.4	(21.7)	7.4	$ (8.5)		$ (7.9)
Liability for Future Policy Benefit, Expected Future Policy Benefit, Issuance	18.9	30.5	80.8	110
Liability for Future Policy Benefit, Expected Future Policy Benefit, Interest Expense	43	40.7	128.2	122.1
Liability for Future Policy Benefit, Expected Future Policy Benefit, Benefit Payment	(59.4)	(61.2)	(184.4)	(197.9)
AOCI, Liability for Future Policy Benefit, Expected Future Policy Benefit, before Tax	(578.6)	(387.8)	(578.6)	(387.8)
Net Liability for Future Policyholder Benefits	2,644.1	2,820.1	2,644.1	2,820.1
Liability for Future Policy Benefit, Reinsurance Recoverable, after Allowance	$ 0	$ 0	$ 0	$ 0

Liability for Future Policyho_2

Liability for Future Policyholder Benefits - Reconciliation of the Net Liability for Future Benefits to Life and Health Insurance Reserves (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Jun. 30, 2023	Dec. 31, 2022	Jun. 30, 2022	Dec. 31, 2021
Insurance [Abstract]
Present Value of Expected Future Policyholder benefits	$ 3,330,500	$ 3,441,900	$ 3,330,500	$ 3,441,900
Net Liability for Future Policyholder Benefits	2,644,100	2,820,100	2,644,100	2,820,100
Deferred Profit Liability	304,900	249,900	304,900	249,900
A&H and Other Reserves	149,100	149,800	149,100	149,800
Total Life and Health Insurance Reserves	3,098,100	3,219,800	3,098,100	3,219,800
Liability for Future Policy Benefit, by Product Segment [Line Items]
Net Liability for Future Policyholder Benefits	2,644,100	2,820,100	2,644,100	2,820,100
Deferred Profit Liability	304,900	249,900	304,900	249,900
A&H and Other Reserves	149,100	149,800	149,100	149,800
Total Life and Health Insurance Reserves	3,098,100	3,219,800	3,098,100	3,219,800
Term Life Insurance
Insurance [Abstract]
Gross Premiums or Assessments	98,400	100,800	300,700	297,200
Interest Expense	35,400	35,400	106,100	106,500
Liability for Future Policy Benefit, by Product Segment [Line Items]
Net Liability for Future Policyholder Benefits	10,181,500	9,585,400	10,181,500	9,585,400
Liability for Future Policy Benefit, Expected Future Gross Premium, Undiscounted, before Reinsurance	4,446,400	3,801,100	4,446,400	3,801,100
Liability for Future Policy Benefit, Expected Future Gross Premium, Discounted, before Reinsurance	2,748,000	2,585,100	2,748,000	2,585,100
Gross Premiums or Assessments	98,400	100,800	300,700	297,200
Interest Expense	$ 35,400	$ 35,400	$ 106,100	$ 106,500
Liability for Future Policy Benefit, Weighted-Average Interest Accretion Rate	4.57%	4.59%	4.57%	4.59%
Liability for Future Policy Benefit, Current Weighted-Average Discount Rate	5.88%	5.44%	5.88%	5.44%
Term Life Insurance | Effect of Retrospective Application of Accounting Standards Update 2018-12
Insurance [Abstract]
Present Value of Expected Future Policyholder benefits					$ 3,635,900	$ 3,561,000	$ 3,799,400	$ 4,933,100
Liability for Future Policy Benefit, by Product Segment [Line Items]
Net Liability for Future Policyholder Benefits	$ 2,644,100	$ 2,820,100	$ 2,644,100	$ 2,820,100

Deferred Costs, Capitalized, _3

Deferred Costs, Capitalized, Prepaid, and Other Assets (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022	Dec. 31, 2021
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Deferred Policy Acquisition Costs	$ 622.2	$ 683.8	$ 635.6	$ 688
Deferred Policy Acquisition Cost, Capitalization	449.3	530
Deferred Policy Acquisition Costs, Amortization Expense	(453.8)	(528.7)
Deferred Policy Acquisition Cost, Experience Adjustment	$ (8.9)	(5.5)
Disposal Group, Held-for-sale, Not Discontinued Operations
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Disposal Group, Including Discontinued Operation, Deferred Policy Acquisition Cost		38.7
Disposal Group, Held-for-sale, Not Discontinued Operations | Reserve National Insurance Company
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Disposal Group, Including Discontinued Operation, Deferred Policy Acquisition Cost		38.7
Effect of Retrospective Application of Accounting Standards Update 2018-12
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Liability for Future Policy Benefit, Weighted-Average Duration	13 years 9 months 18 days		15 years 6 months
Term Life Insurance
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Deferred Policy Acquisition Cost, Capitalization	$ 42.2	47
Deferred Policy Acquisition Costs, Amortization Expense	(14.7)	(21.5)
Deferred Policy Acquisition Cost, Experience Adjustment	(8.9)	(5.5)
Property and Casualty Insurance Reserves
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Deferred Policy Acquisition Costs	199.1	244.5	$ 231.1	268.7
Deferred Policy Acquisition Cost, Capitalization	407.1	483
Deferred Policy Acquisition Costs, Amortization Expense	(439.1)	(507.2)
Deferred Policy Acquisition Cost, Experience Adjustment	0	0
Life Insurance
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Deferred Policy Acquisition Costs	$ 423.1	$ 439.3	$ 404.5	$ 419.3

Investments - Schedule of Fixed

Investments - Schedule of Fixed Maturities (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022	Sep. 30, 2022	Dec. 31, 2021
Debt Securities, Available-for-sale [Line Items]
Fixed maturities, at amortized cost	$ 7,622.5
Gross unrealized gains	9.6
Gross unrealized loss	(1,149)
Fixed maturities, allowance for credit losses	(8.6)	$ (9.6)	$ 7.5	$ 7.5
Fixed maturities at fair value	6,474.5
Investments in Fixed Maturities
Debt Securities, Available-for-sale [Line Items]
Fixed maturities, at amortized cost		7,811.8
Gross unrealized gains		29.4
Gross unrealized loss		(936.8)
Fixed maturities at fair value		6,894.8
Debt securities, available-for-sale, unrealized loss position, accumulated loss	1,149	936.8
Investments in Fixed Maturities | Investment-grade
Debt Securities, Available-for-sale [Line Items]
Debt securities, available-for-sale, unrealized loss position, accumulated loss	1,120.1	904
U.S. Government and Government Agencies and Authorities
Debt Securities, Available-for-sale [Line Items]
Fixed maturities, at amortized cost	599.7	612.5
Gross unrealized gains	0.2	1.3
Gross unrealized loss	(112.7)	(85.8)
Fixed maturities, allowance for credit losses	0	0
Fixed maturities at fair value	487.2	528
Debt securities, available-for-sale, unrealized loss position, accumulated loss	112.7	85.8
States and Political Subdivisions
Debt Securities, Available-for-sale [Line Items]
Fixed maturities, at amortized cost	1,613.9	1,797.6
Gross unrealized gains	1.5	10.3
Gross unrealized loss	(294.7)	(238.3)
Fixed maturities, allowance for credit losses	(0.5)	(0.7)
Fixed maturities at fair value	1,320.2	1,568.9
Debt securities, available-for-sale, unrealized loss position, accumulated loss	294.7	238.3
Foreign Governments
Debt Securities, Available-for-sale [Line Items]
Fixed maturities, at amortized cost	5.1	5
Gross unrealized gains	0	0
Gross unrealized loss	(0.9)	(0.9)
Fixed maturities, allowance for credit losses	0	0	0.4	0
Fixed maturities at fair value	4.2	4.1
Debt securities, available-for-sale, unrealized loss position, accumulated loss	0.9	0.9
Corporate Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Fixed maturities, at amortized cost	4,047.3	4,030.3
Gross unrealized gains	6.8	17.7
Gross unrealized loss	(651.6)	(499.7)
Fixed maturities, allowance for credit losses	(8.1)	(8.9)	7.1	$ 7.5
Fixed maturities at fair value	3,394.4	3,539.4
Debt securities, available-for-sale, unrealized loss position, accumulated loss	651.6	499.7
Redeemable Preferred Stocks
Debt Securities, Available-for-sale [Line Items]
Fixed maturities, at amortized cost	9	9
Gross unrealized gains	0.1	0
Gross unrealized loss	(1.3)	(1)
Fixed maturities, allowance for credit losses	0	0
Fixed maturities at fair value	7.8	8
Debt securities, available-for-sale, unrealized loss position, accumulated loss	1.3		$ 1
Collateralized Loan Obligations
Debt Securities, Available-for-sale [Line Items]
Fixed maturities, at amortized cost	985.4	1,014.7
Gross unrealized gains	0.9	0
Gross unrealized loss	(30.1)	(60.8)
Fixed maturities, allowance for credit losses	0	0
Fixed maturities at fair value	956.2	953.9
Debt securities, available-for-sale, unrealized loss position, accumulated loss	30.1	60.8
Other Mortgage- and Asset-backed
Debt Securities, Available-for-sale [Line Items]
Fixed maturities, at amortized cost	362.1	342.7
Gross unrealized gains	0.1	0.1
Gross unrealized loss	(57.7)	(50.3)
Fixed maturities, allowance for credit losses	0	0
Fixed maturities at fair value	304.5	292.5
Debt securities, available-for-sale, unrealized loss position, accumulated loss	$ 57.7	$ 50.3

Investments - Narrative (Detail

Investments - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022	Dec. 31, 2021
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-Sale, Maturity, without Single Maturity Date, Fair Value	$ 1,637		$ 1,637
Fixed maturities, allowance for credit losses	(8.6)	$ 7.5	(8.6)	$ 7.5	$ (9.6)	$ 7.5
Equity securities	233.4		233.4		243.2
Equity securities without readily determinable fair value, impairment loss, cumulative amount	7.5		7.5
Other Receivables	223.4		223.4		262.6
Equity Securities, FV-NI, Current	$ 233.4		$ 233.4		243.2
Percentage of Equity Method Limited Liability Investments reported with a lag	2.50%		2.50%
Percentage of Equity Method Limited Liability Investments reported with a One Month Lag	5.50%		5.50%
Company-Owned Life Insurance	$ 506.9		$ 506.9		586.5
Loans to Policyholders	281.8		281.8
Loans to Policyholders	281.8		281.8		283.4
Government National Mortgage Association Certificates and Obligations (GNMA)
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-Sale, Maturity, without Single Maturity Date, Fair Value	231.3		231.3
Federal National Mortgage Association Certificates and Obligations (FNMA)
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-Sale, Maturity, without Single Maturity Date, Fair Value	85.9		85.9
Federal Home Loan Mortgage Corporation Certificates and Obligations (FHLMC)
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-Sale, Maturity, without Single Maturity Date, Fair Value	59.2		59.2
Other Non-Governmental Issuers
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-Sale, Maturity, without Single Maturity Date, Fair Value	1,260.6		1,260.6
Investments in Fixed Maturities
Debt Securities, Available-for-sale [Line Items]
Debt securities, available-for-sale, unrealized loss position, accumulated loss	1,149		1,149		936.8
12 Months or Longer	1,068.1		1,068.1		308.9
Other Receivables	0.9		0.9		5.8
Other liabilities	1		1		25.9
Equity Securities
Debt Securities, Available-for-sale [Line Items]
Other Receivables	20.7		20.7		0
Equity Securities | Fair Value, Measurements, Recurring
Debt Securities, Available-for-sale [Line Items]
Equity securities	233.4		233.4		243.2
Equity Securities, FV-NI, Current	233.4		233.4		243.2
Equity Securities | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value, Measurements, Recurring
Debt Securities, Available-for-sale [Line Items]
Equity securities	7.9		7.9		13.4
Equity Securities, FV-NI, Current	7.9		7.9		13.4
Preferred Stocks | Other Industries | Fair Value, Measurements, Recurring
Debt Securities, Available-for-sale [Line Items]
Equity securities	11.7		11.7		10.8
Equity Securities, FV-NI, Current	11.7		11.7		10.8
Preferred Stocks | Other Industries | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value, Measurements, Recurring
Debt Securities, Available-for-sale [Line Items]
Equity securities	0		0		0
Equity Securities, FV-NI, Current	0		0		0
Common Stock | Other Industries | Fair Value, Measurements, Recurring
Debt Securities, Available-for-sale [Line Items]
Equity securities	0.6		0.6		1.2
Equity Securities, FV-NI, Current	0.6		0.6		1.2
Common Stock | Other Industries | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value, Measurements, Recurring
Debt Securities, Available-for-sale [Line Items]
Equity securities	0.2		0.2		0.3
Equity Securities, FV-NI, Current	0.2		0.2		0.3
Corporate Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Debt securities, available-for-sale, unrealized loss position, accumulated loss	651.6		651.6		499.7
12 Months or Longer	597.5		597.5		125.8
Fixed maturities, allowance for credit losses	(8.1)	7.1	(8.1)	7.1	(8.9)	$ 7.5
Equity Method Investments
Debt Securities, Available-for-sale [Line Items]
Other Receivables	2.1		2.1		35.2
Other liabilities	0		0
Variable Interest Entity, Not Primary Beneficiary
Debt Securities, Available-for-sale [Line Items]
Variable Interest Entity, Reporting Entity Involvement, Maximum Loss Exposure, Amount	17.2		17.2		16.3
Variable Interest Entity, Funding Investment Commitment, Funding	0	$ 0	0	$ 0
Variable Interest Entity, Not Primary Beneficiary | Equity Method Limited Liability Investments
Debt Securities, Available-for-sale [Line Items]
Outstanding commitments to fund equity method limited liability investments	89.4		89.4
Variable Interest Entity, Not Primary Beneficiary | Alternative Energy Partnership Investments
Debt Securities, Available-for-sale [Line Items]
Outstanding commitments to fund equity method limited liability investments	0		0		0
Investment-grade | Investments in Fixed Maturities
Debt Securities, Available-for-sale [Line Items]
Debt securities, available-for-sale, unrealized loss position, accumulated loss	1,120.1		1,120.1		904
Non-investment-grade | Investments in Fixed Maturities
Debt Securities, Available-for-sale [Line Items]
Debt securities, available-for-sale, unrealized loss position, accumulated loss	$ 28.9		$ 28.9		$ 32.8
Percentage of unrealized loss position to amortized cost basis of available for sale security average	9.40%		9.40%		11%

Investments - Amortized Costs a

Investments - Amortized Costs and Estimated Fair Value (Details) $ in Millions	Sep. 30, 2023 USD ($)
Amortized Cost
Due in One Year or Less	$ 170.8
Debt Securities, Available-for-Sale, Maturity, Allocated and Single Maturity Date, Rolling after One Through Five Years, Amortized Cost	915.2
Debt Securities, Available-for-Sale, Maturity, Allocated and Single Maturity Date, Rolling after 5 through 10 Years, Amortized Cost	1,089.5
Debt Securities, Available-for-Sale, Maturity, Allocated and Single Maturity Date, Rolling after 10 Years, Amortized Cost	3,625.5
Debt Securities, Available-for-Sale, Maturity, without Single Maturity Date, Amortized Cost	1,821.5
Fixed maturities, at amortized cost	7,622.5
Fair Value
Debt Securities, Available-for-Sale, Maturity, Allocated and Single Maturity Date, Rolling within One Year, Fair Value	161.3
Debt Securities, Available-for-Sale, Maturity, Allocated and Single Maturity Date, Rolling after One Through Five Years, Fair Value	872
Debt Securities, Available-for-Sale, Maturity, Allocated and Single Maturity Date, Rolling after 5 through 10 Years, Fair Value	906.1
Debt Securities, Available-for-Sale, Maturity, Allocated and Single Maturity Date, Rolling after 10 Years, Fair Value	2,898.1
Debt Securities, Available-for-Sale, Maturity, without Single Maturity Date, Fair Value	1,637
Debt Securities, Available-for-Sale	$ 6,474.5

Investments - Continuous Unreal

Investments - Continuous Unrealized Loss (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022	Sep. 30, 2022
U.S. Government and Government Agencies and Authorities
Fixed Maturities:
Fair Value	$ 93.4	$ 337.3
Fair Value	381.9	126.5
Fair Value	475.3	463.8
Fixed Maturities:
Unrealized Losses	(4.1)	(49.3)
Unrealized Losses	(108.6)	(36.5)
Unrealized Losses	(112.7)	(85.8)
States and Political Subdivisions
Fixed Maturities:
Fair Value	374.3	854.7
Fair Value	873.5	276.8
Fair Value	1,247.8	1,131.5
Fixed Maturities:
Unrealized Losses	(22)	(140.6)
Unrealized Losses	(272.7)	(97.7)
Unrealized Losses	(294.7)	(238.3)
Foreign Governments
Fixed Maturities:
Fair Value	0.1	0.1
Fair Value	2.4	2.6
Fair Value	2.5	2.7
Fixed Maturities:
Unrealized Losses	0	0
Unrealized Losses	(0.9)	(0.9)
Unrealized Losses	(0.9)	(0.9)
Corporate Debt Securities [Member]
Fixed Maturities:
Fair Value	608.6	2,730.6
Fair Value	2,638	424.4
Fair Value	3,246.6	3,155
Fixed Maturities:
Unrealized Losses	(54.1)	(373.9)
Unrealized Losses	(597.5)	(125.8)
Unrealized Losses	(651.6)	(499.7)
Redeemable Preferred Stocks
Fixed Maturities:
Fair Value	0		$ 7.7
Fair Value	7.4		0
Fair Value	7.4		7.7
Fixed Maturities:
Unrealized Losses	0		(1)
Unrealized Losses	(1.3)		0
Unrealized Losses	(1.3)		$ (1)
Collateralized Loan Obligations
Fixed Maturities:
Fair Value	21.9	568.2
Fair Value	776.2	373.9
Fair Value	798.1	942.1
Fixed Maturities:
Unrealized Losses	(0.3)	(34.2)
Unrealized Losses	(29.8)	(26.6)
Unrealized Losses	(30.1)	(60.8)
Other Mortgage- and Asset-backed
Fixed Maturities:
Fair Value	25.3	205.4
Fair Value	276.5	79.5
Fair Value	301.8	284.9
Fixed Maturities:
Unrealized Losses	(0.4)	(28.9)
Unrealized Losses	(57.3)	(21.4)
Unrealized Losses	(57.7)	(50.3)
Investments in Fixed Maturities
Fixed Maturities:
Fair Value	1,123.6	4,704
Fair Value	4,955.9	1,283.7
Fair Value	6,079.5	5,987.7
Fixed Maturities:
Unrealized Losses	(80.9)	(627.9)
Unrealized Losses	(1,068.1)	(308.9)
Unrealized Losses	(1,149)	(936.8)
Investments in Fixed Maturities | Non-investment-grade
Fixed Maturities:
Unrealized Losses	$ (28.9)	$ (32.8)

Investments - Allowance for Cre

Investments - Allowance for Credit Losses (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Debt Securities, Available-for-sale, Allowance for Credit Loss [Roll Forward]
Beginning of the Year	$ (9.6)	$ 7.5
Additions for Securities for which No Previous Expected Credit Losses were Recognized	2.2	(5.6)
Reduction Due to Sales	(2.2)
Net Increase (Decrease) in Allowance on Securities for which Expected Credit Losses were Previously Recognized	(1)	(5.1)
Debt Securities, Available-for-Sale, Allowance for Credit Loss	(8.6)	7.5
Debt Securities, Available-for-sale, Allowance for Credit Loss, Writeoff	0	(10.7)
Equity securities, FV-NI, unrealized gain (loss)	5.1
Foreign Governments
Debt Securities, Available-for-sale, Allowance for Credit Loss [Roll Forward]
Beginning of the Year	0	0
Additions for Securities for which No Previous Expected Credit Losses were Recognized		(0.4)
Net Increase (Decrease) in Allowance on Securities for which Expected Credit Losses were Previously Recognized		0
Debt Securities, Available-for-Sale, Allowance for Credit Loss	0	0.4
Debt Securities, Available-for-sale, Allowance for Credit Loss, Writeoff		0
Corporate Debt Securities [Member]
Debt Securities, Available-for-sale, Allowance for Credit Loss [Roll Forward]
Beginning of the Year	(8.9)	7.5
Additions for Securities for which No Previous Expected Credit Losses were Recognized	2.2	(5.2)
Reduction Due to Sales	(1.9)
Net Increase (Decrease) in Allowance on Securities for which Expected Credit Losses were Previously Recognized	(1.1)	(5.1)
Debt Securities, Available-for-Sale, Allowance for Credit Loss	(8.1)	7.1
Debt Securities, Available-for-sale, Allowance for Credit Loss, Writeoff	0	$ (10.7)
States and Political Subdivisions
Debt Securities, Available-for-sale, Allowance for Credit Loss [Roll Forward]
Beginning of the Year	(0.7)
Additions for Securities for which No Previous Expected Credit Losses were Recognized	0
Reduction Due to Sales	(0.3)
Net Increase (Decrease) in Allowance on Securities for which Expected Credit Losses were Previously Recognized	0.1
Debt Securities, Available-for-Sale, Allowance for Credit Loss	(0.5)
Debt Securities, Available-for-sale, Allowance for Credit Loss, Writeoff	$ 0

Investments - Schedule of Other

Investments - Schedule of Other Investments (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Investments, Debt and Equity Securities [Abstract]
Convertible Securities at Fair Value	$ 45.9	$ 43.3
Real Estate at Depreciated Cost	95.4	93.6
Mortgage Loans	98.5	91.1
Investments and Other Noncurrent Assets	0.2	3.5
Total	273.1	269.9
Equity Securities at Modified Cost	$ 33.1	$ 38.4

Investments - Net Investment In

Investments - Net Investment Income (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Net Investment Income [Line Items]
Investment income	$ 119	$ 107.5	$ 352.5	$ 344
Investment expenses	12	9.7	37.4	27.7
Net Investment Income	107	97.8	315.1	316.3
Fixed Maturities
Net Investment Income [Line Items]
Investment income	86.5	76.9	259.8	218.4
Equity Securities
Net Investment Income [Line Items]
Investment income	1.2	1.1	3.4	4.3
Total Alternative Investments
Net Investment Income [Line Items]
Investment income	9.7	8.2	22.5	62.9
Equity Method Limited Liability Investments
Net Investment Income [Line Items]
Investment income	4.3	(0.6)	8.2	28
Limited Liability Investments Included in Equity Securities
Net Investment Income [Line Items]
Investment income	5.4	8.8	14.3	34.9
Short-term Investments
Net Investment Income [Line Items]
Investment income	6	1.1	11.9	1.4
Loans to Policyholders
Net Investment Income [Line Items]
Investment income	5.1	5.5	15.6	16.3
Real Estate
Net Investment Income [Line Items]
Investment income	2.3	3.1	6.6	7.6
Investment expenses	1.7	2.3	6	5.8
Other Investment Expenses
Net Investment Income [Line Items]
Investment expenses	10.3	7.4	31.4	21.9
Universal Life-type Policyholder Account Balances
Net Investment Income [Line Items]
Investment income	1.8	1.7	10.1	5.1
Cash Surrender Value
Net Investment Income [Line Items]
Investment income	$ 6.4	$ 9.9	$ 22.6	$ 28

Investments - Net Realized Gain

Investments - Net Realized Gains on Sales of Investments (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Fixed Maturities
Net Investment Income [Line Items]
Gains on Sales	$ 0.8	$ 14.2	$ 2.3	$ 28
Losses on Sales	(1.2)	(23.9)	(10.5)	(27.5)
Derivative
Net Investment Income [Line Items]
Gain (Loss) on Hedging Activity	$ (29.4)	$ (0.3)	$ (29.7)	$ 0

Derivative Instruments and He_3

Derivative Instruments and Hedging Activities (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Derivative [Line Items]
Derivative Assets (Liabilities), at Fair Value, Net	$ 0
Not Designated as Hedging Instrument
Derivative [Line Items]
Derivative Assets (Liabilities), at Fair Value, Net	15.6	$ 1.7
Fair Value Hedging | Designated as Hedging Instrument
Derivative [Line Items]
Derivative Assets (Liabilities), at Fair Value, Net		0.4
Interest Rate Swap | Fair Value Hedging | Designated as Hedging Instrument
Derivative [Line Items]
Derivative, Notional Amount	0	5
Treasury Lock | Not Designated as Hedging Instrument
Derivative [Line Items]
Derivative, Notional Amount	202.5	0
Reverse Treasury Lock | Not Designated as Hedging Instrument
Derivative [Line Items]
Derivative, Notional Amount	$ 0	$ 100

Fair Value Measurements - Fair

Fair Value Measurements - Fair Value Inputs (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Jun. 30, 2023	Dec. 31, 2022	Jun. 30, 2022	Dec. 31, 2021
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	$ 6,474,500,000		$ 6,474,500,000			$ 6,894,800,000
Equity securities	233,400,000		233,400,000			243,200,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	6,200,000	$ 96,200,000	45,200,000	$ 119,800,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3	5,000,000	17,600,000	5,400,000	22,900,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	197,600,000	233,200,000	197,600,000	233,200,000	$ 201,500,000	230,000,000	$ 191,300,000	$ 251,400,000
Included in Condensed Consolidated Statement of Operations	1,700,000	(6,300,000)	800,000	(12,200,000)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	0	0	(100,000)	(5,700,000)
Included in Other Comprehensive Income (Loss)	(2,700,000)	(3,300,000)	(300,000)	(15,100,000)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements	0	0	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales	(14,100,000)	(62,300,000)	(83,400,000)	(127,900,000)
Fair Value, Equity Securities FV-NI, Entities That Calculate Net Asset Value Per Share, Unfunded Commitments	0		0			0
Fair Value, Equity Method Investments, Entities That Calculate Net Asset Value Per Share, Unfunded Commitments	89,400,000		89,400,000			95,900,000
Other Funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Alternative Investments, Entities That Calculate Net Asset Value Per Share, Unfunded Commitments	0		0			200,000
Fair Value, Equity Method Investments, Entities That Calculate Net Asset Value Per Share, Unfunded Commitments	0		0			0
Equity Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	0	2,700,000	1,100,000	2,700,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3	0	0	400,000	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	3,700,000	2,500,000	3,700,000	2,500,000	2,200,000	2,100,000	1,700,000	1,500,000
Included in Condensed Consolidated Statement of Operations	1,500,000	0	100,000	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	0		0	0
Included in Other Comprehensive Income (Loss)	0	0	0	200,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements	0	0	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales	0	(1,900,000)	0	(1,900,000)
States and Political Subdivisions
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	100,000		100,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3	0		0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	100,000		100,000			0
Included in Condensed Consolidated Statement of Operations	0		0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	0		0
Included in Other Comprehensive Income (Loss)	0		0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements	0		0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales	0		0
Redeemable Preferred Stocks
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	0	0	0	2,000,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3		0	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	6,600,000	6,800,000	6,600,000	6,800,000	$ 6,700,000	6,800,000	$ 6,900,000	$ 6,100,000
Included in Condensed Consolidated Statement of Operations	0	0	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3		0	0	0
Included in Other Comprehensive Income (Loss)	(100,000)	(100,000)	(200,000)	(1,300,000)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements	0	0	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales	0	$ 0	0	$ 0
Fair Value Measured at Net Asset Value Per Share
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Assets	440,100,000		440,100,000			430,700,000
Fair Value, Alternative Investments, Entities That Calculate Net Asset Value Per Share, Unfunded Commitments	103,300,000		103,300,000			96,300,000
Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Convertible debt at fair value	45,900,000		45,900,000			43,300,000
Total Assets	6,753,800,000		6,753,800,000			7,183,000,000
Derivative Asset						1,700,000
Liabilities, Fair Value Disclosure	(15,600,000)		(15,600,000)			400,000
Fair Value, Measurements, Recurring | Investments in Fixed Maturities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	6,474,500,000		6,474,500,000			6,894,800,000
Fair Value, Measurements, Recurring | U.S. Government and Government Agencies and Authorities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	487,200,000		487,200,000			528,000,000
Fair Value, Measurements, Recurring | States and Political Subdivisions
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	1,320,200,000		1,320,200,000			1,568,900,000
Fair Value, Measurements, Recurring | Foreign Governments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	4,200,000		4,200,000			4,100,000
Fair Value, Measurements, Recurring | Bonds and Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	3,394,400,000		3,394,400,000			3,539,400,000
Fair Value, Measurements, Recurring | Redeemable Preferred Stocks
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	7,800,000		7,800,000			8,000,000
Fair Value, Measurements, Recurring | Collateralized Loan Obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	956,200,000		956,200,000			953,900,000
Fair Value, Measurements, Recurring | Other Mortgage- and Asset-backed
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	304,500,000		304,500,000			292,500,000
Fair Value, Measurements, Recurring | Equity Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	233,400,000		233,400,000			243,200,000
Fair Value, Measurements, Recurring | Exchange Traded Funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	7,100,000		7,100,000			12,200,000
Fair Value, Measurements, Recurring | Limited Liability Companies and Limited Partnerships
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	193,500,000		193,500,000			189,100,000
Fair Value, Measurements, Recurring | Designated as Hedging Instrument
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset						(400,000)
Derivative Liability	(15,600,000)		(15,600,000)
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Convertible debt at fair value	0		0
Total Assets	102,300,000		102,300,000			117,000,000
Convertible Securities, Fair Value Disclosures						0
Derivative Asset						0
Liabilities, Fair Value Disclosure	0		0			0
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Investments in Fixed Maturities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	94,400,000		94,400,000			103,600,000
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | U.S. Government and Government Agencies and Authorities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	94,400,000		94,400,000			103,600,000
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | States and Political Subdivisions
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	0		0			0
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Foreign Governments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	0		0			0
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Bonds and Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	0		0			0
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Redeemable Preferred Stocks
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	0		0
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Redeemable Preferred Stocks
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value						0
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Collateralized Loan Obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	0		0			0
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Other Mortgage- and Asset-backed
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	0		0			0
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Equity Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	7,900,000		7,900,000			13,400,000
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Exchange Traded Funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	7,100,000		7,100,000			12,200,000
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Limited Liability Companies and Limited Partnerships
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	0		0			0
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Designated as Hedging Instrument
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Liability	0		0			0
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Convertible debt at fair value	45,900,000		45,900,000			43,300,000
Total Assets	6,260,400,000		6,260,400,000			6,646,900,000
Derivative Asset						1,700,000
Derivative Liability	15,600,000		15,600,000			(400,000)
Liabilities, Fair Value Disclosure	(15,600,000)		(15,600,000)			(400,000)
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Investments in Fixed Maturities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	6,186,200,000		6,186,200,000			6,563,300,000
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | U.S. Government and Government Agencies and Authorities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	392,800,000		392,800,000			424,400,000
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | States and Political Subdivisions
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	1,320,100,000		1,320,100,000			1,568,900,000
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Foreign Governments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	4,200,000		4,200,000			4,100,000
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Bonds and Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	3,212,000,000		3,212,000,000			3,323,400,000
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Redeemable Preferred Stocks
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	1,200,000		1,200,000
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Redeemable Preferred Stocks
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value						1,200,000
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Collateralized Loan Obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	956,200,000		956,200,000			953,900,000
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Other Mortgage- and Asset-backed
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	299,700,000		299,700,000			287,400,000
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Equity Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	28,300,000		28,300,000			38,600,000
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Exchange Traded Funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	0		0			0
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Limited Liability Companies and Limited Partnerships
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	0		0			0
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Convertible debt at fair value	0		0			0
Total Assets	197,600,000		197,600,000			230,000,000
Derivative Asset						0
Liabilities, Fair Value Disclosure	0		0			0
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | Investments in Fixed Maturities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	193,900,000		193,900,000			227,900,000
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | U.S. Government and Government Agencies and Authorities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	0		0			0
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | States and Political Subdivisions
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	100,000		100,000			0
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | Foreign Governments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	0		0			0
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | Bonds and Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	182,400,000		182,400,000			216,000,000
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | Redeemable Preferred Stocks
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	6,600,000		6,600,000
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | Redeemable Preferred Stocks
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value						6,800,000
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | Collateralized Loan Obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	0		0			0
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | Other Mortgage- and Asset-backed
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	4,800,000		4,800,000			5,100,000
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | Equity Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	3,700,000		3,700,000			2,100,000
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | Exchange Traded Funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	0		0			0
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | Limited Liability Companies and Limited Partnerships
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	0		0			0
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | Designated as Hedging Instrument
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Liability	0		0			0
Finance, Insurance and Real Estate | Fair Value, Measurements, Recurring | Preferred Stocks
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	19,900,000		19,900,000			29,000,000
Finance, Insurance and Real Estate | Fair Value, Measurements, Recurring | Common Stock
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	600,000		600,000			900,000
Finance, Insurance and Real Estate | Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Preferred Stocks
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	0		0			0
Finance, Insurance and Real Estate | Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Common Stock
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	600,000		600,000			900,000
Finance, Insurance and Real Estate | Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Preferred Stocks
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	19,900,000		19,900,000			29,000,000
Finance, Insurance and Real Estate | Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Common Stock
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	0		0			0
Finance, Insurance and Real Estate | Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | Preferred Stocks
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	0		0			0
Finance, Insurance and Real Estate | Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | Common Stock
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	0		0			0
Other Industries | Fair Value, Measurements, Recurring | Preferred Stocks
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	11,700,000		11,700,000			10,800,000
Other Industries | Fair Value, Measurements, Recurring | Common Stock
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	600,000		600,000			1,200,000
Other Industries | Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Preferred Stocks
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	0		0			0
Other Industries | Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Common Stock
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	200,000		200,000			300,000
Other Industries | Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Preferred Stocks
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	8,400,000		8,400,000			9,200,000
Other Industries | Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Common Stock
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	0		0			400,000
Other Industries | Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | Preferred Stocks
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	3,300,000		3,300,000			1,600,000
Other Industries | Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | Common Stock
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	400,000		400,000			500,000
Measured at Net Asset Value | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Convertible debt at fair value	0		0			0
Total Assets	193,500,000		193,500,000			189,100,000
Derivative Asset						0
Liabilities, Fair Value Disclosure	0		0			0
Measured at Net Asset Value | Fair Value, Measurements, Recurring | Investments in Fixed Maturities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	0		0			0
Measured at Net Asset Value | Fair Value, Measurements, Recurring | U.S. Government and Government Agencies and Authorities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	0		0			0
Measured at Net Asset Value | Fair Value, Measurements, Recurring | States and Political Subdivisions
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	0		0			0
Measured at Net Asset Value | Fair Value, Measurements, Recurring | Foreign Governments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	0		0			0
Measured at Net Asset Value | Fair Value, Measurements, Recurring | Bonds and Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	0		0			0
Measured at Net Asset Value | Fair Value, Measurements, Recurring | Redeemable Preferred Stocks
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	0		0
Measured at Net Asset Value | Fair Value, Measurements, Recurring | Redeemable Preferred Stocks
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value						0
Measured at Net Asset Value | Fair Value, Measurements, Recurring | Collateralized Loan Obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	0		0			0
Measured at Net Asset Value | Fair Value, Measurements, Recurring | Other Mortgage- and Asset-backed
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	0		0			0
Measured at Net Asset Value | Fair Value, Measurements, Recurring | Equity Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	193,500,000		193,500,000			189,100,000
Measured at Net Asset Value | Fair Value, Measurements, Recurring | Exchange Traded Funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	0		0			0
Measured at Net Asset Value | Fair Value, Measurements, Recurring | Limited Liability Companies and Limited Partnerships
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	193,500,000		193,500,000			189,100,000
Measured at Net Asset Value | Fair Value, Measurements, Recurring | Designated as Hedging Instrument
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Liability	0		0			0
Measured at Net Asset Value | Finance, Insurance and Real Estate | Fair Value, Measurements, Recurring | Preferred Stocks
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	0		0			0
Measured at Net Asset Value | Finance, Insurance and Real Estate | Fair Value, Measurements, Recurring | Common Stock
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	0		0			0
Measured at Net Asset Value | Other Industries | Fair Value, Measurements, Recurring | Preferred Stocks
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	0		0			0
Measured at Net Asset Value | Other Industries | Fair Value, Measurements, Recurring | Common Stock
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	$ 0		$ 0			$ 0

Fair Value Measurements - Narra

Fair Value Measurements - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Unfunded commitments					$ 192.2
Transfers out of Level 3	$ 0	$ 0	$ 0.1	$ 5.7
Debt Securities, Available-for-Sale	6,474.5		6,474.5		6,894.8
Equity Securities, FV-NI, Current	233.4		233.4		243.2
Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Assets	6,753.8		6,753.8		7,183
Convertible debt at fair value	45.9		45.9		43.3
Derivative Asset					1.7
Total Liabilities	15.6		15.6		(0.4)
Fair Value, Measurements, Recurring | Measured at Net Asset Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Assets	193.5		193.5		189.1
Convertible debt at fair value	0		0		0
Derivative Asset					0
Total Liabilities	0		0		0
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Assets	197.6		197.6		230
Convertible debt at fair value	0		0		0
Derivative Asset					0
Total Liabilities	0		0		0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Assets	102.3		102.3		117
Convertible debt at fair value	0		0
Derivative Asset					0
Total Liabilities	0		0		0
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Assets	6,260.4		6,260.4		6,646.9
Convertible debt at fair value	45.9		45.9		43.3
Derivative Asset					1.7
Derivative Liability	15.6		15.6		(0.4)
Total Liabilities	15.6		15.6		0.4
Limited Liability Companies and Limited Partnerships | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	193.5		193.5		189.1
Limited Liability Companies and Limited Partnerships | Fair Value, Measurements, Recurring | Measured at Net Asset Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	193.5		193.5		189.1
Limited Liability Companies and Limited Partnerships | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Unfunded commitments	192.7		192.7
Limited Liability Companies and Limited Partnerships | Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	0		0		0
Limited Liability Companies and Limited Partnerships | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	0		0		0
Limited Liability Companies and Limited Partnerships | Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	0		0		0
U.S. Government and Government Agencies and Authorities | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	487.2		487.2		528
U.S. Government and Government Agencies and Authorities | Fair Value, Measurements, Recurring | Measured at Net Asset Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	0		0		0
U.S. Government and Government Agencies and Authorities | Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	0		0		0
U.S. Government and Government Agencies and Authorities | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	94.4		94.4		103.6
U.S. Government and Government Agencies and Authorities | Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	392.8		392.8		424.4
States and Political Subdivisions | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	1,320.2		1,320.2		1,568.9
States and Political Subdivisions | Fair Value, Measurements, Recurring | Measured at Net Asset Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	0		0		0
States and Political Subdivisions | Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	0.1		0.1		0
States and Political Subdivisions | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	0		0		0
States and Political Subdivisions | Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	1,320.1		1,320.1		1,568.9
Foreign Governments | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	4.2		4.2		4.1
Foreign Governments | Fair Value, Measurements, Recurring | Measured at Net Asset Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	0		0		0
Foreign Governments | Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	0		0		0
Foreign Governments | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	0		0		0
Foreign Governments | Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	4.2		4.2		4.1
Corporate Debt Securities [Member] | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	3,394.4		3,394.4		3,539.4
Corporate Debt Securities [Member] | Fair Value, Measurements, Recurring | Measured at Net Asset Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	0		0		0
Corporate Debt Securities [Member] | Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	182.4		182.4		216
Corporate Debt Securities [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	0		0		0
Corporate Debt Securities [Member] | Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	3,212		3,212		3,323.4
Redeemable Preferred Stocks | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	7.8		7.8		8
Redeemable Preferred Stocks | Fair Value, Measurements, Recurring | Measured at Net Asset Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	0		0
Redeemable Preferred Stocks | Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	6.6		6.6
Redeemable Preferred Stocks | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	0		0
Redeemable Preferred Stocks | Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	1.2		1.2
Collateralized Loan Obligations | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	956.2		956.2		953.9
Collateralized Loan Obligations | Fair Value, Measurements, Recurring | Measured at Net Asset Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	0		0		0
Collateralized Loan Obligations | Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	0		0		0
Collateralized Loan Obligations | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	0		0		0
Collateralized Loan Obligations | Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	956.2		956.2		953.9
Other Mortgage- and Asset-backed | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	304.5		304.5		292.5
Other Mortgage- and Asset-backed | Fair Value, Measurements, Recurring | Measured at Net Asset Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	0		0		0
Other Mortgage- and Asset-backed | Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	4.8		4.8		5.1
Other Mortgage- and Asset-backed | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	0		0		0
Other Mortgage- and Asset-backed | Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	299.7		299.7		287.4
Investments in Fixed Maturities | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	6,474.5		6,474.5		6,894.8
Investments in Fixed Maturities | Fair Value, Measurements, Recurring | Measured at Net Asset Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	0		0		0
Investments in Fixed Maturities | Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	193.9		193.9		227.9
Investments in Fixed Maturities | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	94.4		94.4		103.6
Investments in Fixed Maturities | Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	6,186.2		6,186.2		6,563.3
Preferred Stocks | Fair Value, Measurements, Recurring | Finance, Insurance and Real Estate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	19.9		19.9		29
Preferred Stocks | Fair Value, Measurements, Recurring | Finance, Insurance and Real Estate | Measured at Net Asset Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	0		0		0
Preferred Stocks | Fair Value, Measurements, Recurring | Other Industries
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	11.7		11.7		10.8
Preferred Stocks | Fair Value, Measurements, Recurring | Other Industries | Measured at Net Asset Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	0		0		0
Preferred Stocks | Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring | Finance, Insurance and Real Estate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	0		0		0
Preferred Stocks | Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring | Other Industries
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	3.3		3.3		1.6
Preferred Stocks | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value, Measurements, Recurring | Finance, Insurance and Real Estate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	0		0		0
Preferred Stocks | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value, Measurements, Recurring | Other Industries
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	0		0		0
Preferred Stocks | Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring | Finance, Insurance and Real Estate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	19.9		19.9		29
Preferred Stocks | Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring | Other Industries
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	8.4		8.4		9.2
Common Stock | Fair Value, Measurements, Recurring | Finance, Insurance and Real Estate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	0.6		0.6		0.9
Common Stock | Fair Value, Measurements, Recurring | Finance, Insurance and Real Estate | Measured at Net Asset Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	0		0		0
Common Stock | Fair Value, Measurements, Recurring | Other Industries
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	0.6		0.6		1.2
Common Stock | Fair Value, Measurements, Recurring | Other Industries | Measured at Net Asset Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	0		0		0
Common Stock | Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring | Finance, Insurance and Real Estate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	0		0		0
Common Stock | Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring | Other Industries
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	0.4		0.4		0.5
Common Stock | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value, Measurements, Recurring | Finance, Insurance and Real Estate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	0.6		0.6		0.9
Common Stock | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value, Measurements, Recurring | Other Industries
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	0.2		0.2		0.3
Common Stock | Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring | Finance, Insurance and Real Estate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	0		0		0
Common Stock | Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring | Other Industries
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	0		0		0.4
Exchange Traded Funds | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	7.1		7.1		12.2
Exchange Traded Funds | Fair Value, Measurements, Recurring | Measured at Net Asset Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	0		0		0
Exchange Traded Funds | Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	0		0		0
Exchange Traded Funds | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	7.1		7.1		12.2
Exchange Traded Funds | Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	0		0		0
Equity Securities | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	233.4		233.4		243.2
Equity Securities | Fair Value, Measurements, Recurring | Measured at Net Asset Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	193.5		193.5		189.1
Equity Securities | Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	3.7		3.7		2.1
Equity Securities | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	7.9		7.9		13.4
Equity Securities | Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	28.3		28.3		38.6
Designated as Hedging Instrument | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset					(0.4)
Derivative Liability	(15.6)		(15.6)
Designated as Hedging Instrument | Fair Value, Measurements, Recurring | Measured at Net Asset Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Liability	0		0		0
Designated as Hedging Instrument | Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Liability	0		0		0
Designated as Hedging Instrument | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Liability	$ 0		$ 0		$ 0

Fair Value Measurements - Quant

Fair Value Measurements - Quantitative Information for Level 3 Inputs (Details) $ in Millions	Sep. 30, 2023 USD ($)	Dec. 31, 2022 USD ($)
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Equity Securities, FV-NI, Current	$ 233.4	$ 243.2
Fair Value, Equity Method Investments, Entities That Calculate Net Asset Value Per Share, Unfunded Commitments	89.4	95.9
Equity Securities, FV-NI	33.1	38.4
Fair Value, Equity Securities FV-NI, Entities That Calculate Net Asset Value Per Share, Unfunded Commitments	0	0
Unfunded commitments		192.2
Mezzanine Debt
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value, Equity Method Investments, Entities That Calculate Net Asset Value Per Share, Unfunded Commitments	45.8	51.6
Fair Value, Alternative Investments, Entities That Calculate Net Asset Value Per Share, Unfunded Commitments	62.8	56
Senior Debt
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value, Equity Method Investments, Entities That Calculate Net Asset Value Per Share, Unfunded Commitments	41.3	42
Fair Value, Alternative Investments, Entities That Calculate Net Asset Value Per Share, Unfunded Commitments	10.5	6
Distressed Debt
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value, Equity Method Investments, Entities That Calculate Net Asset Value Per Share, Unfunded Commitments	0	0
Fair Value, Alternative Investments, Entities That Calculate Net Asset Value Per Share, Unfunded Commitments	13	13
Secondary Transactions
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value, Equity Method Investments, Entities That Calculate Net Asset Value Per Share, Unfunded Commitments	1.7	1.7
Fair Value, Alternative Investments, Entities That Calculate Net Asset Value Per Share, Unfunded Commitments	3.1	4.2
Hedge Funds
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value, Equity Method Investments, Entities That Calculate Net Asset Value Per Share, Unfunded Commitments	0	0
Fair Value, Alternative Investments, Entities That Calculate Net Asset Value Per Share, Unfunded Commitments	0	0
Leveraged Buyout
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value, Equity Method Investments, Entities That Calculate Net Asset Value Per Share, Unfunded Commitments	0.6	0.6
Fair Value, Alternative Investments, Entities That Calculate Net Asset Value Per Share, Unfunded Commitments	7	9
Equity Funds
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value, Equity Method Investments, Entities That Calculate Net Asset Value Per Share, Unfunded Commitments	0	0
Fair Value, Alternative Investments, Entities That Calculate Net Asset Value Per Share, Unfunded Commitments	6.7	7.9
Real Estate Funds
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value, Equity Method Investments, Entities That Calculate Net Asset Value Per Share, Unfunded Commitments	0	0
Other Funds
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value, Equity Method Investments, Entities That Calculate Net Asset Value Per Share, Unfunded Commitments	0	0
Fair Value, Alternative Investments, Entities That Calculate Net Asset Value Per Share, Unfunded Commitments	0	0.2
Alternative Energy Partnership Investments | Variable Interest Entity, Not Primary Beneficiary
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Outstanding commitments to fund equity method limited liability investments	0	0
Real Estate
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value, Alternative Investments, Entities That Calculate Net Asset Value Per Share, Unfunded Commitments	0.2	0
Fair Value, Measurements, Recurring
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total Assets	6,753.8	7,183
Total Liabilities	15.6	(0.4)
Convertible debt at fair value	45.9	43.3
Derivative Asset		1.7
Fair Value, Measurements, Recurring | Designated as Hedging Instrument
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Derivative Liability	15.6
Derivative Asset		(0.4)
Fair Value, Measurements, Recurring | Limited Liability Companies and Limited Partnerships
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Equity Securities, FV-NI, Current	193.5	189.1
Fair Value, Measurements, Recurring | Other Industries | Preferred Stocks
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Equity Securities, FV-NI, Current	11.7	10.8
Fair Value, Measurements, Recurring | Other Industries | Common Stock
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Equity Securities, FV-NI, Current	0.6	1.2
Significant Unobservable Inputs (Level 3) | Limited Liability Companies and Limited Partnerships
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Unfunded commitments	192.7
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total Assets	197.6	230
Total Liabilities	0	0
Convertible debt at fair value	0	0
Derivative Asset		0
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring | Designated as Hedging Instrument
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Derivative Liability	0	0
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring | Limited Liability Companies and Limited Partnerships
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Equity Securities, FV-NI, Current	0	0
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring | Other Industries | Preferred Stocks
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Equity Securities, FV-NI, Current	3.3	1.6
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring | Other Industries | Common Stock
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Equity Securities, FV-NI, Current	0.4	0.5
Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value, Measurements, Recurring
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total Assets	102.3	117
Total Liabilities	0	0
Convertible debt at fair value	0
Derivative Asset		0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value, Measurements, Recurring | Designated as Hedging Instrument
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Derivative Liability	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value, Measurements, Recurring | Limited Liability Companies and Limited Partnerships
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Equity Securities, FV-NI, Current	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value, Measurements, Recurring | Other Industries | Preferred Stocks
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Equity Securities, FV-NI, Current	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value, Measurements, Recurring | Other Industries | Common Stock
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Equity Securities, FV-NI, Current	0.2	0.3
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total Assets	6,260.4	6,646.9
Derivative Liability	(15.6)	0.4
Total Liabilities	15.6	0.4
Convertible debt at fair value	45.9	43.3
Derivative Asset		1.7
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring | Limited Liability Companies and Limited Partnerships
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Equity Securities, FV-NI, Current	0	0
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring | Other Industries | Preferred Stocks
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Equity Securities, FV-NI, Current	8.4	9.2
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring | Other Industries | Common Stock
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Equity Securities, FV-NI, Current	0	0.4
Fair Value Measured at Net Asset Value Per Share
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total Assets	440.1	430.7
Equity Method Investments, Fair Value Disclosure	224.1	217
Alternative Investment	193.5	189.1
Fair Value, Alternative Investments, Entities That Calculate Net Asset Value Per Share, Unfunded Commitments	103.3	96.3
Equity Securities, FV-NI	5.3	8.3
Fair Value Measured at Net Asset Value Per Share | Mezzanine Debt
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Equity Method Investments, Fair Value Disclosure	123.8	114.3
Alternative Investment	121.9	106
Fair Value Measured at Net Asset Value Per Share | Senior Debt
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Equity Method Investments, Fair Value Disclosure	21.7	21.6
Alternative Investment	25.1	21.9
Fair Value Measured at Net Asset Value Per Share | Distressed Debt
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Equity Method Investments, Fair Value Disclosure	8	9.4
Alternative Investment	12.8	12.5
Fair Value Measured at Net Asset Value Per Share | Secondary Transactions
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Equity Method Investments, Fair Value Disclosure	8.2	9.3
Alternative Investment	2.9	3.5
Fair Value Measured at Net Asset Value Per Share | Hedge Funds
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Equity Method Investments, Fair Value Disclosure	0.1	0.5
Alternative Investment	3	18.1
Fair Value Measured at Net Asset Value Per Share | Leveraged Buyout
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Equity Method Investments, Fair Value Disclosure	9.9	8.9
Alternative Investment	21.6	21.6
Fair Value Measured at Net Asset Value Per Share | Equity Funds
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Equity Method Investments, Fair Value Disclosure	1.2	1.2
Alternative Investment	6.1	5.4
Fair Value Measured at Net Asset Value Per Share | Real Estate Funds
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Equity Method Investments, Fair Value Disclosure	41.6	43.3
Fair Value Measured at Net Asset Value Per Share | Other Funds
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Equity Method Investments, Fair Value Disclosure	9.6	8.5
Alternative Investment	0	0.1
Fair Value Measured at Net Asset Value Per Share | Alternative Energy Partnership Investments
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Equity Method Investments, Fair Value Disclosure	17.2	16.3
Fair Value Measured at Net Asset Value Per Share | Real Estate
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Alternative Investment	0.1	0
Measured at Net Asset Value | Fair Value, Measurements, Recurring
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total Assets	193.5	189.1
Total Liabilities	0	0
Convertible debt at fair value	0	0
Derivative Asset		0
Measured at Net Asset Value | Fair Value, Measurements, Recurring | Designated as Hedging Instrument
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Derivative Liability	0	0
Measured at Net Asset Value | Fair Value, Measurements, Recurring | Limited Liability Companies and Limited Partnerships
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Equity Securities, FV-NI, Current	193.5	189.1
Measured at Net Asset Value | Fair Value, Measurements, Recurring | Other Industries | Preferred Stocks
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Equity Securities, FV-NI, Current	0	0
Measured at Net Asset Value | Fair Value, Measurements, Recurring | Other Industries | Common Stock
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Equity Securities, FV-NI, Current	$ 0	$ 0
Senior Debt | Measurement Input, Discount Rate | Non-investment-grade | Market Yield | Minimum | Significant Unobservable Inputs (Level 3)
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Debt instrument, measurement input	0.110	0.046
Senior Debt | Measurement Input, Discount Rate | Non-investment-grade | Market Yield | Maximum | Significant Unobservable Inputs (Level 3)
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Debt instrument, measurement input	0.367	0.367
Senior Debt | Measurement Input, Discount Rate | Non-investment-grade | Market Yield | Weighted-average Yield | Significant Unobservable Inputs (Level 3)
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Debt instrument, measurement input	0.138	0.109
Junior Debt | Measurement Input, Discount Rate | Non-investment-grade | Market Yield | Minimum | Significant Unobservable Inputs (Level 3)
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Debt instrument, measurement input	0.124	0.088
Junior Debt | Measurement Input, Discount Rate | Non-investment-grade | Market Yield | Maximum | Significant Unobservable Inputs (Level 3)
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Debt instrument, measurement input	0.225	0.225
Junior Debt | Measurement Input, Discount Rate | Non-investment-grade | Market Yield | Weighted-average Yield | Significant Unobservable Inputs (Level 3)
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Debt instrument, measurement input	0.146	0.151
Private Placement | Investment-grade | Market Yield | Significant Unobservable Inputs (Level 3)
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total Fair Value	$ 58.7	$ 56.5
Private Placement | Measurement Input, Discount Rate | Investment-grade | Market Yield | Minimum | Significant Unobservable Inputs (Level 3)
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Alternative investment, measurement input	0.042	0.046
Private Placement | Measurement Input, Discount Rate | Investment-grade | Market Yield | Maximum | Significant Unobservable Inputs (Level 3)
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Alternative investment, measurement input	0.164	0.145
Private Placement | Measurement Input, Discount Rate | Investment-grade | Market Yield | Weighted-average Yield | Significant Unobservable Inputs (Level 3)
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Alternative investment, measurement input	0.096	0.092
Senior Debt | Non-investment-grade | Market Yield | Significant Unobservable Inputs (Level 3)
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total Fair Value	$ 41.9	$ 72.9
Junior Debt | Non-investment-grade | Market Yield | Significant Unobservable Inputs (Level 3)
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total Fair Value	32.2	42.1
Other | Market Yield | Significant Unobservable Inputs (Level 3)
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total Fair Value	61.1	56.4
Investments in Fixed Maturities | Market Yield | Significant Unobservable Inputs (Level 3)
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total Fair Value	$ 193.9	$ 227.9

Fair Value Measurements - Level

Fair Value Measurements - Level 3 Inputs Reconciliation (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Jun. 30, 2023	Dec. 31, 2022	Jun. 30, 2022	Dec. 31, 2021
Total Losses:
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	$ 197,600,000	$ 233,200,000	$ 197,600,000	$ 233,200,000	$ 201,500,000	$ 230,000,000	$ 191,300,000	$ 251,400,000
Included in Condensed Consolidated Statement of Operations	1,700,000	(6,300,000)	800,000	(12,200,000)
Included in Other Comprehensive Income (Loss)	(2,700,000)	(3,300,000)	(300,000)	(15,100,000)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	6,200,000	96,200,000	45,200,000	119,800,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements	0	0	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales	(14,100,000)	(62,300,000)	(83,400,000)	(127,900,000)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3	5,000,000	17,600,000	5,400,000	22,900,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	0	0	(100,000)	(5,700,000)
Corporate Debt Securities [Member]
Total Losses:
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	182,400,000	218,700,000	182,400,000	218,700,000	187,400,000	216,000,000	177,100,000	236,800,000
Included in Condensed Consolidated Statement of Operations	200,000	(6,300,000)	700,000	(12,200,000)
Included in Other Comprehensive Income (Loss)	(2,200,000)	(2,800,000)	200,000	(12,200,000)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	6,100,000	93,500,000	44,000,000	115,100,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements	0	0	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales	(14,100,000)	(60,400,000)	(83,400,000)	(126,000,000)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3	5,000,000	17,600,000	5,000,000	22,900,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	0	0	(100,000)	(5,700,000)
States and Political Subdivisions
Total Losses:
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	100,000		100,000			0
Included in Condensed Consolidated Statement of Operations	0		0
Included in Other Comprehensive Income (Loss)	0		0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	100,000		100,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements	0		0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales	0		0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3	0		0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	0		0
Redeemable Preferred Stocks
Total Losses:
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	6,600,000	6,800,000	6,600,000	6,800,000	6,700,000	6,800,000	6,900,000	6,100,000
Included in Condensed Consolidated Statement of Operations	0	0	0	0
Included in Other Comprehensive Income (Loss)	(100,000)	(100,000)	(200,000)	(1,300,000)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	0	0	0	2,000,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements	0	0	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales	0	0	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3		0	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3		0	0	0
Other Mortgage- and Asset-backed
Total Losses:
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	4,800,000	5,200,000	4,800,000	5,200,000	5,200,000	5,100,000	5,600,000	7,000,000
Included in Condensed Consolidated Statement of Operations	0	0	0	0
Included in Other Comprehensive Income (Loss)	(400,000)	(400,000)	(300,000)	(1,800,000)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	0	0	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements	0	0	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales	0	0	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3	0	0	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	0	0	0	0
Equity Securities
Total Losses:
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	3,700,000	2,500,000	3,700,000	2,500,000	$ 2,200,000	$ 2,100,000	$ 1,700,000	$ 1,500,000
Included in Condensed Consolidated Statement of Operations	1,500,000	0	100,000	0
Included in Other Comprehensive Income (Loss)	0	0	0	200,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	0	2,700,000	1,100,000	2,700,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements	0	0	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales	0	(1,900,000)	0	(1,900,000)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3	0	$ 0	400,000	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	$ 0		$ 0	$ 0

Fair Value Measurements - Balan

Fair Value Measurements - Balance Sheet Grouping (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Carrying Value
Loans to Policyholders	$ 281.8	$ 283.4
Short-Term Investments	418.5	278.4
418500000	418.5	278.4
Mortgage Loans	98.5	91.1
Long-term Debt	1,388.6	1,386.9
Policyholder Obligations	656.3	701.3
Loans to Policyholders	281.8
Fair Value
Short-term Investments	418.5	278.4
Long-term Debt	1,158	1,195.1
Company-Owned Life Insurance	506.9	586.5
Equity Securities at Modified Cost	33.1	38.4
Equity Securities, FV-NI	33.1	38.4
Fair Value Measured at Net Asset Value Per Share
Fair Value
Equity Securities, FV-NI	5.3	8.3
Fair Value, Alternative Investments, Entities That Calculate Net Asset Value Per Share, Unfunded Commitments	103.3	96.3
Federal Home Loan Bank of Chicago
Fair Value
Policyholder Obligations	557.4	601
Loans to Policyholders
Fair Value
Loans	281.8	283.4
Mortgage Loans
Fair Value
Loans	98.5	91.1
United Insurance Company of America | FHLB Funding Agreements | Federal Home Loan Bank of Chicago
Carrying Value
Policyholder Obligations	$ 557.4	$ 601

Variable Interest Entities (Det

Variable Interest Entities (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Schedule of Equity Method Investments [Line Items]
Income Tax Expense (Benefit)	$ (44,400,000)	$ (13,000,000)	$ (87,000,000)	$ (64,800,000)
Other Assets	488,700,000		488,700,000		$ 530,000,000
Surplus Notes and Guarantee Fund Certificates, Reciprocal Exchange			4,000,000
Variable Interest Entity, Not Primary Beneficiary
Schedule of Equity Method Investments [Line Items]
Variable Interest Entity, Funding Investment Commitment, Funding	0	0	0	0
Proceeds from Equity Method Investment, Distribution	500,000	600,000	1,500,000	1,500,000
Income (Loss) from Equity Method Investments	800,000	400,000	2,300,000	(21,200,000)
Income Tax Credits and Adjustments	0	0	(100,000)	3,900,000
Income Tax Expense (Benefit)	(200,000)	$ (100,000)	(500,000)	$ 4,100,000
Cash and Cash Equivalents, at Carrying Value	2,800,000		2,800,000		3,000,000
Property, Plant and Equipment, Net	256,600,000		256,600,000		261,700,000
Other Assets	6,900,000		6,900,000		5,100,000
Assets	266,400,000		266,400,000		269,700,000
Variable Interest Entity, Reporting Entity Involvement, Maximum Loss Exposure, Amount	$ 17,200,000		$ 17,200,000		$ 16,300,000

Other Comprehensive Income (L_3

Other Comprehensive Income (Loss) and Accumulated Other Comprehensive Income (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Jun. 30, 2023	Dec. 31, 2022	Jun. 30, 2022	Dec. 31, 2021
Stockholders' Equity Attributable to Parent	$ 2,361.3		$ 2,361.3			$ 2,670.6
Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax					$ (38)	(37.2)		$ (52.1)
AOCI, Cash Flow Hedge, Cumulative Gain (Loss), after Tax					2.7	2.8		(1.9)
AOCI, Liability for Future Policy Benefit, Expected Future Policy Benefit, before Tax	241.1	$ (849.7)	241.1	$ (849.7)	194.4		$ 11.4
AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-sale, Parent [Member]
Stockholders' Equity Attributable to Parent	(3.4)	(4.7)	(3.4)	(4.7)	(2.3)	(2.2)	(4.1)	(3.7)
OCI, before Reclassifications, Net of Tax, Attributable to Parent	(0.9)	(0.6)	0.5	(1)
Reclassification from AOCI, Current Period, Tax	0.1	0	0.5	0
Reclassification from AOCI, Current Period, Net of Tax, Attributable to Parent	(0.2)	0	(1.7)	0
Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent	0.8	0.2	0.4	0.3
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	(1.1)	(0.6)	(1.2)	(1)
Accumulated Other Comprehensive Loss
Stockholders' Equity Attributable to Parent	(473.4)	(573.8)	(473.4)	(573.8)	(480.8)	(514.9)	(509.4)	(401.6)
OCI, before Reclassifications, Net of Tax, Attributable to Parent	(46.4)	(48.3)	(16.3)	(154.8)
Reclassification from AOCI, Current Period, Tax	(14.2)		(15.3)	4.5
Reclassification from AOCI, Current Period, Net of Tax, Attributable to Parent	53.8	(16.1)	57.8	(17.4)
Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent	(2.5)	17.2	(10.8)	45.8
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	7.4	(64.4)	41.5	(172.2)
Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]
Stockholders' Equity Attributable to Parent	10.5	(52.3)	10.5	(52.3)			52.2
OCI, before Reclassifications, Net of Tax, Attributable to Parent	(5.4)	0		0
Reclassification from AOCI, Current Period, Tax	(14.4)	0	(14.1)	0
Reclassification from AOCI, Current Period, Net of Tax, Attributable to Parent	53.9	(0.1)	53.1	(0.2)
Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent	(12.6)	0.1	(12.6)	0.1
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	48.5	(0.1)	47.7	(0.2)
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent [Member]
Stockholders' Equity Attributable to Parent	2.7	2.8	2.7	2.8			2.8
OCI, before Reclassifications, Net of Tax, Attributable to Parent	0	0	0	4.7
Reclassification from AOCI, Current Period, Tax	0	0	0	0
Reclassification from AOCI, Current Period, Net of Tax, Attributable to Parent	0	0	(0.1)	0
Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent	0	0	0	(1.2)
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	0	0	(0.1)	4.7
AOCI, Gain (Loss), Debt Securities, Available-for-sale, with Allowance for Credit Loss, Parent
Stockholders' Equity Attributable to Parent	(896.2)	(792.4)	(896.2)	(792.4)	$ (637.6)	$ (719.4)	$ (467.3)	$ 505.8
OCI, before Reclassifications, Net of Tax, Attributable to Parent	(258.7)	(309.1)	(183.3)	(1,281)
Reclassification from AOCI, Current Period, Tax	0.1		(1.7)	4.5
Reclassification from AOCI, Current Period, Net of Tax, Attributable to Parent	0.1	(16)	6.5	(17.2)
Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent	67.5	86.4	47.1	345
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	(258.6)	(325.1)	(176.8)	(1,298.2)
AOCI, Liability for Future Policy Benefit, Parent
Stockholders' Equity Attributable to Parent	413	272.8	413	272.8
OCI, before Reclassifications, Net of Tax, Attributable to Parent	218.6	261.4	171.9	1,122.5
Reclassification from AOCI, Current Period, Tax	0	0	0	0
Reclassification from AOCI, Current Period, Net of Tax, Attributable to Parent	0	0		0
Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent	(58.2)	(69.5)	(45.7)	(298.4)
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	$ 218.6	$ 261.4	$ 171.9	$ 1,122.5

Stockholders_ Equity - Narrativ

Stockholders’ Equity - Narrative (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022	Dec. 31, 2021	May 06, 2020	Aug. 06, 2014
Class of Stock [Line Items]
Remaining authorized repurchase amount					$ 171,600,000	$ 333,300,000		$ 133,300,000
Weighted-average Remaining Lease Term - Finance Leases		3 months 18 days		3 months 18 days
Weighted-average Remaining Lease Term - Operating Leases	5 years 7 months 6 days	5 years 7 months 6 days	5 years 7 months 6 days	5 years 7 months 6 days
Weighted-average Discount Rate - Finance Leases		0.60%		0.60%
Weighted-average Discount Rate - Operating Leases	4%	3.40%	4%	3.40%
Value of additional shares authorized to be repurchased							$ 200,000,000
Employee Stock Purchase Plan | Employee Stock Option
Class of Stock [Line Items]
Price per share (in dollars per share)	$ 35.73	$ 35.07	$ 35.73	$ 35.07
Compensation costs	$ 200,000		$ 500,000	$ 600,000
Employee Stock Purchase Plan | Share-based Payment Arrangement
Class of Stock [Line Items]
Shares issued under employee stock purchase plan (in shares)	24,000	31,000	68,000	79,000
Price per share (in dollars per share)	$ 40.61	$ 40.54	$ 40.61	$ 40.54

Pension Benefits and Postreti_3

Pension Benefits and Postretirement Benefits Other Than Pensions - Narrative (Details) $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2023 USD ($) employees	Sep. 30, 2023 USD ($)
Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Number of participants and beneficiaries | employees	3,100
Percentage of compensation (as a percent)		3%
Payments to participants of pension plan	$ 90
Contract purchase amount	205.7	$ 205.7
Noncash settlement charge	70.2
Net assets of pension plan	16	$ 16
Noncash settlement charge, after tax	$ 55.5
Postretirement Benefits Other than Pensions
Defined Benefit Plan Disclosure [Line Items]
Number of retired employees covered | employees	300
Number of active employees covered | employees	500

Pension Benefits and Postreti_4

Pension Benefits and Postretirement Benefits Other Than Pensions - Pension Income (Details) - Pension Plans - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Defined Benefit Plan Disclosure [Line Items]
Interest Cost on Projected Benefit Obligation	$ 1.5	$ 2.2	$ 8.4	$ 6.5
Expected Return on Plan Assets	(1.4)	(1.9)	(7.9)	(5.6)
Amortization of Prior Service Credit	0.1	0.2	0.4	0.5
Amortization of Net Actuarial Loss	0	0.4	0	1.3
Defined Benefit Plan, Plan Assets, Payment for Settlement	70.2	0	70.2	0
Total Pension Expense	$ 70.4	$ 0.9	$ 71.1	$ 2.7

Pension Benefits and Postreti_5

Pension Benefits and Postretirement Benefits Other Than Pensions - Components of OPEB Benefits (Details) - Postretirement Benefits Other than Pensions - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service Cost	$ 0	$ 0	$ 0.1	$ 0.1
Interest Cost on Accumulated Postretirement Benefit Obligation	0.1	0	0.3	0.1
Amortization of Prior Service Credit	(0.3)	(0.3)	(1)	(1)
Amortization of Net Gain	(0.4)	(0.5)	(1.3)	(1.3)
Total Pension Expense	$ (0.6)	$ (0.8)	$ (1.9)	$ (2.1)

Policyholder Contract Liabili_3

Policyholder Contract Liabilities - Policyholder Contract Liabilities (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Policyholder Obligations	$ 656.3	$ 701.3
United Insurance Company of America | Federal Home Loan Bank of Chicago
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
FHLB of Chicago Common Stock Owned at Cost	16.6	17.5
FHLB Funding Agreements | United Insurance Company of America | Federal Home Loan Bank of Chicago
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Policyholder Obligations	557.4	601
Universal Life-type Policyholder Account Balances
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Policyholder Obligations	$ 98.9	$ 100.3

Policyholder Contract Liabili_4

Policyholder Contract Liabilities - Narrative (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2023	Dec. 31, 2022
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Policyholder Account Balance, Weighted Average Crediting Rate	5.10%
Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Net	$ 298.2	$ 311.4
Policyholder Account Balance, Cash Surrender Value	97.8	$ 100
United Insurance Company of America | Federal Home Loan Bank of Chicago
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Federal Home Loan Bank, amount of advances	122.5
Payments of FHLBank borrowings	$ 166.1

Policyholder Contract Liabili_5

Policyholder Contract Liabilities - Supplemental Financial Information (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Policyholder Obligations	$ 656.3	$ 701.3
Federal Home Loan Bank of Chicago | United Insurance Company of America
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Fair Value of Collateral Pledged	619.1	744.6
Federal Home Loan Bank of Chicago | United Insurance Company of America | FHLB Funding Agreements
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Policyholder Obligations	$ 557.4	$ 601

Debt - Narrative (Details)

Debt - Narrative (Details) - USD ($)			1 Months Ended	3 Months Ended		9 Months Ended
	Mar. 10, 2022	Jun. 04, 2019	Mar. 31, 2021	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022	Feb. 15, 2022	Sep. 22, 2020	Jun. 08, 2018	Feb. 28, 2015
Debt Instrument [Line Items]
Long-term Debt				$ 1,388,600,000		$ 1,388,600,000		$ 1,386,900,000
Interest and other expenses				14,100,000	$ 14,300,000	42,200,000	$ 41,000,000
Interest paid, including capitalized interest, operating and investing activities				19,900,000	$ 25,000,000	47,200,000	$ 49,400,000
Derivative, Gain on Derivative						5,900,000
Senior Notes, 2.400 Percent Due September 30, 2030
Debt Instrument [Line Items]
Long-term Debt										$ 395,800,000
Senior Notes, 3.800 Percent Due February 23, 2033
Debt Instrument [Line Items]
Long-term Debt									$ 395,100,000
5.875% Fixed-Rate Reset Junior Subordinated Debentures due 2062
Debt Instrument [Line Items]
Long-term Debt	$ 144,700,000
Senior Notes | Senior Notes, 4.35 Percent Due February 15, 2025
Debt Instrument [Line Items]
Long-term Debt				$ 449,600,000		$ 449,600,000		449,300,000
Stated interest rate				4.35%		4.35%
Long-term debt, gross				$ 450,000,000		$ 450,000,000
Face amount of debt												$ 250,000,000
Increase in senior notes			$ 200,000,000
Senior Notes | Senior Notes, 2.400 Percent Due September 30, 2030
Debt Instrument [Line Items]
Long-term Debt				396,900,000		396,900,000		396,600,000
Stated interest rate										2.40%
Long-term debt, gross				400,000,000		400,000,000
Effective interest rate										2.52%
Senior Notes | Senior Notes, 3.800 Percent Due February 23, 2033
Debt Instrument [Line Items]
Long-term Debt				395,800,000		395,800,000		395,500,000
Stated interest rate									3.80%
Long-term debt, gross				400,000,000		400,000,000
Effective interest rate										3.95%
Senior Notes | 5.875% Fixed-Rate Reset Junior Subordinated Debentures due 2062
Debt Instrument [Line Items]
Long-term debt, gross				150,000,000		150,000,000
Senior Notes | Senior Notes, 5.875 Percent Due March 15, 2062
Debt Instrument [Line Items]
Long-term Debt				146,300,000		146,300,000		$ 145,500,000
Junior Debt | Senior Notes, 5.875 Percent Due March 15, 2062
Debt Instrument [Line Items]
Stated interest rate	5.875%
Junior Debt | Senior Notes, 5.875 Percent Due March 15, 2062 | Five-Year Treasury Rate
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	4.14%
Revolving Credit Facility | Notes Payable under Revolving Credit Agreement | Second Amended and Restated Credit Agreement
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity		$ 800,000,000		376,000,000		376,000,000					$ 600,000,000
Increase in revolving credit borrowing capacity		$ 200,000,000
Line of credit facility, amount outstanding				$ 0		$ 0

Debt - Long Term Debt (Details)

Debt - Long Term Debt (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2023	Dec. 31, 2022	Mar. 10, 2022	Feb. 15, 2022	Sep. 22, 2020
Debt Instrument [Line Items]
Long-term Debt	$ 1,388.6	$ 1,386.9
Derivative, Gain (Loss) on Derivative, Net	0.5
Gain (Loss) on Derivative Instruments, Net, Pretax	0.4
Senior Notes, 2.400 Percent Due September 30, 2030
Debt Instrument [Line Items]
Long-term Debt					$ 395.8
Senior Notes, 3.800 Percent Due February 23, 2033
Debt Instrument [Line Items]
Long-term Debt				$ 395.1
5.875% Fixed-Rate Reset Junior Subordinated Debentures due 2062
Debt Instrument [Line Items]
Long-term Debt			$ 144.7
Senior Notes | Senior Notes, 4.35 Percent Due February 15, 2025
Debt Instrument [Line Items]
Long-term Debt	$ 449.6	449.3
Stated interest rate	4.35%
Senior Notes | Senior Notes, 2.400 Percent Due September 30, 2030
Debt Instrument [Line Items]
Long-term Debt	$ 396.9	396.6
Stated interest rate					2.40%
Senior Notes | Senior Notes, 3.800 Percent Due February 23, 2033
Debt Instrument [Line Items]
Long-term Debt	395.8	395.5
Stated interest rate				3.80%
Senior Notes | Senior Notes, 5.875 Percent Due March 15, 2062
Debt Instrument [Line Items]
Long-term Debt	$ 146.3	$ 145.5
Junior Debt | Senior Notes, 5.875 Percent Due March 15, 2062
Debt Instrument [Line Items]
Stated interest rate			5.875%

Leases - Narrative (Details)

Leases - Narrative (Details) $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2023 USD ($)	Sep. 30, 2023 USD ($)
Lessee, Lease, Description [Line Items]
Gain (Loss) on Termination of Lease	$ 14.8	$ 18
Minimum | Building
Lessee, Lease, Description [Line Items]
Lessee, operating lease, term of contract	1 year	1 year
Minimum | Equipment
Lessee, Lease, Description [Line Items]
Lessee, operating lease, term of contract	1 year	1 year
Maximum | Building
Lessee, Lease, Description [Line Items]
Lessee, operating lease, term of contract	15 years	15 years
Maximum | Equipment
Lessee, Lease, Description [Line Items]
Lessee, operating lease, term of contract	5 years	5 years

Leases - Right of Use Assets an

Leases - Right of Use Assets and Liabilities (Details) (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Leases [Abstract]
Operating Lease Right-of-Use Assets	$ 34.7	$ 45.1
Operating Lease Liabilities	$ 60.6	$ 72.6

Leases - Lease Cost (Details)

Leases - Lease Cost (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Lease Cost
Operating Lease Cost	$ 4	$ 5.8	$ 11.9	$ 17.2
Variable Lease, Cost	1	0.1	3.2	0.2
Short-Term Lease Cost	(0.3)	1	0.5	3.2
Total Lease Expense	4.7	6.9	15.6	20.6
Less: Sublease Income	0	0	0	0.1
Lease, Cost	$ 4.7	$ 6.9	$ 15.6	$ 20.5

Leases - Supplemental Cash Flow

Leases - Supplemental Cash Flow Information (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2022	Sep. 30, 2023
Leases [Abstract]
Operating Cash Flows from Operating Lease (Fixed Payments)	$ 19.1	$ 19.6
Operating Cash Flows from Operating Lease (Liability Reduction)	17.1	17.8
Right-of-Use Assets Obtained in Exchange for New Operating Lease Liabilities	$ 10.1	$ 6.6

Leases - Lease Weighted Average

Leases - Lease Weighted Average (Details)	Sep. 30, 2023	Sep. 30, 2022
Leases [Abstract]
Weighted-average Remaining Lease Term - Finance Leases		3 months 18 days
Weighted-average Remaining Lease Term - Operating Leases	5 years 7 months 6 days	5 years 7 months 6 days
Weighted-average Discount Rate - Finance Leases		0.60%
Weighted-average Discount Rate - Operating Leases	4%	3.40%

Leases - Future Minimum Lease P

Leases - Future Minimum Lease Payments Under Finance and Operating Leases (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
Remainder of 2023	$ 5.7
2024	19.3
2025	14.5
2026	8.5
2027	6.3
2028 and Thereafter	19.1
Total Future Payments	73.4
Less Imputed Interest	12.8
Present Value of Minimum Lease Payments	$ 60.6	$ 72.6

Income Taxes - Narrative (Detai

Income Taxes - Narrative (Details) - USD ($)	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Income Tax Disclosure [Abstract]
Unrecognized tax benefits	$ 0
Proceeds from Income Tax Refunds	113,600,000	$ 400,000
Income taxes paid, net	$ 100,000

Uncategorized Items - kmpr-2023

Label	Element	Value
Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, Including Disposal Group and Discontinued Operations	us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	$ 148,200,000