CNA Financial (CNA) 10-Q 4 Nov 24 2024 Q3 Quarterly report Financial data

Cover Page

Cover Page - shares	9 Months Ended
	Sep. 30, 2024	Oct. 31, 2024
Entity Information [Line Items]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2024
Current Fiscal Year End Date	--12-31
Document Transition Report	false
Entity File Number	1-5823
Entity Registrant Name	CNA FINANCIAL CORPORATION
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	36-6169860
Entity Address, Address Line One	151 N. Franklin
Entity Address, Postal Zip Code	60606
Entity Address, City or Town	Chicago,
Entity Address, State or Province	IL
City Area Code	312
Local Phone Number	822-5000
Title of 12(b) Security	Common Stock, Par value $2.50
Trading Symbol	CNA
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
ICFR Auditor Attestation Flag
Entity Shell Company	false
Entity Common Stock, Shares Outstanding (in shares)		270,842,416
Entity Central Index Key	0000021175
Document Fiscal Year Focus	2024
Document Fiscal Period Focus	Q3
Amendment Flag	false
New York Stock Exchange
Entity Information [Line Items]
Security Exchange Name	NYSE
Chicago Stock Exchange
Entity Information [Line Items]
Security Exchange Name	CHX

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations (Unaudited) - USD ($) shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Revenues
Net earned premiums	$ 2,593	$ 2,406	$ 7,532	$ 7,001
Net investment income	626	553	1,853	1,653
Net investment losses	(10)	(38)	(42)	(105)
Non-insurance warranty revenue	401	407	1,212	1,221
Other revenues	8	8	26	22
Total revenues	3,618	3,336	10,581	9,792
Claims, Benefits and Expenses
Insurance claims and policyholders’ benefits (re-measurement loss of $(48), $(41), $(88) and $(75))	2,019	1,826	5,708	5,258
Amortization of deferred acquisition costs	457	426	1,336	1,208
Non-insurance warranty expense	387	386	1,169	1,154
Other operating expenses	362	338	1,077	1,021
Interest	32	34	101	93
Total claims, benefits and expenses	3,257	3,010	9,391	8,734
Income before income tax	361	326	1,190	1,058
Income tax expense	(78)	(68)	(252)	(220)
Net income	$ 283	$ 258	$ 938	$ 838
Basic earnings per share
Basic earnings per share (in usd per share)	$ 1.04	$ 0.95	$ 3.46	$ 3.09
Diluted earnings per share
Diluted earnings per share (in usd per share)	$ 1.04	$ 0.95	$ 3.44	$ 3.08
Weighted Average Outstanding Common Stock and Common Stock Equivalents
Basic (in shares)	271.3	271.2	271.5	271.2
Diluted (in shares)	272.7	272.3	272.7	272.2

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Operations (Unaudited) - (Parenthetical) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Income Statement [Abstract]
Insurance claims and policyholders benefits, including policyholders' dividends, remeasurement impact	$ (48)	$ (41)	$ (88)	$ (75)

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Comprehensive Income (Loss) (Unaudited) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Net income	$ 283	$ 258	$ 938	$ 838
Other Comprehensive Income (Loss), net of tax
Net unrealized gains and losses on investments	1,262	(1,085)	803	(837)
Impact of changes in discount rates used to measure long-duration contract liabilities	(623)	818	(9)	678
Foreign currency translation adjustment	63	(55)	21	(4)
Pension and postretirement benefits	8	6	20	20
Other comprehensive income (loss), net of tax	710	(316)	835	(143)
Total comprehensive income (loss)	993	(58)	1,773	695
Net unrealized gains and losses on investments with an allowance for credit losses
Other Comprehensive Income (Loss), net of tax
Net unrealized gains and losses on investments	(3)	(1)	(1)	(10)
Net unrealized gains and losses on other investments
Other Comprehensive Income (Loss), net of tax
Net unrealized gains and losses on investments	$ 1,265	$ (1,084)	$ 804	$ (827)

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023
Investments:
Fixed maturity securities at fair value (amortized cost of $43,551 and $42,414, less allowance for credit loss of $18 and $16)	$ 42,579	$ 40,425
Equity securities at fair value (cost of $639 and $686)	668	683
Limited partnership investments	2,462	2,174
Other invested assets	83	80
Mortgage loans (less allowance for credit loss of $35 and $35)	1,003	1,035
Short-term investments	1,900	2,165
Total investments	48,695	46,562
Cash	456	345
Reinsurance receivables (less allowance for uncollectible receivables of $22 and $22)	5,798	5,412
Insurance receivables (less allowance for uncollectible receivables of $25 and $28)	3,489	3,442
Accrued investment income	460	444
Deferred acquisition costs	943	896
Deferred income taxes	755	1,016
Property and equipment at cost (less accumulated depreciation of $315 and $296)	258	253
Goodwill	147	146
Deferred non-insurance warranty acquisition expense	3,571	3,661
Other assets (includes $5 and $23 due from Loews Corporation)	2,784	2,534
Total assets	67,356	64,711
Insurance reserves:
Claim and claim adjustment expenses	24,558	23,304
Unearned premiums	7,259	6,933
Future policy benefits	14,047	13,959
Short-term debt	0	550
Long-term debt	2,972	2,481
Deferred non-insurance warranty revenue	4,594	4,694
Other liabilities (includes $23 and $28 due to Loews Corporation)	3,168	2,897
Total liabilities	56,598	54,818
Commitments and contingencies (Notes C and G)
Stockholders' Equity
Common stock ($2.50 par value; 500,000,000 shares authorized; 273,040,243 shares issued; 270,842,416 and 270,881,457 shares outstanding)	683	683
Additional paid-in capital	2,221	2,221
Retained earnings	9,785	9,755
Accumulated other comprehensive loss	(1,837)	(2,672)
Treasury stock (2,197,827 and 2,158,786 shares), at cost	(94)	(94)
Total stockholders’ equity	10,758	9,893
Total liabilities and stockholders' equity	$ 67,356	$ 64,711

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets - (Parenthetical) - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023
Fixed maturities securities at amortized cost	$ 43,551	$ 42,414
Marketable securities fixed maturities allowance for credit loss	18	16
Equity securities at cost	639	686
Mortgage loans on real estate commercial and consumer allowance for credit loss	35	35
Allowance for uncollectible reinsurance	22	22
Allowance for uncollectible insurance receivables	25	28
Accumulated depreciation on property and equipment	315	296
Other assets (includes $5 and $23 due from Loews Corporation)	2,784	2,534
Other liabilities (includes $23 and $28 due to Loews Corporation)	$ 3,168	$ 2,897
Common stock, par value (in usd per share)	$ 2.50	$ 2.50
Common stock, shares authorized (in shares)	500,000,000	500,000,000
Common stock, shares issued (in shares)	273,040,243	273,040,243
Common stock, shares outstanding (in shares)	270,842,416	270,881,457
Treasury stock, shares (in shares)	2,197,827	2,158,786
Related Party
Other assets (includes $5 and $23 due from Loews Corporation)	$ 5	$ 23
Other liabilities (includes $23 and $28 due to Loews Corporation)	$ 23	$ 28

Condensed Consolidated Statem_4

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023
Cash Flows from Operating Activities
Net income	$ 938	$ 838
Adjustments to reconcile net income to net cash flows provided by operating activities:
Deferred income tax expense	42	12
Trading portfolio activity	(1)	(1)
Net investment losses	42	105
Equity method investees	(93)	37
Net amortization of investments	(153)	(140)
Depreciation and amortization	51	44
Changes in:
Receivables, net	(404)	(84)
Accrued investment income	(15)	(39)
Deferred acquisition costs	(45)	(74)
Insurance reserves	1,559	1,184
Other, net	(53)	(117)
Net cash flows provided by operating activities	1,868	1,765
Dispositions:
Fixed maturity securities - sales	2,335	3,284
Fixed maturity securities - maturities, calls and redemptions	1,755	960
Equity securities	388	192
Limited partnerships	45	138
Mortgage loans	75	110
Purchases:
Fixed maturity securities	(5,016)	(5,459)
Equity securities	(332)	(200)
Limited partnerships	(235)	(322)
Mortgage loans	(43)	(75)
Change in other investments	(2)	6
Change in short-term investments	329	(99)
Purchases of property and equipment	(57)	(67)
Other, net	(4)	(5)
Net cash flows used by investing activities	(762)	(1,537)
Cash Flows from Financing Activities
Dividends paid to common stockholders	(906)	(673)
Proceeds from the issuance of debt	490	491
Repayment of debt	(550)	0
Purchase of treasury stock	(20)	(24)
Other, net	(12)	(12)
Net cash flows used by financing activities	(998)	(218)
Effect of foreign exchange rate changes on cash	3	0
Net change in cash	111	10
Cash, beginning of year	345	475
Cash, end of period	$ 456	$ 485

Condensed Consolidated Statem_5

Condensed Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($) $ in Millions	Total	Common Stock	Additional Paid-in Capital	Retained Earnings	Retained Earnings Previously Reported	Retained Earnings Revision of Prior Period, Accounting Standards Update, Adjustment	Accumulated Other Comprehensive Loss	Accumulated Other Comprehensive Loss Previously Reported	Accumulated Other Comprehensive Loss Revision of Prior Period, Accounting Standards Update, Adjustment	Treasury Stock
Total stockholder's equity at beginning of period at Dec. 31, 2022		$ 683	$ 2,220	$ 9,336	$ 9,572	$ (236)	$ (3,598)	$ (3,557)	$ (41)	$ (93)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation			(7)							22
Dividends to common stockholders ($0.44, $0.42, $3.32 and $2.46 per share)				(671)
Net income	$ 838			838
Other comprehensive income (loss)	(143)						(143)
Purchase of treasury stock	(24)									(24)
Total stockholder's equity at end of period at Sep. 30, 2023	8,563	683	2,213	9,503			(3,741)			(95)
Total stockholder's equity at beginning of period at Jun. 30, 2023		683	2,204	9,359	9,359		(3,425)	(3,425)	0	(95)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation			9							0
Dividends to common stockholders ($0.44, $0.42, $3.32 and $2.46 per share)				(114)
Net income	258			258
Other comprehensive income (loss)	(316)						(316)
Purchase of treasury stock										0
Total stockholder's equity at end of period at Sep. 30, 2023	8,563	683	2,213	9,503			(3,741)			(95)
Total stockholder's equity at beginning of period at Dec. 31, 2023	9,893	683	2,221	9,755	9,755	0	(2,672)	(2,672)	0	(94)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation			0							20
Dividends to common stockholders ($0.44, $0.42, $3.32 and $2.46 per share)				(908)
Net income	938			938
Other comprehensive income (loss)	835						835
Purchase of treasury stock	(20)									(20)
Total stockholder's equity at end of period at Sep. 30, 2024	10,758	683	2,221	9,785			(1,837)			(94)
Total stockholder's equity at beginning of period at Jun. 30, 2024		683	2,210	9,623	$ 9,623	$ 0	(2,547)	$ (2,547)	$ 0	(95)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation			11							1
Dividends to common stockholders ($0.44, $0.42, $3.32 and $2.46 per share)				(121)
Net income	283			283
Other comprehensive income (loss)	710						710
Purchase of treasury stock										0
Total stockholder's equity at end of period at Sep. 30, 2024	$ 10,758	$ 683	$ 2,221	$ 9,785			$ (1,837)			$ (94)

Condensed Consolidated Statem_6

Condensed Consolidated Statements of Stockholders' Equity (Unaudited) - (Parenthetical) - $ / shares	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Statement of Stockholders' Equity [Abstract]
Dividends declared per share (usd per share)	$ 0.44	$ 0.42	$ 3.32	$ 2.46

General

General	9 Months Ended
	Sep. 30, 2024
Accounting Policies [Abstract]
General	General Basis of Presentation The Condensed Consolidated Financial Statements include the accounts of CNA Financial Corporation (CNAF) and its subsidiaries. Collectively, CNAF and its subsidiaries are referred to as CNA or the Company. Loews Corporation (Loews) owned approximately 92% of the outstanding common stock of CNAF as of September 30, 2024. The accompanying Condensed Consolidated Financial Statements have been prepared in conformity with accounting principles generally accepted in the United States of America (GAAP). Intercompany amounts have been eliminated. Certain financial information that is normally included in annual financial statements prepared in accordance with GAAP, including certain financial statement notes, is not required for interim reporting purposes and has been condensed or omitted. These statements should be read in conjunction with the Consolidated Financial Statements and notes thereto included in CNAF's Annual Report on Form 10-K filed with the Securities and Exchange Commission (SEC) for the year ended December 31, 2023, including the summary of significant accounting policies in Note A. The preparation of Condensed Consolidated Financial Statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the Condensed Consolidated Financial Statements and the reported amounts of revenues and expenses during the reporting period. Actual results may differ from those estimates. The interim financial data as of September 30, 2024 and for the three and nine months ended September 30, 2024 and 2023 is unaudited. However, in the opinion of management, the interim data includes all adjustments, including normal recurring adjustments, necessary for a fair statement of the Company's results for the interim periods in accordance with GAAP. The results of operations for the interim periods are not necessarily indicative of the results to be expected for the full year. Accounting Standards Pending Adoption In November 2023, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) No. 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures . The updated accounting guidance requires expanded reportable segment disclosures, primarily related to significant segment expenses which are regularly provided to the Company’s Chief Operating Decision Maker (CODM). The guidance is effective for fiscal years beginning after December 15, 2023, and interim periods within annual periods beginning after December 15, 2024. Retrospective application is required. The Company is currently evaluating the effect the updated guidance will have on its financial statement disclosures and expects to disclose additional quantitative and qualitative information related to segment expenses regularly provided to the CODM that are included in the Company's measure of segment profit or loss, which is core income (loss). In December 2023, the FASB issued ASU No. 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures . The updated accounting guidance requires expanded income tax disclosures, including the disaggregation of existing disclosures related to the tax rate reconciliation and income taxes paid. The guidance is effective for annual periods beginning after December 15, 2024. Prospective application is required, with retrospective application permitted. The Company is currently evaluating the effect the updated guidance will have on the Company's financial statement disclosures.

Earnings (Loss) Per Share Data

Earnings (Loss) Per Share Data	9 Months Ended
	Sep. 30, 2024
Earnings Per Share [Abstract]
Earnings (Loss) Per Share Data	Earnings (Loss) Per Share Data Earnings (loss) per share is based on weighted average number of outstanding common shares. Basic earnings (loss) per share excludes the impact of dilutive securities and is computed by dividing Net income (loss) by the weighted average number of common shares outstanding for the period. Diluted earnings (loss) per share reflects the potential dilution that could occur if securities or other contracts to issue common stock were exercised or converted into common stock. The following table presents the income and share data used in the basic and diluted earnings per share computations. Periods ended September 30 Three Months Nine Months (In millions, except per share data) 2024 2023 2024 2023 Net income (loss) $ 283 $ 258 $ 938 $ 838 Common Stock and Common Stock Equivalents Basic Weighted average shares outstanding 271.3 271.2 271.5 271.2 Diluted Weighted average shares outstanding 271.3 271.2 271.5 271.2 Dilutive effect of stock-based awards under compensation plans 1.4 1.1 1.2 1.0 Total 272.7 272.3 272.7 272.2 Earnings (loss) per share Basic $ 1.04 $ 0.95 $ 3.46 $ 3.09 Diluted $ 1.04 $ 0.95 $ 3.44 $ 3.08 Excluded from the calculation of diluted earnings (loss) per share is the impact of potential shares attributable to exercises or conversions into common stock under stock-based employee compensation plans that would have been antidilutive during the respective periods.

Investments

Investments	9 Months Ended
	Sep. 30, 2024
Investments [Abstract]
Investments	Investments The significant components of Net investment income are presented in the following table. Periods ended September 30 Three Months Nine Months (In millions) 2024 2023 2024 2023 Fixed maturity securities $ 517 $ 491 $ 1,530 $ 1,443 Equity securities 21 9 56 42 Limited partnership investments 67 28 195 108 Mortgage loans 14 15 43 43 Short-term investments 20 23 68 51 Trading portfolio — 1 1 4 Other 8 6 23 20 Gross investment income 647 573 1,916 1,711 Investment expense (21) (20) (63) (58) Net investment income $ 626 $ 553 $ 1,853 $ 1,653 Net investment income (loss) recognized due to the change in fair value of common stock held as of September 30, 2024 and 2023 $ 11 $ (3) $ 20 $ 2 Net investment gains (losses) are presented in the following table. Periods ended September 30 Three Months Nine Months (In millions) 2024 2023 2024 2023 Net investment gains (losses): Fixed maturity securities: Gross gains $ 11 $ 12 $ 38 $ 55 Gross losses (33) (49) (104) (141) Net investment gains (losses) on fixed maturity securities (22) (37) (66) (86) Equity securities 13 2 25 (9) Mortgage loans — (5) — (11) Short-term investments and other (1) 2 (1) 1 Net investment gains (losses) $ (10) $ (38) $ (42) $ (105) Net investment gains (losses) recognized due to the change in fair value of non-redeemable preferred stock held as of September 30, 2024 and 2023 $ 13 $ 2 $ 24 $ 2 The available-for-sale impairment losses (gains) recognized in earnings by asset type are presented in the following table. The table includes losses (gains) on securities with an intention to sell and changes in the allowance for credit losses on securities since acquisition date. Periods ended September 30 Three Months Nine Months (In millions) 2024 2023 2024 2023 Fixed maturity securities available-for-sale: Corporate and other bonds $ 8 $ 8 $ 23 $ 25 Asset-backed 4 4 9 12 Impairment losses (gains) recognized in earnings $ 12 $ 12 $ 32 $ 37 There were no losses recognized on mortgage loans during the three and nine months ended September 30, 2024. There were $5 million and $11 million of losses recognized on mortgage loans during the three and nine months ended September 30, 2023. The following tables present a summary of fixed maturity securities. September 30, 2024 Cost or Gross Gross Allowance for Credit Losses Estimated (In millions) Fixed maturity securities available-for-sale: Corporate and other bonds $ 25,872 $ 826 $ 900 $ 6 $ 25,792 States, municipalities and political subdivisions 7,406 359 617 — 7,148 Asset-backed: Residential mortgage-backed 3,684 32 362 — 3,354 Commercial mortgage-backed 1,867 15 141 — 1,741 Other asset-backed 3,743 40 186 12 3,585 Total asset-backed 9,294 87 689 12 8,680 U.S. Treasury and obligations of government-sponsored enterprises 224 2 4 — 222 Foreign government 755 8 26 — 737 Total fixed maturity securities available-for-sale 43,551 1,282 2,236 18 42,579 Total fixed maturity securities trading — — — — — Total fixed maturity securities $ 43,551 $ 1,282 $ 2,236 $ 18 $ 42,579 December 31, 2023 Cost or Gross Gross Allowance for Credit Losses Estimated (In millions) Fixed maturity securities available-for-sale: Corporate and other bonds $ 25,020 $ 597 $ 1,345 $ 4 $ 24,268 States, municipalities and political subdivisions 7,713 382 703 — 7,392 Asset-backed: Residential mortgage-backed 3,411 16 425 — 3,002 Commercial mortgage-backed 1,862 7 230 8 1,631 Other asset-backed 3,515 13 256 4 3,268 Total asset-backed 8,788 36 911 12 7,901 U.S. Treasury and obligations of government-sponsored enterprises 152 1 2 — 151 Foreign government 741 6 34 — 713 Total fixed maturity securities available-for-sale 42,414 1,022 2,995 16 40,425 Total fixed maturity securities trading — — — — — Total fixed maturity securities $ 42,414 $ 1,022 $ 2,995 $ 16 $ 40,425 The following tables present the estimated fair value and gross unrealized losses of available-for-sale fixed maturity securities in a gross unrealized loss position for which an allowance for credit loss has not been recorded, by the length of time in which the securities have continuously been in that position. Less than 12 Months 12 Months or Longer Total September 30, 2024 Estimated Gross Estimated Gross Estimated Gross (In millions) Fixed maturity securities available-for-sale: Corporate and other bonds $ 1,664 $ 31 $ 11,240 $ 869 $ 12,904 $ 900 States, municipalities and political subdivisions 422 7 3,155 610 3,577 617 Asset-backed: Residential mortgage-backed 130 2 2,162 360 2,292 362 Commercial mortgage-backed 112 — 1,134 141 1,246 141 Other asset-backed 151 4 1,638 182 1,789 186 Total asset-backed 393 6 4,934 683 5,327 689 U.S. Treasury and obligations of government-sponsored enterprises 45 2 45 2 90 4 Foreign government 99 1 403 25 502 26 Total $ 2,623 $ 47 $ 19,777 $ 2,189 $ 22,400 $ 2,236 Less than 12 Months 12 Months or Longer Total December 31, 2023 Estimated Gross Estimated Gross Estimated Gross (In millions) Fixed maturity securities available-for-sale: Corporate and other bonds $ 1,943 $ 37 $ 13,406 $ 1,308 $ 15,349 $ 1,345 States, municipalities and political subdivisions 598 18 3,104 685 3,702 703 Asset-backed: Residential mortgage-backed 233 4 2,212 421 2,445 425 Commercial mortgage-backed 200 5 1,184 225 1,384 230 Other asset-backed 392 8 1,869 248 2,261 256 Total asset-backed 825 17 5,265 894 6,090 911 U.S. Treasury and obligations of government-sponsored enterprises 65 1 23 1 88 2 Foreign government 52 1 450 33 502 34 Total $ 3,483 $ 74 $ 22,248 $ 2,921 $ 25,731 $ 2,995 The following table presents the estimated fair value and gross unrealized losses of available-for-sale fixed maturity securities in a gross unrealized loss position for which an allowance for credit loss has not been recorded, by ratings distribution. September 30, 2024 December 31, 2023 (In millions) Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses U.S. Government, Government agencies and Government-sponsored enterprises $ 2,127 $ 265 $ 2,273 $ 309 AAA 1,277 221 1,524 261 AA 3,641 547 3,817 658 A 5,229 405 5,652 517 BBB 9,243 689 11,523 1,095 Non-investment grade 883 109 942 155 Total $ 22,400 $ 2,236 $ 25,731 $ 2,995 Based on current facts and circumstances, the Company believes the unrealized losses presented in the September 30, 2024 securities in a gross unrealized loss position tables above are not indicative of the ultimate collectability of the current amortized cost of the securities, but rather are primarily attributable to changes in risk-free interest rates. In reaching this determination, the Company considered the volatility in risk-free rates and credit spreads as well as the fact that its unrealized losses are concentrated in investment grade issuers. Additionally, the Company has no current intent to sell securities with unrealized losses, nor is it more likely than not that it will be required to sell prior to recovery of amortized cost; accordingly, the Company has determined that there are no additional impairment losses to be recorded as of September 30, 2024. The following tables present the activity related to the allowance on available-for-sale securities with credit impairments and purchased credit-deteriorated (PCD) assets. Accrued interest receivable on available-for-sale fixed maturity securities totaled $451 million, $435 million, and $430 million as of September 30, 2024, December 31, 2023, and September 30, 2023 and is excluded from the estimate of expected credit losses and the amortized cost basis in the tables included within this Note. (In millions) Corporate and other bonds Asset-backed Total Allowance for credit losses: Balance as of July 1, 2024 $ — $ 17 $ 17 Additions to the allowance for credit losses: Securities for which credit losses were not previously recorded 4 — 4 Available-for-sale securities accounted for as PCD assets 2 — 2 Reductions to the allowance for credit losses: Securities sold during the period (realized) — — — Intent to sell or more likely than not will be required to sell the security before recovery of its amortized cost basis — — — Write-offs charged against the allowance — 9 9 Recoveries of amounts previously written off — — — Additional increases or (decreases) to the allowance for credit losses on securities that had an allowance recorded in a previous period — 4 4 Balance as of September 30, 2024 $ 6 $ 12 $ 18 (In millions) Corporate and other bonds Asset-backed Total Allowance for credit losses: Balance as of July 1, 2023 $ 13 $ 9 $ 22 Additions to the allowance for credit losses: Securities for which credit losses were not previously recorded 5 — 5 Available-for-sale securities accounted for as PCD assets 2 — 2 Reductions to the allowance for credit losses: Securities sold during the period (realized) — — — Intent to sell or more likely than not will be required to sell the security before recovery of its amortized cost basis — — — Write-offs charged against the allowance 15 — 15 Recoveries of amounts previously written off — — — Additional increases or (decreases) to the allowance for credit losses on securities that had an allowance recorded in a previous period — 4 4 Balance as of September 30, 2023 $ 5 $ 13 $ 18 (In millions) Corporate and other bonds Asset-backed Total Allowance for credit losses: Balance as of January 1, 2024 $ 4 $ 12 $ 16 Additions to the allowance for credit losses: Securities for which credit losses were not previously recorded 4 — 4 Available-for-sale securities accounted for as PCD assets 2 — 2 Reductions to the allowance for credit losses: Securities sold during the period (realized) 3 1 4 Intent to sell or more likely than not will be required to sell the security before recovery of its amortized cost basis 1 — 1 Write-offs charged against the allowance — 9 9 Recoveries of amounts previously written off — — — Additional increases or (decreases) to the allowance for credit losses on securities that had an allowance recorded in a previous period — 10 10 Balance as of September 30, 2024 $ 6 $ 12 $ 18 (In millions) Corporate and other bonds Asset-backed Total Allowance for credit losses: Balance as of January 1, 2023 $ — $ 1 $ 1 Additions to the allowance for credit losses: Securities for which credit losses were not previously recorded 6 7 13 Available-for-sale securities accounted for as PCD assets 22 — 22 Reductions to the allowance for credit losses: Securities sold during the period (realized) 6 — 6 Intent to sell or more likely than not will be required to sell the security before recovery of its amortized cost basis 3 — 3 Write-offs charged against the allowance 15 — 15 Recoveries of amounts previously written off — — — Additional increases or (decreases) to the allowance for credit losses on securities that had an allowance recorded in a previous period 1 5 6 Balance as of September 30, 2023 $ 5 $ 13 $ 18 Contractual Maturity The following table presents available-for-sale fixed maturity securities by contractual maturity. September 30, 2024 December 31, 2023 (In millions) Cost or Estimated Cost or Estimated Due in one year or less $ 1,585 $ 1,565 $ 1,121 $ 1,091 Due after one year through five years 11,948 11,800 11,563 11,180 Due after five years through ten years 13,333 12,959 13,359 12,573 Due after ten years 16,685 16,255 16,371 15,581 Total $ 43,551 $ 42,579 $ 42,414 $ 40,425 Actual maturities may differ from contractual maturities because certain securities may be called or prepaid. Securities not due at a single date are allocated based on weighted average life. Investment Commitments As part of its overall investment strategy, the Company invests in various assets which require future purchase, sale or funding commitments. These investments are recorded once funded, and the related commitments may include future capital calls from various third-party limited partnerships, signed and accepted mortgage loan applications, and obligations related to private placement securities. As of September 30, 2024, the Company had commitments to purchase or fund approximately $1,645 million and sell approximately $90 million under the terms of these investments. Related Party Investment During the three months ended September 30, 2024, the Company invested in a commercial mortgage-backed securitization whose underlying mortgage loan is an obligation of an affiliate of Loews that matures in September of 2034. The Company purchased $50 million of par at issuance across three separate investment grade tranches of the $305 million securitization. The Company's position in this commercial mortgage-backed securitization is included in the Fixed maturity securities at fair value line on the Condensed Consolidated Balance Sheets and was $52 million as of September 30, 2024. The Company recognized less than $1 million of income in Net investment income related to this investment during the three months ended September 30, 2024. Mortgage Loans The following table presents the amortized cost basis of mortgage loans for each credit quality indicator by year of origination. The primary credit quality indicators utilized are debt service coverage ratios (DSCR) and loan-to-value ratios (LTV). September 30, 2024 Mortgage Loans Amortized Cost Basis by Origination Year (1) (In millions) 2024 2023 2022 2021 2020 Prior Total DSCR ≥1.6x LTV less than 55% $ — $ 33 $ 9 $ 2 $ 97 $ 242 $ 383 LTV 55% to 65% — — — 5 — — 5 LTV greater than 65% — — 30 12 — — 42 DSCR 1.2x - 1.6x LTV less than 55% — 28 5 — 13 50 96 LTV 55% to 65% 43 20 36 36 4 31 170 LTV greater than 65% — 13 64 — 20 — 97 DSCR ≤1.2 LTV less than 55% — — — — — — — LTV 55% to 65% — 32 75 — — 41 148 LTV greater than 65% — — 28 21 — 48 97 Total $ 43 $ 126 $ 247 $ 76 $ 134 $ 412 $ 1,038 (1) The values in the table above reflect DSCR on a standardized amortization period and LTV based on the most recent appraised values trended forward using changes in a commercial real estate price index. As of September 30, 2024, accrued interest receivable on mortgage loans totaled $4 million and is excluded from the amortized cost basis disclosed in the table above and the estimate of expected credit losses.

Fair Value

Fair Value	9 Months Ended
	Sep. 30, 2024
Fair Value Disclosures [Abstract]
Fair Value	Fair Value Fair value is the price that would be received upon sale of an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. The following fair value hierarchy is used in selecting inputs, with the highest priority given to Level 1, as these are the most transparent or reliable. Level 1 - Quoted prices for identical instruments in active markets. Level 2 - Quoted prices for similar instruments in active markets; quoted prices for identical or similar instruments in markets that are not active; and model-derived valuations in which all significant inputs are observable in active markets. Level 3 - Valuations derived from valuation techniques in which one or more significant inputs are not observable. Prices may fall within Level 1, 2 or 3 depending upon the methodology and inputs used to estimate fair value for each specific security. In general, the Company seeks to price securities using third-party pricing services. Securities not priced by pricing services are submitted to independent brokers for valuation and, if those are not available, internally developed pricing models are used to value assets using a methodology and inputs the Company believes market participants would use to value the assets. Prices obtained from third-party pricing services or brokers are not adjusted by the Company. The Company performs control procedures over information obtained from pricing services and brokers to ensure prices received represent a reasonable estimate of fair value and to confirm representations regarding whether inputs are observable or unobservable. Procedures may include i) the review of pricing service methodologies or broker pricing qualifications, ii) back-testing, where past fair value estimates are compared to actual transactions executed in the market on similar dates, iii) exception reporting, where period-over-period changes in price are reviewed and challenged with the pricing service or broker based on exception criteria, and iv) deep dives, where the Company performs an independent analysis of the inputs and assumptions used to price individual securities. Assets and Liabilities Measured at Fair Value Assets and liabilities measured at fair value on a recurring basis are presented in the following tables. Corporate bonds and other includes obligations of the United States of America (U.S.) Treasury, government-sponsored enterprises, foreign governments and redeemable preferred stock. September 30, 2024 Total (In millions) Level 1 Level 2 Level 3 Assets Fixed maturity securities: Corporate bonds and other $ 225 $ 25,289 $ 1,237 $ 26,751 States, municipalities and political subdivisions — 7,103 45 7,148 Asset-backed — 7,765 915 8,680 Total fixed maturity securities 225 40,157 2,197 42,579 Equity securities: Common stock 171 — 12 183 Non-redeemable preferred stock 47 436 2 485 Total equity securities 218 436 14 668 Short-term and other 1,691 30 — 1,721 Total assets $ 2,134 $ 40,623 $ 2,211 $ 44,968 Liabilities Other liabilities $ — $ — $ — $ — Total liabilities $ — $ — $ — $ — December 31, 2023 Total (In millions) Level 1 Level 2 Level 3 Assets Fixed maturity securities: Corporate bonds and other $ 161 $ 23,926 $ 1,045 $ 25,132 States, municipalities and political subdivisions — 7,348 44 7,392 Asset-backed — 7,000 901 7,901 Total fixed maturity securities 161 38,274 1,990 40,425 Equity securities: Common stock 167 — 24 191 Non-redeemable preferred stock 52 440 — 492 Total equity securities 219 440 24 683 Short-term and other 1,976 32 — 2,008 Total assets $ 2,356 $ 38,746 $ 2,014 $ 43,116 Liabilities Other liabilities $ — $ 1 $ — $ 1 Total liabilities $ — $ 1 $ — $ 1 The tables below present a reconciliation for all assets and liabilities measured at fair value on a recurring basis using significant unobservable inputs (Level 3). Level 3 (In millions) Corporate bonds and other States, municipalities and political subdivisions Asset-backed Equity securities Total Balance as of July 1, 2024 $ 1,129 $ 43 $ 887 $ 14 $ 2,073 Total realized and unrealized investment gains (losses): Reported in Net investment gains (losses) — — (3) — (3) Reported in Net investment income — — 4 — 4 Reported in Other comprehensive income (loss) 59 2 30 — 91 Total realized and unrealized investment gains (losses) 59 2 31 — 92 Purchases 83 — 38 — 121 Sales (10) — — — (10) Settlements (24) — (23) — (47) Transfers into Level 3 — — — — — Transfers out of Level 3 — — (18) — (18) Balance as of September 30, 2024 $ 1,237 $ 45 $ 915 $ 14 $ 2,211 Unrealized gains (losses) on Level 3 assets and liabilities held as of September 30, 2024 recognized in Net income (loss) in the period $ — $ — $ — $ — $ — Unrealized gains (losses) on Level 3 assets and liabilities held as of September 30, 2024 recognized in Other comprehensive income (loss) in the period 57 2 30 — 89 Level 3 (In millions) Corporate bonds and other States, municipalities and political subdivisions Asset-backed Equity securities Total Balance as of July 1, 2023 $ 971 $ 43 $ 883 $ 26 $ 1,923 Total realized and unrealized investment gains (losses): Reported in Net investment gains (losses) — — (4) — (4) Reported in Net investment income — — 5 (1) 4 Reported in Other comprehensive income (loss) (36) (2) (28) — (66) Total realized and unrealized investment gains (losses) (36) (2) (27) (1) (66) Purchases 29 — 61 — 90 Sales — — — (2) (2) Settlements (19) — (13) — (32) Transfers into Level 3 — — — — — Transfers out of Level 3 — — (7) — (7) Balance as of September 30, 2023 $ 945 $ 41 $ 897 $ 23 $ 1,906 Unrealized gains (losses) on Level 3 assets and liabilities held as of September 30, 2023 recognized in Net income (loss) in the period $ — $ — $ — $ (1) $ (1) Unrealized gains (losses) on Level 3 assets and liabilities held as of September 30, 2023 recognized in Other comprehensive income (loss) in the period (36) (2) (28) — (66) Level 3 (In millions) Corporate bonds and other States, municipalities and political subdivisions Asset-backed Equity securities Total Balance as of January 1, 2024 $ 1,045 $ 44 $ 901 $ 24 $ 2,014 Total realized and unrealized investment gains (losses): Reported in Net investment gains (losses) — — (10) — (10) Reported in Net investment income — — 15 6 21 Reported in Other comprehensive income (loss) 39 1 14 — 54 Total realized and unrealized investment gains (losses) 39 1 19 6 65 Purchases 229 — 111 3 343 Sales (10) — (14) (19) (43) Settlements (77) — (65) — (142) Transfers into Level 3 11 — — — 11 Transfers out of Level 3 — — (37) — (37) Balance as of September 30, 2024 $ 1,237 $ 45 $ 915 $ 14 $ 2,211 Unrealized gains (losses) on Level 3 assets and liabilities held as of September 30, 2024 recognized in Net income (loss) in the period $ — $ — $ — $ 2 $ 2 Unrealized gains (losses) on Level 3 assets and liabilities held as of September 30, 2024 recognized in Other comprehensive income (loss) in the period 34 1 14 — 49 Level 3 (In millions) Corporate bonds and other States, municipalities and political subdivisions Asset-backed Equity securities Total Balance as of January 1, 2023 $ 810 $ 43 $ 788 $ 35 $ 1,676 Total realized and unrealized investment gains (losses): Reported in Net investment gains (losses) — — (5) — (5) Reported in Net investment income — — 15 (8) 7 Reported in Other comprehensive income (loss) (27) (2) (28) — (57) Total realized and unrealized investment gains (losses) (27) (2) (18) (8) (55) Purchases 178 — 203 — 381 Sales — — — (4) (4) Settlements (27) — (39) — (66) Transfers into Level 3 11 — 23 — 34 Transfers out of Level 3 — — (60) — (60) Balance as of September 30, 2023 $ 945 $ 41 $ 897 $ 23 $ 1,906 Unrealized gains (losses) on Level 3 assets and liabilities held as of September 30, 2023 recognized in Net income (loss) in the period $ — $ — $ — $ (8) $ (8) Unrealized gains (losses) on Level 3 assets and liabilities held as of September 30, 2023 recognized in Other comprehensive income (loss) in the period (27) (2) (28) — (57) Valuation Methodologies and Inputs The following section describes the valuation methodologies and relevant inputs used to measure different financial instruments at fair value, including an indication of the level in the fair value hierarchy in which the instruments are generally classified. Fixed Maturity Securities Level 1 securities include highly liquid government securities and exchange traded bonds, valued using quoted market prices. Level 2 securities include most other fixed maturity securities as the significant inputs are observable in the marketplace. All classes of Level 2 fixed maturity securities are valued using a methodology based on information generated by market transactions involving identical or comparable assets, a discounted cash flow methodology, or a combination of both when necessary. Common inputs for all classes of fixed maturity securities include prices from recently executed transactions of similar securities, marketplace quotes, benchmark yields, spreads off benchmark yields, interest rates and U.S. Treasury or swap curves. Specifically for asset-backed securities, key inputs include prepayment and default projections based on past performance of the underlying collateral and current market data. Fixed maturity securities are primarily assigned to Level 3 in cases where broker/dealer quotes are significant inputs to the valuation and there is a lack of transparency as to whether these quotes are based on information that is observable in the marketplace. Level 3 securities also include private placement debt securities whose fair value is determined using internal models with some inputs that are not market observable. Equity Securities Level 1 equity securities include publicly traded securities valued using quoted market prices. Level 2 securities are primarily valued using pricing for similar securities, recently executed transactions and other pricing models utilizing market observable inputs. Level 3 securities are primarily priced using broker/dealer quotes and internal models with some inputs that are not market observable. Short-Term and Other Invested Assets Securities that are actively traded or have quoted prices are classified as Level 1. These securities include money market funds and treasury bills. Level 2 primarily includes non-U.S. government securities for which all inputs are market observable. Fixed maturity securities purchased within one year of maturity are classified consistent with fixed maturity securities discussed above. Short-term investments as presented in the tables above differ from the amounts presented on the Condensed Consolidated Balance Sheets because certain short-term investments, such as time deposits, are not measured at fair value. As of September 30, 2024 and December 31, 2023, there were $77 million and $75 million of overseas deposits within Other invested assets, which can be redeemed at net asset value in 90 days or less. Overseas deposits are excluded from the fair value hierarchy because their fair value is recorded using the net asset value per share (or equivalent) practical expedient. Other Liabilities Level 2 securities include currency forward contracts valued using observable market forward rates. Significant Unobservable Inputs The following tables present quantitative information about the significant unobservable inputs utilized by the Company in the fair value measurements of Level 3 assets. Valuations for assets and liabilities not presented in the tables below are primarily based on broker/dealer quotes for which there is a lack of transparency as to inputs used to develop the valuations. The quantitative detail of these unobservable inputs is neither provided nor reasonably available to the Company. The weighted average rate is calculated based on fair value. September 30, 2024 Estimated Fair Value Valuation Technique(s) Unobservable Input(s) Range Fixed maturity securities $ 1,713 Discounted cash flow Credit spread 1% - 6% (2%) December 31, 2023 Estimated Fair Value Valuation Technique(s) Unobservable Input(s) Range Fixed maturity securities $ 1,495 Discounted cash flow Credit spread 1% - 7% (2%) For fixed maturity securities, an increase to the credit spread assumptions would result in a lower fair value measurement. Financial Assets and Liabilities Not Measured at Fair Value The carrying amount and estimated fair value of the Company's financial assets and liabilities which are not measured at fair value on the Condensed Consolidated Balance Sheets are presented in the following tables. September 30, 2024 Carrying Estimated Fair Value (In millions) Level 1 Level 2 Level 3 Total Assets Mortgage loans $ 1,003 $ — $ — $ 988 $ 988 Liabilities Short-term debt $ — $ — $ — $ — $ — Long-term debt 2,972 — 2,952 — 2,952 December 31, 2023 Carrying Estimated Fair Value (In millions) Level 1 Level 2 Level 3 Total Assets Mortgage loans $ 1,035 $ — $ — $ 997 $ 997 Liabilities Short-term debt $ 550 $ — $ 546 $ — $ 546 Long-term debt 2,481 — 2,385 — 2,385 The carrying amounts reported on the Condensed Consolidated Balance Sheets for Cash, Short-term investments not carried at fair value, Accrued investment income and certain Other assets and Other liabilities approximate fair value due to the short-term nature of these items. These assets and liabilities are not listed in the tables above.

Claim and Claim Adjustment Expe

Claim and Claim Adjustment Expense Reserves	9 Months Ended
	Sep. 30, 2024
Liability for Future Policy Benefits and Unpaid Claims and Claims Adjustment Expense [Abstract]
Claim and Claim Adjustment Expense Reserves	Claim and Claim Adjustment Expense Reserves Claim and claim adjustment expense reserves represent the estimated amounts necessary to resolve all outstanding claims, including incurred but not reported (IBNR) claims as of the reporting date. The Company's reserve projections are based primarily on detailed analysis of the facts in each case, the Company's experience with similar cases and various historical development patterns. Consideration is given to historical patterns such as claim reserving trends and settlement practices, loss payments, pending levels of unpaid claims and product mix, economic, medical and social inflation, and public attitudes. All of these factors can affect the estimation of claim and claim adjustment expense reserves. Establishing claim and claim adjustment expense reserves, including claim and claim adjustment expense reserves for catastrophic events that have occurred, is an estimation process. Many factors can ultimately affect the final settlement of a claim and, therefore, the necessary reserve. Changes in the law, results of litigation, medical costs, the cost of repair materials and labor rates can affect ultimate claim costs. In addition, time can be a critical part of reserving determinations since the longer the span between the incidence of a loss and the payment or settlement of the claim, the more variable the ultimate settlement amount can be. Accordingly, short-tail claims, such as property damage claims, tend to be more reasonably estimable than long-tail claims, such as workers' compensation, general liability and professional liability claims. Claim and claim adjustment expense reserves are also maintained for the Company's structured settlement obligations. In developing the claim and claim adjustment expense reserve estimates for structured settlement obligations, the Company's actuaries review mortality experience on an annual basis. Adjustments to prior year reserve estimates, if necessary, are reflected in the results of operations in the period that the need for such adjustments is determined. There can be no assurance that the Company's ultimate cost for insurance losses will not exceed current estimates. Catastrophes are an inherent risk of the property and casualty insurance business and have contributed to material period-to-period fluctuations in our results of operations and/or equity. The Company reported catastrophe losses, net of reinsurance, of $143 million and $313 million for the three and nine months ended September 30, 2024 primarily related to severe weather related events, including $55 million for Hurricane Helene. The Company reported catastrophe losses, net of reinsurance, of $94 million and $214 million for the three and nine months ended September 30, 2023 primarily related to severe weather related events. Liability for Unpaid Claim and Claim Adjustment Expenses The following table presents a reconciliation between beginning and ending claim and claim adjustment expense reserves. For the nine months ended September 30 (In millions) 2024 2023 Reserves, beginning of year: Gross $ 23,304 $ 22,120 Ceded 5,141 5,191 Net reserves, beginning of year 18,163 16,929 Net incurred claim and claim adjustment expenses: Provision for insured events of current year 4,706 4,221 Increase (decrease) in provision for insured events of prior years 26 43 Amortization of discount 30 33 Total net incurred (1) 4,762 4,297 Net payments attributable to: Current year events (655) (588) Prior year events (3,189) (2,953) Total net payments (3,844) (3,541) Foreign currency translation adjustment and other 35 (30) Net reserves, end of period 19,116 17,655 Ceded reserves, end of period 5,442 5,181 Gross reserves, end of period $ 24,558 $ 22,836 (1) Total net incurred does not agree to Insurance claims and policyholders' benefits as reflected on the Condensed Consolidated Statements of Operations due to amounts related to retroactive reinsurance deferred gain accounting, uncollectible reinsurance, benefit expenses related to future policy benefits and policyholders' dividends, which are not reflected in the table above. Net Prior Year Development Changes in estimates of claim and claim adjustment expense reserves, net of reinsurance, for prior years are defined as net prior year loss reserve development (development). These changes can be favorable or unfavorable. The following table presents development recorded for the Specialty, Commercial, International and Corporate & Other segments. Periods ended September 30 Three Months Nine Months (In millions) 2024 2023 2024 2023 Pretax (favorable) unfavorable development: Specialty $ — $ (5) $ (8) $ (9) Commercial (3) (2) (11) (17) International (2) — (5) 15 Corporate & Other 22 20 57 55 Total pretax (favorable) unfavorable development $ 17 $ 13 $ 33 $ 44 Unfavorable development of $22 million and $57 million was recorded within the Corporate & Other segment for the three and nine months ended September 30, 2024 and unfavorable development of $20 million and $55 million was recorded for the three and nine months ended September 30, 2023, largely associated with legacy mass tort abuse claims. Specialty The following table presents further detail of the development recorded for the Specialty segment. Periods ended September 30 Three Months Nine Months (In millions) 2024 2023 2024 2023 Pretax (favorable) unfavorable development: Medical Professional Liability $ — $ — $ (2) $ 9 Other Professional Liability and Management Liability 11 17 28 16 Surety (20) (21) (46) (28) Warranty 7 (2) 20 (11) Other 2 1 (8) 5 Total pretax (favorable) unfavorable development $ — $ (5) $ (8) $ (9) Three Months 2024 Unfavorable development in other professional liability and management liability was primarily due to higher than expected large claim severity in the Company's directors and officers (D&O) business in accident year 2019. Favorable development in surety was primarily due to lower than expected frequency and lack of systemic activity in multiple accident years. 2023 Unfavorable development in other professional liability and management liability was primarily due to higher than expected claim severity and frequency in the Company’s cyber and professional errors and omissions (E&O) businesses in multiple accident years. Favorable development in surety was primarily due to lower than expected frequency and lack of systemic activity in multiple accident years. Nine Months 2024 Unfavorable development in other professional liability and management liability was primarily due to higher than expected claim severity and frequency in the Company's professional E&O and cyber businesses. Favorable development in surety was primarily due to lower than expected frequency and lack of systemic activity in multiple accident years. Unfavorable development in warranty was primarily due to higher than expected frequency and severity in a recent accident year. 2023 Unfavorable development in other professional liability and management liability was primarily due to higher than expected claim severity and frequency in the Company’s cyber and professional E&O businesses in multiple accident years. Favorable development in surety was primarily due to lower than expected frequency and lack of systemic activity in multiple accident years. Favorable development in warranty was due to lower than expected loss emergence in a recent accident year. Commercial The following table presents further detail of the development recorded for the Commercial segment. Periods ended September 30 Three Months Nine Months (In millions) 2024 2023 2024 2023 Pretax (favorable) unfavorable development: Commercial Auto $ 25 $ — $ 46 $ 11 General Liability 28 — 47 70 Workers' Compensation (57) (2) (106) (100) Property and Other 1 — 2 2 Total pretax (favorable) unfavorable development $ (3) $ (2) $ (11) $ (17) Three and Nine Months 2024 Unfavorable development in commercial auto was due to higher than expected claim severity in recent accident years. Unfavorable development in general liability was due to higher than expected large claim severity in multiple accident years going back to 2015. Favorable development in workers’ compensation was due to favorable medical trends driving lower than expected severity primarily in accident years 2018 and prior. Nine Months 2023 Unfavorable development in commercial auto was due to higher than expected claim severity in the Company’s construction business in a recent accident year. Unfavorable development in general liability was due to higher than expected claim severity in the Company’s construction and middle market businesses across multiple accident years. Favorable development in workers’ compensation was due to favorable medical trends driving lower than expected severity in multiple accident years. International The following table presents further detail of the development recorded for the International segment. Periods ended September 30 Three Months Nine Months (In millions) 2024 2023 2024 2023 Pretax (favorable) unfavorable development: Commercial $ (13) $ — $ (7) $ (5) Specialty 11 — 2 22 Other — — — (2) Total pretax (favorable) unfavorable development $ (2) $ — $ (5) $ 15 Three Months 2024 Favorable development in commercial was due to lower than expected loss emergence across multiple accident years in the Company's marine and property businesses. Unfavorable development in specialty was due to higher than expected large loss emergence across several accident years. Nine Months 2023 Unfavorable development in Specialty was due to higher than expected large loss emergence in the Company’s professional liability business in accident year 2017. Asbestos & Environmental Pollution (A&EP) Reserves In 2010, Continental Casualty Company (CCC) together with several of the Company’s insurance subsidiaries completed a transaction with National Indemnity Company (NICO), a subsidiary of Berkshire Hathaway Inc., under which substantially all of the Company’s legacy A&EP liabilities were ceded to NICO through a Loss Portfolio Transfer (LPT). At the effective date of the transaction, the Company ceded approximately $1.6 billion of net A&EP claim and allocated claim adjustment expense reserves to NICO under a retroactive reinsurance agreement with an aggregate limit of $4.0 billion. The $1.6 billion of claim and allocated claim adjustment expense reserves ceded to NICO was net of $1.2 billion of ceded claim and allocated claim adjustment expense reserves under existing third-party reinsurance contracts. The NICO LPT aggregate reinsurance limit also covers credit risk on the existing third-party reinsurance related to these liabilities. The Company paid NICO a reinsurance premium of $2.0 billion and transferred to NICO billed third-party reinsurance receivables related to A&EP claims with a net book value of $215 million, resulting in total consideration of $2.2 billion. In years subsequent to the effective date of the LPT, the Company recognized adverse prior year development on its A&EP reserves resulting in additional amounts ceded under the LPT. As a result, the cumulative amounts ceded under the LPT have exceeded the $2.2 billion consideration paid, resulting in the NICO LPT moving into a gain position, requiring retroactive reinsurance accounting. Under retroactive reinsurance accounting, this gain is deferred and only recognized in earnings in proportion to actual paid recoveries under the LPT. Over the life of the contract, there is no economic impact as long as any additional losses incurred are within the limit of the LPT. In a period in which the Company recognizes a change in the estimate of A&EP reserves that increases or decreases the amounts ceded under the LPT, the proportion of actual paid recoveries to total ceded losses is affected and the change in the deferred gain is recognized in earnings as if the revised estimate of ceded losses was available at the effective date of the LPT. The effect of the deferred retroactive reinsurance benefit is recorded in Insurance claims and policyholders' benefits in the Condensed Consolidated Statements of Operations. The impact of the LPT on the Condensed Consolidated Statements of Operations was the recognition of a retroactive reinsurance benefit of $11 million and $15 million for the three months ended September 30, 2024 and 2023 and $36 million and $38 million for the nine months ended September 30, 2024 and 2023. As of September 30, 2024 and December 31, 2023, the cumulative amounts ceded under the LPT were $3.6 billion. The unrecognized deferred retroactive reinsurance benefit was $382 million and $417 million as of September 30, 2024 and December 31, 2023 and is included within Other liabilities on the Condensed Consolidated Balance Sheets. NICO established a collateral trust account as security for its obligations to the Company. The fair value of the collateral trust account was $2.3 billion as of September 30, 2024. In addition, Berkshire Hathaway Inc. guaranteed the payment obligations of NICO up to the aggregate reinsurance limit as well as certain of NICO’s performance obligations under the trust agreement. NICO is responsible for claims handling and billing and collection from third-party reinsurers related to the majority of the Company’s A&EP claims. Credit Risk for Ceded Reserves The majority of the Company’s outstanding voluntary reinsurance receivables are due from reinsurers with financial strength ratings of A- or higher. Receivables due from reinsurers with lower financial strength ratings are primarily due from captive reinsurers and are backed by collateral arrangements.

Future Policy Benefits Reserves

Future Policy Benefits Reserves	9 Months Ended
	Sep. 30, 2024
Insurance [Abstract]
Future Policy Benefits Reserves	Future Policy Benefits Reserves Future policy benefits reserves are associated with the Company's run-off long-term care business, included in the Life & Group segment, and relate to policyholders that are currently receiving benefits, including claims that have been incurred but are not yet reported, as well as policyholders that are not yet receiving benefits. Future policy benefits reserves are comprised of the liability for future policyholder benefits (LFPB) which is reflected as Insurance reserves: Future policy benefits on the Condensed Consolidated Balance Sheet. The determination of Future policy benefits reserves requires management to make estimates and assumptions about expected policyholder experience over the remaining life of the policy. Since policies may be in force for several decades, these assumptions are subject to significant estimation risk. As a result of this variability, the Company’s future policy benefits reserves may be subject to material increases if actual experience develops adversely to the Company’s expectations. Annually in the third quarter, actuarial analysis is performed on policyholder morbidity, persistency, premium rate increases and expense experience. This analysis, combined with judgment, informs the setting of updated cash flow assumptions used to estimate the LFPB. Actuarial analysis includes predictive modeling, actual to expected experience comparisons and trend analysis. Applicable industry research is also considered. The cash flow assumption updates for the third quarter of 2024 resulted in a $15 million pretax increase in the LFPB. Included in the assumption updates was a favorable impact from outperformance on premium rate assumptions and unfavorable impact from higher cost of care inflation. The cash flow assumption updates for the third quarter 2023 resulted in an $8 million pretax increase to the LFPB. Persistency updates were unfavorable due to revisions to lapse rates. Morbidity updates were favorable driven by claim severity assumption updates, and there was a favorable impact from outperformance on premium rate assumptions. See Note A to the Consolidated Financial Statements within CNAF's Annual Report on Form 10-K for the year ended December 31, 2023 for further information on the long-term care reserving process. The following table summarizes balances and changes in the LFPB. (In millions) 2024 2023 Present value of future net premiums Balance, January 1 $ 3,710 $ 3,993 Effect of changes in discount rate (125) (74) Balance, January 1, at original locked in discount rate 3,585 3,919 Effect of changes in cash flow assumptions (1) 111 28 Effect of actual variances from expected experience (1) (40) (112) Adjusted balance, January 1 3,656 3,835 Interest accrual 139 153 Net premiums: earned during period (317) (332) Balance, end of period at original locked in discount rate 3,478 3,656 Effect of changes in discount rate 147 (67) Balance, September 30 $ 3,625 $ 3,589 Present value of future benefits & expenses Balance, January 1 $ 17,669 $ 17,472 Effect of changes in discount rate (578) (125) Balance, January 1, at original locked in discount rate 17,091 17,347 Effect of changes in cash flow assumptions (1) 126 36 Effect of actual variances from expected experience (1) 33 (45) Adjusted balance, January 1 17,250 17,338 Interest accrual 693 723 Benefit & expense payments (883) (945) Balance, end of period at original locked in discount rate 17,060 17,116 Effect of changes in discount rate 612 (873) Balance, September 30 $ 17,672 $ 16,243 Net LFPB $ 14,047 $ 12,654 (1) As of September 30, 2024 and 2023 the re-measurement gain (loss) of $(88) million and $(75) million presented parenthetically on the Condensed Consolidated Statement of Operations is comprised of the effect of changes in cash flow assumptions and the effect of actual variances from expected experience. The following table presents earned premiums and interest expense associated with the Company’s long-term care business recognized on the Condensed Consolidated Statement of Operations. Periods ended September 30 Three Months Nine Months (In millions) 2024 2023 2024 2023 Earned premiums $ 110 $ 112 $ 329 $ 340 Interest expense 185 191 554 570 The following table presents undiscounted expected future benefit and expense payments, and undiscounted expected future gross premiums. As of September 30 (In millions) 2024 2023 Expected future benefit and expense payments $ 32,009 $ 33,217 Expected future gross premiums 5,305 5,557 Discounted expected future gross premiums at the upper-medium grade fixed income instrument yield discount rate were $3,792 million and $3,711 million as of September 30, 2024 and 2023. The weighted average effective duration of the LFPB calculated using the original locked in discount rate was 11 years and 12 years as of September 30, 2024 and 2023. The weighted average interest rates in the table below are calculated based on the rate used to discount all future cash flows. As of September 30 As of December 31 2024 2023 2023 Original locked in discount rate 5.20 % 5.24 % 5.22 % Upper-medium grade fixed income instrument discount rate 4.90 5.78 4.94 For the three and nine months ended September 30, 2024, immediate charges to net income resulting from adverse development that caused the Net Premium Ratio (NPR) to exceed 100% for certain cohorts were $84 million and $128 million. For the three and nine months ended September 30, 2023, immediate charges to net income resulting from adverse development that caused the NPR to exceed 100% were $109 million and $152 million. For the three and nine months ended September 30, 2024, the portion of losses recognized in a prior period due to NPR exceeding 100% for certain cohorts which, due to favorable development, was reversed through net income was $20 million and $28 million. For the three and nine months ended September 30, 2023, the portion of losses recognized in a prior period due to NPR exceeding 100% which, due to favorable development, was reversed through net income was $26 million and $37 million.

Legal Proceedings, Contingencie

Legal Proceedings, Contingencies and Guarantees	9 Months Ended
	Sep. 30, 2024
Legal Proceedings, Commitments and Contingencies, and Guarantees [Abstract]
Legal Proceedings, Contingencies and Guarantees	Legal Proceedings, Contingencies and Guarantees The Company is a party to various claims and litigation incidental to its business, which, based on the facts and circumstances currently known, are not material to the Company's results of operations or financial position. Guarantees The Company has provided guarantees, if the primary obligor fails to perform, to holders of structured settlement annuities issued by a previously owned subsidiary. As of September 30, 2024, the potential amount of future payments the Company could be required to pay under these guarantees was approximately $1.4 billion, which will be paid over the lifetime of the annuitants. The Company does not believe any payment is likely under these guarantees, as the Company is the beneficiary of a trust that must be maintained at a level that approximates the discounted reserves for these annuities.

Benefit Plans

Benefit Plans	9 Months Ended
	Sep. 30, 2024
Retirement Benefits [Abstract]
Benefit Plans	Benefit Plans The components of net periodic pension cost (benefit) are presented in the following table. Periods ended September 30 Three Months Nine Months (In millions) 2024 2023 2024 2023 Net periodic pension cost (benefit) Interest cost on projected benefit obligation $ 21 $ 25 $ 65 $ 74 Expected return on plan assets (29) (29) (87) (89) Amortization of net actuarial loss 7 7 21 24 Pension settlement transaction loss (gain) 4 — 4 — Total net periodic pension cost (benefit) $ 3 $ 3 $ 3 $ 9 The following table indicates the line items in which the non-service cost (benefit) is presented in the Condensed Consolidated Statements of Operations. Periods ended September 30 Three Months Nine Months (In millions) 2024 2023 2024 2023 Non-Service Cost (Benefit): Insurance claims and policyholder's benefits $ 1 $ 1 $ 1 $ 2 Other operating expenses 2 2 2 7 Total net periodic pension cost (benefit) $ 3 $ 3 $ 3 $ 9 In the third quarter of 2024, a subsidiary of CNAF, as a sponsor of the CNA Canada Employee Pension Plan (the Canada Plan), purchased a nonparticipating single premium group annuity contract, under which the defined benefit pension obligation of the Canada Plan was transferred in full to an insurance company counterparty. As a result of the transaction, the Company recognized a one-time, non-cash, pretax pension settlement charge of $4 million ($3 million after-tax).

Accumulated Other Comprehensive

Accumulated Other Comprehensive Income (Loss) by Component	9 Months Ended
	Sep. 30, 2024
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Accumulated Other Comprehensive Income (Loss) by Component	Accumulated Other Comprehensive Income (Loss) by Component The tables below display the changes in Accumulated other comprehensive income (loss) by component. (In millions) Net unrealized gains (losses) on investments with an allowance for credit losses Net unrealized gains (losses) on other investments Pension and postretirement benefits Cumulative impact of changes in discount rates used to measure long duration contracts Cumulative foreign currency translation adjustment Total Balance as of July 1, 2024 $ (10) $ (2,074) $ (513) $ 255 $ (205) $ (2,547) Other comprehensive income (loss) before reclassifications (9) 1,254 — (623) 63 685 Amounts reclassified from accumulated other comprehensive income (loss) net of tax (expense) benefit of $2, $3, $3, $—, $— and $8 (6) (11) (8) — — (25) Other comprehensive income (loss) net of tax (expense) benefit of $1, $(340), $(3), $165, $— and $(177) (3) 1,265 8 (623) 63 710 Balance as of September 30, 2024 $ (13) $ (809) $ (505) $ (368) $ (142) $ (1,837) (In millions) Net unrealized gains (losses) on investments with an allowance for credit losses Net unrealized gains (losses) on other investments Pension and postretirement benefits Cumulative impact of changes in discount rates used to measure long duration contracts Cumulative foreign currency translation adjustment Total Balance as of July 1, 2023 $ (16) $ (2,481) $ (577) $ (181) $ (170) $ (3,425) Other comprehensive income (loss) before reclassifications (9) (1,105) — 818 (55) (351) Amounts reclassified from accumulated other comprehensive income (loss) net of tax (expense) benefit of $2, $6, $1, $—, $— and $9 (8) (21) (6) — — (35) Other comprehensive income (loss) net of tax (expense) benefit of $1, $289, $(1), $(217), $— and $72 (1) (1,084) 6 818 (55) (316) Balance as of September 30, 2023 $ (17) $ (3,565) $ (571) $ 637 $ (225) $ (3,741) (In millions) Net unrealized gains (losses) on investments with an allowance for credit losses Net unrealized gains (losses) on other investments Pension and postretirement benefits Cumulative impact of changes in discount rates used to measure long duration contracts Cumulative foreign currency translation adjustment Total Balance as of January 1, 2024 $ (12) $ (1,613) $ (525) $ (359) $ (163) $ (2,672) Other comprehensive income (loss) before reclassifications (14) 765 — (9) 21 763 Amounts reclassified from accumulated other comprehensive income (loss) net of tax (expense) benefit of $4, $10, $5, $—, $— and $19 (13) (39) (20) — — (72) Other comprehensive income (loss) net of tax (expense) benefit of $—, $(216), $(5), $2, $— and $(219) (1) 804 20 (9) 21 835 Balance as of September 30, 2024 $ (13) $ (809) $ (505) $ (368) $ (142) $ (1,837) (In millions) Net unrealized gains (losses) on investments with an allowance for credit losses Net unrealized gains (losses) on other investments Pension and postretirement benefits Cumulative impact of changes in discount rates used to measure long duration contracts Cumulative foreign currency translation adjustment Total Balance as of January 1, 2023, as previously reported $ (7) $ (2,738) $ (591) $ — $ (221) $ (3,557) Cumulative effect adjustment from changes in accounting guidance, net of tax (expense) benefit of $—, $—, $—, $11, $— and $11 — — — (41) — (41) Balance as of January 1, 2023 (7) (2,738) (591) (41) (221) (3,598) Other comprehensive income (loss) before reclassifications (25) (880) — 678 (4) (231) Amounts reclassified from accumulated other comprehensive income (loss) net of tax (expense) benefit of $4, $14, $5, $—, $— and $23 (15) (53) (20) — — (88) Other comprehensive income (loss) net of tax (expense) benefit of $3, $221, $(5), $(180), $— and $39 (10) (827) 20 678 (4) (143) Balance as of September 30, 2023 $ (17) $ (3,565) $ (571) $ 637 $ (225) $ (3,741) Amounts reclassified from Accumulated other comprehensive income (loss) shown above are reported in Net income (loss) as follows: Component of AOCI Condensed Consolidated Statements of Operations Line Item Affected by Reclassifications Net unrealized gains (losses) on investments with an allowance for credit losses and Net unrealized gains (losses) on other investments Net investment gains (losses) Pension and postretirement benefits Other operating expenses and Insurance claims and policyholders' benefits

Business Segments

Business Segments	9 Months Ended
	Sep. 30, 2024
Segment Reporting [Abstract]
Business Segments	Business Segments The Company's property and casualty commercial insurance operations are managed and reported in three business segments: Specialty, Commercial and International. These three segments are collectively referred to as Property & Casualty Operations. The Company's operations outside of Property & Casualty Operations are managed and reported in two segments: Life & Group and Corporate & Other. The accounting policies of the segments are the same as those described in Note A to the Consolidated Financial Statements within CNAF's Annual Report on Form 10-K for the year ended December 31, 2023. The Company manages most of its assets on a legal entity basis, while segment operations are generally conducted across legal entities. As such, only Insurance and Reinsurance receivables, Insurance reserves, Deferred acquisition costs, Goodwill and Deferred non-insurance warranty acquisition expense and revenue are readily identifiable for individual segments. Distinct investment portfolios are not maintained for every individual segment; accordingly, allocation of assets to each segment is not performed. Therefore, a significant portion of Net investment income is allocated primarily based on each segment's net carried insurance reserves, as adjusted. All significant intersegment income and expense have been eliminated. Income taxes have been allocated on the basis of the taxable income of the segments. In the following tables, certain financial measures are presented to provide information used by management to monitor the Company's operating performance. Management utilizes these financial measures to monitor the Company's insurance operations and investment portfolio. The performance of the Company's insurance operations is monitored by management through core income (loss), which is derived from certain income statement amounts. The Company's investment portfolio is monitored by management through analysis of various factors including unrealized gains and losses on securities, portfolio duration and exposure to market and credit risk. Core income (loss) is calculated by excluding from net income (loss) the after-tax effects of net investment gains or losses and gains or losses resulting from pension settlement transactions. Net investment gains or losses are excluded from the calculation of core income (loss) because they are generally driven by economic factors that are not necessarily reflective of the Company's primary operations. The calculation of core income (loss) excludes gains or losses resulting from pension settlement transactions as they result from decisions regarding the Company's defined benefit pension plans which are unrelated to the Company's primary operations. The Company's results of operations and selected balance sheet items by segment are presented in the following tables. Three months ended September 30, 2024 Specialty Commercial International Life & Corporate (In millions) Eliminations Total Operating revenues Net earned premiums $ 848 $ 1,325 $ 311 $ 110 $ — $ (1) $ 2,593 Net investment income 157 183 32 240 14 — 626 Non-insurance warranty revenue 401 — — — — — 401 Other revenues 1 5 — — 3 (1) 8 Total operating revenues 1,407 1,513 343 350 17 (2) 3,628 Claims, benefits and expenses Net incurred claims and benefits 509 954 195 336 16 — 2,010 Policyholders’ dividends 2 7 — — — — 9 Amortization of deferred acquisition costs 188 209 60 — — — 457 Non-insurance warranty expense 387 — — — — — 387 Other insurance related expenses 90 158 44 30 — (1) 321 Other expenses 13 8 (8) 1 56 (1) 69 Total claims, benefits and expenses (1) 1,189 1,336 291 367 72 (2) 3,253 Core income (loss) before income tax 218 177 52 (17) (55) — 375 Income tax (expense) benefit on core income (loss) (47) (38) (16) 8 11 — (82) Core income (loss) $ 171 $ 139 $ 36 $ (9) $ (44) $ — 293 Net investment gains (losses) (10) Income tax (expense) benefit on net investment gains (losses) 3 Net investment gains (losses), after tax (7) Pension settlement transaction gains (losses) (4) Income tax (expense) benefit on pension settlement transaction gains (losses) 1 Pension settlement transaction gains (losses), after tax (3) Net income (loss) $ 283 (1) Excludes the impact of pension settlement transaction gains (losses). See Note H to the Condensed Consolidated Financial Statements for additional information. Three months ended September 30, 2023 Specialty Commercial International Life & Corporate (In millions) Eliminations Total Operating revenues Net earned premiums $ 829 $ 1,170 $ 296 $ 112 $ — $ (1) $ 2,406 Net investment income 136 156 26 216 19 — 553 Non-insurance warranty revenue 407 — — — — — 407 Other revenues — 9 (1) — 2 (2) 8 Total operating revenues 1,372 1,335 321 328 21 (3) 3,374 Claims, benefits and expenses Net incurred claims and benefits 480 807 178 343 10 — 1,818 Policyholders’ dividends 2 6 — — — — 8 Amortization of deferred acquisition costs 175 188 63 — — — 426 Non-insurance warranty expense 386 — — — — — 386 Other insurance related expenses 89 156 20 29 1 (1) 294 Other expenses 13 11 6 (1) 51 (2) 78 Total claims, benefits and expenses 1,145 1,168 267 371 62 (3) 3,010 Core income (loss) before income tax 227 167 54 (43) (41) — 364 Income tax (expense) benefit on core income (loss) (49) (34) (14) 14 8 — (75) Core income (loss) $ 178 $ 133 $ 40 $ (29) $ (33) $ — 289 Net investment gains (losses) (38) Income tax (expense) benefit on net investment gains (losses) 7 Net investment gains (losses), after tax (31) Net income (loss) $ 258 Nine months ended September 30, 2024 Specialty Commercial International Life & Corporate (In millions) Eliminations Total Operating revenues Net earned premiums $ 2,493 $ 3,774 $ 937 $ 329 $ — $ (1) $ 7,532 Net investment income 461 534 95 710 53 — 1,853 Non-insurance warranty revenue 1,212 — — — — — 1,212 Other revenues 1 23 — — 9 (7) 26 Total operating revenues 4,167 4,331 1,032 1,039 62 (8) 10,623 Claims, benefits and expenses Net incurred claims and benefits 1,478 2,628 568 973 35 — 5,682 Policyholders’ dividends 7 19 — — — — 26 Amortization of deferred acquisition costs 546 608 182 — — — 1,336 Non-insurance warranty expense 1,169 — — — — — 1,169 Other insurance related expenses 267 454 129 88 — (1) 937 Other expenses 41 33 (5) 2 173 (7) 237 Total claims, benefits and expenses (1) 3,508 3,742 874 1,063 208 (8) 9,387 Core income (loss) before income tax 659 589 158 (24) (146) — 1,236 Income tax (expense) benefit on core income (loss) (142) (125) (41) 19 27 — (262) Core income (loss) $ 517 $ 464 $ 117 $ (5) $ (119) $ — 974 Net investment gains (losses) (42) Income tax (expense) benefit on net investment gains (losses) 9 Net investment gains (losses), after tax (33) Pension settlement transaction gains (losses) (4) Income tax (expense) benefit on pension settlement transaction gains (losses) 1 Pension settlement transaction gains (losses), after tax (3) Net income (loss) $ 938 September 30, 2024 (In millions) Reinsurance receivables $ 1,509 $ 1,456 $ 533 $ 86 $ 2,236 $ — $ 5,820 Insurance receivables 986 2,149 375 3 1 — 3,514 Deferred acquisition costs 413 400 130 — — — 943 Goodwill 117 — 30 — — — 147 Deferred non-insurance warranty acquisition expense 3,571 — — — — — 3,571 Insurance reserves Claim and claim adjustment expenses 7,328 11,018 2,990 650 2,572 — 24,558 Unearned premiums 3,218 3,186 755 100 — — 7,259 Future policy benefits — — — 14,047 — — 14,047 Deferred non-insurance warranty revenue 4,594 — — — — — 4,594 (1) Excludes the impact of pension settlement transaction gains (losses). See Note H to the Condensed Consolidated Financial Statements for additional information. Nine months ended September 30, 2023 Specialty Commercial International Life & Corporate (In millions) Eliminations Total Operating revenues Net earned premiums $ 2,438 $ 3,336 $ 888 $ 340 $ — $ (1) $ 7,001 Net investment income 407 470 74 659 43 — 1,653 Non-insurance warranty revenue 1,221 — — — — — 1,221 Other revenues — 22 — — 7 (7) 22 Total operating revenues 4,066 3,828 962 999 50 (8) 9,897 Claims, benefits and expenses Net incurred claims and benefits 1,419 2,235 552 998 32 — 5,236 Policyholders’ dividends 5 17 — — — — 22 Amortization of deferred acquisition costs 508 532 168 — — — 1,208 Non-insurance warranty expense 1,154 — — — — — 1,154 Other insurance related expenses 269 456 102 89 2 (1) 917 Other expenses 39 27 2 — 136 (7) 197 Total claims, benefits and expenses 3,394 3,267 824 1,087 170 (8) 8,734 Core income (loss) before income tax 672 561 138 (88) (120) — 1,163 Income tax (expense) benefit on core income (loss) (146) (118) (36) 36 23 — (241) Core income (loss) $ 526 $ 443 $ 102 $ (52) $ (97) $ — 922 Net investment gains (losses) (105) Income tax (expense) benefit on net investment gains (losses) 21 Net investment gains (losses), after tax (84) Net income (loss) $ 838 December 31, 2023 (In millions) Reinsurance receivables $ 1,281 $ 1,218 $ 468 $ 93 $ 2,374 $ — $ 5,434 Insurance receivables 1,053 2,024 388 5 — — 3,470 Deferred acquisition costs 392 371 133 — — — 896 Goodwill 117 — 29 — — — 146 Deferred non-insurance warranty acquisition expense 3,661 — — — — — 3,661 Insurance reserves Claim and claim adjustment expenses 7,131 10,103 2,709 675 2,686 — 23,304 Unearned premiums 3,227 2,858 749 99 — — 6,933 Future policy benefits — — — 13,959 — — 13,959 Deferred non-insurance warranty revenue 4,694 — — — — — 4,694 The following table presents operating revenues by line of business for each reportable segment. Periods ended September 30 Three Months Nine Months (In millions) 2024 2023 2024 2023 Specialty Management & Professional Liability $ 753 $ 723 $ 2,215 $ 2,146 Surety 202 189 580 540 Warranty & Alternative Risks 452 460 1,372 1,380 Specialty revenues 1,407 1,372 4,167 4,066 Commercial Middle Market 448 437 1,307 1,254 Construction 521 444 1,459 1,249 Small Business 161 160 472 470 Other Commercial 383 294 1,093 855 Commercial revenues 1,513 1,335 4,331 3,828 International Canada 99 98 296 287 Europe 150 139 440 401 Hardy 94 84 296 274 International revenues 343 321 1,032 962 Life & Group revenues 350 328 1,039 999 Corporate & Other revenues 17 21 62 50 Eliminations (2) (3) (8) (8) Total operating revenues 3,628 3,374 10,623 9,897 Net investment gains (losses) (10) (38) (42) (105) Total revenues $ 3,618 $ 3,336 $ 10,581 $ 9,792

Non-Insurance Revenues from Con

Non-Insurance Revenues from Contracts with Customers	9 Months Ended
	Sep. 30, 2024
Revenue from Contract with Customer [Abstract]
Non-Insurance Revenues from Contracts with Customers	Non-Insurance Revenues from Contracts with Customers The Company had a deferred non-insurance warranty revenue balance of $4.6 billion and $4.7 billion reported under Liabilities as of September 30, 2024 and December 31, 2023. For the three and nine months ended September 30, 2024, the Company recognized $0.3 billion and $1.1 billion of revenues in each period that were included in the deferred revenue balance as of January 1, 2024. For the three and nine months ended September 30, 2023, the Company recognized $0.2 billion and $0.9 billion of revenues that were included in the deferred revenue balance as of January 1, 2023. For the three and nine months ended September 30, 2024 and 2023, non-insurance warranty revenue recognized from performance obligations related to prior periods due to a change in estimate was not material . The Company expects to recognize approximately $0.4 billion of the deferred revenue in the remainder of 2024, $1.3 billion in 2025, $1.0 billion in 2026 and $1.9 billion thereafter.

Subsequent Event

Subsequent Event	9 Months Ended
	Sep. 30, 2024
Subsequent Events [Abstract]
Subsequent Event	Subsequent Events CNA Employee Retirement Plan Trust Settlement Transaction In October of 2024, a subsidiary of CNAF, as a sponsor of the CNA Employee Retirement Plan Trust (the Plan), entered into a commitment agreement, with Metropolitan Life Insurance Company (the Insurer) under which the Plan purchased a nonparticipating single premium group annuity contract that transferred to the Insurer approximately $1,045 million of the Plan’s defined benefit pension obligations. The group annuity contract covers approximately 7,600 Plan participants and beneficiaries (the Transferred Participants), representing approximately 60% of the Plan’s obligations. Under the group annuity contract, the Insurer has made an irrevocable commitment, and will be solely responsible, to pay the pension benefits of each Transferred Participant that are due on and after January 1, 2025. The purchase of the group annuity contract was funded directly by assets of the Plan and required no cash or asset contributions of the Company. As a result of the transaction, the Company will recognize a one-time, non-cash, pretax pension settlement charge of approximately $370 million ($290 million after-tax) in the fourth quarter of 2024. This charge is largely driven by the accelerated recognition of the Company’s actuarial pension loss from accumulated other comprehensive income into net income, which does not impact stockholder’s equity. This charge will not impact the Company’s fourth quarter or full year 2024 core income (loss) or cash flow. Fourth Quarter 2024 Hurricane Milton Estimates

General (Policies)

General (Policies)	9 Months Ended
	Sep. 30, 2024
Accounting Policies [Abstract]
Basis of Presentation	The Condensed Consolidated Financial Statements include the accounts of CNA Financial Corporation (CNAF) and its subsidiaries. Collectively, CNAF and its subsidiaries are referred to as CNA or the Company. Loews Corporation (Loews) owned approximately 92% of the outstanding common stock of CNAF as of September 30, 2024.
Use of Estimates	The preparation of Condensed Consolidated Financial Statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the Condensed Consolidated Financial Statements and the reported amounts of revenues and expenses during the reporting period. Actual results may differ from those estimates.The interim financial data as of September 30, 2024 and for the three and nine months ended September 30, 2024 and 2023 is unaudited. However, in the opinion of management, the interim data includes all adjustments, including normal recurring adjustments, necessary for a fair statement of the Company's results for the interim periods in accordance with GAAP. The results of operations for the interim periods are not necessarily indicative of the results to be expected for the full year.
Accounting Standards Pending Adoption	In November 2023, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) No. 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures . The updated accounting guidance requires expanded reportable segment disclosures, primarily related to significant segment expenses which are regularly provided to the Company’s Chief Operating Decision Maker (CODM). The guidance is effective for fiscal years beginning after December 15, 2023, and interim periods within annual periods beginning after December 15, 2024. Retrospective application is required. The Company is currently evaluating the effect the updated guidance will have on its financial statement disclosures and expects to disclose additional quantitative and qualitative information related to segment expenses regularly provided to the CODM that are included in the Company's measure of segment profit or loss, which is core income (loss). In December 2023, the FASB issued ASU No. 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures . The updated accounting guidance requires expanded income tax disclosures, including the disaggregation of existing disclosures related to the tax rate reconciliation and income taxes paid. The guidance is effective for annual periods beginning after December 15, 2024. Prospective application is required, with retrospective application permitted. The Company is currently evaluating the effect the updated guidance will have on the Company's financial statement disclosures.
Earnings (Loss) Per Share Data	Earnings (loss) per share is based on weighted average number of outstanding common shares. Basic earnings (loss) per share excludes the impact of dilutive securities and is computed by dividing Net income (loss) by the weighted average number of common shares outstanding for the period. Diluted earnings (loss) per share reflects the potential dilution that could occur if securities or other contracts to issue common stock were exercised or converted into common stock.
Future policy benefits reserves	Future Policy Benefits Reserves Future policy benefits reserves are associated with the Company's run-off long-term care business, included in the Life & Group segment, and relate to policyholders that are currently receiving benefits, including claims that have been incurred but are not yet reported, as well as policyholders that are not yet receiving benefits. Future policy benefits reserves are comprised of the liability for future policyholder benefits (LFPB) which is reflected as Insurance reserves: Future policy benefits on the Condensed Consolidated Balance Sheet. The determination of Future policy benefits reserves requires management to make estimates and assumptions about expected policyholder experience over the remaining life of the policy. Since policies may be in force for several decades, these assumptions are subject to significant estimation risk. As a result of this variability, the Company’s future policy benefits reserves may be subject to material increases if actual experience develops adversely to the Company’s expectations. Annually in the third quarter, actuarial analysis is performed on policyholder morbidity, persistency, premium rate increases and expense experience. This analysis, combined with judgment, informs the setting of updated cash flow assumptions used to estimate the LFPB. Actuarial analysis includes predictive modeling, actual to expected experience comparisons and trend analysis. Applicable industry research is also considered. The cash flow assumption updates for the third quarter of 2024 resulted in a $15 million pretax increase in the LFPB. Included in the assumption updates was a favorable impact from outperformance on premium rate assumptions and unfavorable impact from higher cost of care inflation. The cash flow assumption updates for the third quarter 2023 resulted in an $8 million pretax increase to the LFPB. Persistency updates were unfavorable due to revisions to lapse rates. Morbidity updates were favorable driven by claim severity assumption updates, and there was a favorable impact from outperformance on premium rate assumptions. See Note A to the Consolidated Financial Statements within CNAF's Annual Report on Form 10-K for the year ended December 31, 2023 for further information on the long-term care reserving process.

Earnings (Loss) Per Share Data

Earnings (Loss) Per Share Data (Tables)	9 Months Ended
	Sep. 30, 2024
Earnings Per Share [Abstract]
Schedule of Earnings Per Share, Basic and Diluted	The following table presents the income and share data used in the basic and diluted earnings per share computations. Periods ended September 30 Three Months Nine Months (In millions, except per share data) 2024 2023 2024 2023 Net income (loss) $ 283 $ 258 $ 938 $ 838 Common Stock and Common Stock Equivalents Basic Weighted average shares outstanding 271.3 271.2 271.5 271.2 Diluted Weighted average shares outstanding 271.3 271.2 271.5 271.2 Dilutive effect of stock-based awards under compensation plans 1.4 1.1 1.2 1.0 Total 272.7 272.3 272.7 272.2 Earnings (loss) per share Basic $ 1.04 $ 0.95 $ 3.46 $ 3.09 Diluted $ 1.04 $ 0.95 $ 3.44 $ 3.08

Investments (Tables)

Investments (Tables)	9 Months Ended
	Sep. 30, 2024
Investments [Abstract]
Net investment income	The significant components of Net investment income are presented in the following table. Periods ended September 30 Three Months Nine Months (In millions) 2024 2023 2024 2023 Fixed maturity securities $ 517 $ 491 $ 1,530 $ 1,443 Equity securities 21 9 56 42 Limited partnership investments 67 28 195 108 Mortgage loans 14 15 43 43 Short-term investments 20 23 68 51 Trading portfolio — 1 1 4 Other 8 6 23 20 Gross investment income 647 573 1,916 1,711 Investment expense (21) (20) (63) (58) Net investment income $ 626 $ 553 $ 1,853 $ 1,653 Net investment income (loss) recognized due to the change in fair value of common stock held as of September 30, 2024 and 2023 $ 11 $ (3) $ 20 $ 2
Net realized investment gains (losses)	Net investment gains (losses) are presented in the following table. Periods ended September 30 Three Months Nine Months (In millions) 2024 2023 2024 2023 Net investment gains (losses): Fixed maturity securities: Gross gains $ 11 $ 12 $ 38 $ 55 Gross losses (33) (49) (104) (141) Net investment gains (losses) on fixed maturity securities (22) (37) (66) (86) Equity securities 13 2 25 (9) Mortgage loans — (5) — (11) Short-term investments and other (1) 2 (1) 1 Net investment gains (losses) $ (10) $ (38) $ (42) $ (105) Net investment gains (losses) recognized due to the change in fair value of non-redeemable preferred stock held as of September 30, 2024 and 2023 $ 13 $ 2 $ 24 $ 2
Components of net other than temporary impairment losses recognized in earnings by asset type	The table includes losses (gains) on securities with an intention to sell and changes in the allowance for credit losses on securities since acquisition date. Periods ended September 30 Three Months Nine Months (In millions) 2024 2023 2024 2023 Fixed maturity securities available-for-sale: Corporate and other bonds $ 8 $ 8 $ 23 $ 25 Asset-backed 4 4 9 12 Impairment losses (gains) recognized in earnings $ 12 $ 12 $ 32 $ 37
Summary of fixed maturity securities	The following tables present a summary of fixed maturity securities. September 30, 2024 Cost or Gross Gross Allowance for Credit Losses Estimated (In millions) Fixed maturity securities available-for-sale: Corporate and other bonds $ 25,872 $ 826 $ 900 $ 6 $ 25,792 States, municipalities and political subdivisions 7,406 359 617 — 7,148 Asset-backed: Residential mortgage-backed 3,684 32 362 — 3,354 Commercial mortgage-backed 1,867 15 141 — 1,741 Other asset-backed 3,743 40 186 12 3,585 Total asset-backed 9,294 87 689 12 8,680 U.S. Treasury and obligations of government-sponsored enterprises 224 2 4 — 222 Foreign government 755 8 26 — 737 Total fixed maturity securities available-for-sale 43,551 1,282 2,236 18 42,579 Total fixed maturity securities trading — — — — — Total fixed maturity securities $ 43,551 $ 1,282 $ 2,236 $ 18 $ 42,579 December 31, 2023 Cost or Gross Gross Allowance for Credit Losses Estimated (In millions) Fixed maturity securities available-for-sale: Corporate and other bonds $ 25,020 $ 597 $ 1,345 $ 4 $ 24,268 States, municipalities and political subdivisions 7,713 382 703 — 7,392 Asset-backed: Residential mortgage-backed 3,411 16 425 — 3,002 Commercial mortgage-backed 1,862 7 230 8 1,631 Other asset-backed 3,515 13 256 4 3,268 Total asset-backed 8,788 36 911 12 7,901 U.S. Treasury and obligations of government-sponsored enterprises 152 1 2 — 151 Foreign government 741 6 34 — 713 Total fixed maturity securities available-for-sale 42,414 1,022 2,995 16 40,425 Total fixed maturity securities trading — — — — — Total fixed maturity securities $ 42,414 $ 1,022 $ 2,995 $ 16 $ 40,425
Debt securities, available-for-sale, unrealized loss position, fair value	The following tables present the estimated fair value and gross unrealized losses of available-for-sale fixed maturity securities in a gross unrealized loss position for which an allowance for credit loss has not been recorded, by the length of time in which the securities have continuously been in that position. Less than 12 Months 12 Months or Longer Total September 30, 2024 Estimated Gross Estimated Gross Estimated Gross (In millions) Fixed maturity securities available-for-sale: Corporate and other bonds $ 1,664 $ 31 $ 11,240 $ 869 $ 12,904 $ 900 States, municipalities and political subdivisions 422 7 3,155 610 3,577 617 Asset-backed: Residential mortgage-backed 130 2 2,162 360 2,292 362 Commercial mortgage-backed 112 — 1,134 141 1,246 141 Other asset-backed 151 4 1,638 182 1,789 186 Total asset-backed 393 6 4,934 683 5,327 689 U.S. Treasury and obligations of government-sponsored enterprises 45 2 45 2 90 4 Foreign government 99 1 403 25 502 26 Total $ 2,623 $ 47 $ 19,777 $ 2,189 $ 22,400 $ 2,236 Less than 12 Months 12 Months or Longer Total December 31, 2023 Estimated Gross Estimated Gross Estimated Gross (In millions) Fixed maturity securities available-for-sale: Corporate and other bonds $ 1,943 $ 37 $ 13,406 $ 1,308 $ 15,349 $ 1,345 States, municipalities and political subdivisions 598 18 3,104 685 3,702 703 Asset-backed: Residential mortgage-backed 233 4 2,212 421 2,445 425 Commercial mortgage-backed 200 5 1,184 225 1,384 230 Other asset-backed 392 8 1,869 248 2,261 256 Total asset-backed 825 17 5,265 894 6,090 911 U.S. Treasury and obligations of government-sponsored enterprises 65 1 23 1 88 2 Foreign government 52 1 450 33 502 34 Total $ 3,483 $ 74 $ 22,248 $ 2,921 $ 25,731 $ 2,995 The following table presents the estimated fair value and gross unrealized losses of available-for-sale fixed maturity securities in a gross unrealized loss position for which an allowance for credit loss has not been recorded, by ratings distribution. September 30, 2024 December 31, 2023 (In millions) Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses U.S. Government, Government agencies and Government-sponsored enterprises $ 2,127 $ 265 $ 2,273 $ 309 AAA 1,277 221 1,524 261 AA 3,641 547 3,817 658 A 5,229 405 5,652 517 BBB 9,243 689 11,523 1,095 Non-investment grade 883 109 942 155 Total $ 22,400 $ 2,236 $ 25,731 $ 2,995
Debt securities, available-for-sale, allowance for credit loss	The following tables present the activity related to the allowance on available-for-sale securities with credit impairments and purchased credit-deteriorated (PCD) assets. Accrued interest receivable on available-for-sale fixed maturity securities totaled $451 million, $435 million, and $430 million as of September 30, 2024, December 31, 2023, and September 30, 2023 and is excluded from the estimate of expected credit losses and the amortized cost basis in the tables included within this Note. (In millions) Corporate and other bonds Asset-backed Total Allowance for credit losses: Balance as of July 1, 2024 $ — $ 17 $ 17 Additions to the allowance for credit losses: Securities for which credit losses were not previously recorded 4 — 4 Available-for-sale securities accounted for as PCD assets 2 — 2 Reductions to the allowance for credit losses: Securities sold during the period (realized) — — — Intent to sell or more likely than not will be required to sell the security before recovery of its amortized cost basis — — — Write-offs charged against the allowance — 9 9 Recoveries of amounts previously written off — — — Additional increases or (decreases) to the allowance for credit losses on securities that had an allowance recorded in a previous period — 4 4 Balance as of September 30, 2024 $ 6 $ 12 $ 18 (In millions) Corporate and other bonds Asset-backed Total Allowance for credit losses: Balance as of July 1, 2023 $ 13 $ 9 $ 22 Additions to the allowance for credit losses: Securities for which credit losses were not previously recorded 5 — 5 Available-for-sale securities accounted for as PCD assets 2 — 2 Reductions to the allowance for credit losses: Securities sold during the period (realized) — — — Intent to sell or more likely than not will be required to sell the security before recovery of its amortized cost basis — — — Write-offs charged against the allowance 15 — 15 Recoveries of amounts previously written off — — — Additional increases or (decreases) to the allowance for credit losses on securities that had an allowance recorded in a previous period — 4 4 Balance as of September 30, 2023 $ 5 $ 13 $ 18 (In millions) Corporate and other bonds Asset-backed Total Allowance for credit losses: Balance as of January 1, 2024 $ 4 $ 12 $ 16 Additions to the allowance for credit losses: Securities for which credit losses were not previously recorded 4 — 4 Available-for-sale securities accounted for as PCD assets 2 — 2 Reductions to the allowance for credit losses: Securities sold during the period (realized) 3 1 4 Intent to sell or more likely than not will be required to sell the security before recovery of its amortized cost basis 1 — 1 Write-offs charged against the allowance — 9 9 Recoveries of amounts previously written off — — — Additional increases or (decreases) to the allowance for credit losses on securities that had an allowance recorded in a previous period — 10 10 Balance as of September 30, 2024 $ 6 $ 12 $ 18 (In millions) Corporate and other bonds Asset-backed Total Allowance for credit losses: Balance as of January 1, 2023 $ — $ 1 $ 1 Additions to the allowance for credit losses: Securities for which credit losses were not previously recorded 6 7 13 Available-for-sale securities accounted for as PCD assets 22 — 22 Reductions to the allowance for credit losses: Securities sold during the period (realized) 6 — 6 Intent to sell or more likely than not will be required to sell the security before recovery of its amortized cost basis 3 — 3 Write-offs charged against the allowance 15 — 15 Recoveries of amounts previously written off — — — Additional increases or (decreases) to the allowance for credit losses on securities that had an allowance recorded in a previous period 1 5 6 Balance as of September 30, 2023 $ 5 $ 13 $ 18
Contractual maturity	The following table presents available-for-sale fixed maturity securities by contractual maturity. September 30, 2024 December 31, 2023 (In millions) Cost or Estimated Cost or Estimated Due in one year or less $ 1,585 $ 1,565 $ 1,121 $ 1,091 Due after one year through five years 11,948 11,800 11,563 11,180 Due after five years through ten years 13,333 12,959 13,359 12,573 Due after ten years 16,685 16,255 16,371 15,581 Total $ 43,551 $ 42,579 $ 42,414 $ 40,425
Financing receivable credit quality indicators	The following table presents the amortized cost basis of mortgage loans for each credit quality indicator by year of origination. The primary credit quality indicators utilized are debt service coverage ratios (DSCR) and loan-to-value ratios (LTV). September 30, 2024 Mortgage Loans Amortized Cost Basis by Origination Year (1) (In millions) 2024 2023 2022 2021 2020 Prior Total DSCR ≥1.6x LTV less than 55% $ — $ 33 $ 9 $ 2 $ 97 $ 242 $ 383 LTV 55% to 65% — — — 5 — — 5 LTV greater than 65% — — 30 12 — — 42 DSCR 1.2x - 1.6x LTV less than 55% — 28 5 — 13 50 96 LTV 55% to 65% 43 20 36 36 4 31 170 LTV greater than 65% — 13 64 — 20 — 97 DSCR ≤1.2 LTV less than 55% — — — — — — — LTV 55% to 65% — 32 75 — — 41 148 LTV greater than 65% — — 28 21 — 48 97 Total $ 43 $ 126 $ 247 $ 76 $ 134 $ 412 $ 1,038 (1) The values in the table above reflect DSCR on a standardized amortization period and LTV based on the most recent appraised values trended forward using changes in a commercial real estate price index.

Fair Value (Tables)

Fair Value (Tables)	9 Months Ended
	Sep. 30, 2024
Fair Value Disclosures [Abstract]
Assets and liabilities measured at fair value on a recurring basis	Assets and liabilities measured at fair value on a recurring basis are presented in the following tables. Corporate bonds and other includes obligations of the United States of America (U.S.) Treasury, government-sponsored enterprises, foreign governments and redeemable preferred stock. September 30, 2024 Total (In millions) Level 1 Level 2 Level 3 Assets Fixed maturity securities: Corporate bonds and other $ 225 $ 25,289 $ 1,237 $ 26,751 States, municipalities and political subdivisions — 7,103 45 7,148 Asset-backed — 7,765 915 8,680 Total fixed maturity securities 225 40,157 2,197 42,579 Equity securities: Common stock 171 — 12 183 Non-redeemable preferred stock 47 436 2 485 Total equity securities 218 436 14 668 Short-term and other 1,691 30 — 1,721 Total assets $ 2,134 $ 40,623 $ 2,211 $ 44,968 Liabilities Other liabilities $ — $ — $ — $ — Total liabilities $ — $ — $ — $ — December 31, 2023 Total (In millions) Level 1 Level 2 Level 3 Assets Fixed maturity securities: Corporate bonds and other $ 161 $ 23,926 $ 1,045 $ 25,132 States, municipalities and political subdivisions — 7,348 44 7,392 Asset-backed — 7,000 901 7,901 Total fixed maturity securities 161 38,274 1,990 40,425 Equity securities: Common stock 167 — 24 191 Non-redeemable preferred stock 52 440 — 492 Total equity securities 219 440 24 683 Short-term and other 1,976 32 — 2,008 Total assets $ 2,356 $ 38,746 $ 2,014 $ 43,116 Liabilities Other liabilities $ — $ 1 $ — $ 1 Total liabilities $ — $ 1 $ — $ 1
Table of reconciliation for assets and liabilities measured at fair value on a recurring basis using significant unobservable inputs	The tables below present a reconciliation for all assets and liabilities measured at fair value on a recurring basis using significant unobservable inputs (Level 3). Level 3 (In millions) Corporate bonds and other States, municipalities and political subdivisions Asset-backed Equity securities Total Balance as of July 1, 2024 $ 1,129 $ 43 $ 887 $ 14 $ 2,073 Total realized and unrealized investment gains (losses): Reported in Net investment gains (losses) — — (3) — (3) Reported in Net investment income — — 4 — 4 Reported in Other comprehensive income (loss) 59 2 30 — 91 Total realized and unrealized investment gains (losses) 59 2 31 — 92 Purchases 83 — 38 — 121 Sales (10) — — — (10) Settlements (24) — (23) — (47) Transfers into Level 3 — — — — — Transfers out of Level 3 — — (18) — (18) Balance as of September 30, 2024 $ 1,237 $ 45 $ 915 $ 14 $ 2,211 Unrealized gains (losses) on Level 3 assets and liabilities held as of September 30, 2024 recognized in Net income (loss) in the period $ — $ — $ — $ — $ — Unrealized gains (losses) on Level 3 assets and liabilities held as of September 30, 2024 recognized in Other comprehensive income (loss) in the period 57 2 30 — 89 Level 3 (In millions) Corporate bonds and other States, municipalities and political subdivisions Asset-backed Equity securities Total Balance as of July 1, 2023 $ 971 $ 43 $ 883 $ 26 $ 1,923 Total realized and unrealized investment gains (losses): Reported in Net investment gains (losses) — — (4) — (4) Reported in Net investment income — — 5 (1) 4 Reported in Other comprehensive income (loss) (36) (2) (28) — (66) Total realized and unrealized investment gains (losses) (36) (2) (27) (1) (66) Purchases 29 — 61 — 90 Sales — — — (2) (2) Settlements (19) — (13) — (32) Transfers into Level 3 — — — — — Transfers out of Level 3 — — (7) — (7) Balance as of September 30, 2023 $ 945 $ 41 $ 897 $ 23 $ 1,906 Unrealized gains (losses) on Level 3 assets and liabilities held as of September 30, 2023 recognized in Net income (loss) in the period $ — $ — $ — $ (1) $ (1) Unrealized gains (losses) on Level 3 assets and liabilities held as of September 30, 2023 recognized in Other comprehensive income (loss) in the period (36) (2) (28) — (66) Level 3 (In millions) Corporate bonds and other States, municipalities and political subdivisions Asset-backed Equity securities Total Balance as of January 1, 2024 $ 1,045 $ 44 $ 901 $ 24 $ 2,014 Total realized and unrealized investment gains (losses): Reported in Net investment gains (losses) — — (10) — (10) Reported in Net investment income — — 15 6 21 Reported in Other comprehensive income (loss) 39 1 14 — 54 Total realized and unrealized investment gains (losses) 39 1 19 6 65 Purchases 229 — 111 3 343 Sales (10) — (14) (19) (43) Settlements (77) — (65) — (142) Transfers into Level 3 11 — — — 11 Transfers out of Level 3 — — (37) — (37) Balance as of September 30, 2024 $ 1,237 $ 45 $ 915 $ 14 $ 2,211 Unrealized gains (losses) on Level 3 assets and liabilities held as of September 30, 2024 recognized in Net income (loss) in the period $ — $ — $ — $ 2 $ 2 Unrealized gains (losses) on Level 3 assets and liabilities held as of September 30, 2024 recognized in Other comprehensive income (loss) in the period 34 1 14 — 49 Level 3 (In millions) Corporate bonds and other States, municipalities and political subdivisions Asset-backed Equity securities Total Balance as of January 1, 2023 $ 810 $ 43 $ 788 $ 35 $ 1,676 Total realized and unrealized investment gains (losses): Reported in Net investment gains (losses) — — (5) — (5) Reported in Net investment income — — 15 (8) 7 Reported in Other comprehensive income (loss) (27) (2) (28) — (57) Total realized and unrealized investment gains (losses) (27) (2) (18) (8) (55) Purchases 178 — 203 — 381 Sales — — — (4) (4) Settlements (27) — (39) — (66) Transfers into Level 3 11 — 23 — 34 Transfers out of Level 3 — — (60) — (60) Balance as of September 30, 2023 $ 945 $ 41 $ 897 $ 23 $ 1,906 Unrealized gains (losses) on Level 3 assets and liabilities held as of September 30, 2023 recognized in Net income (loss) in the period $ — $ — $ — $ (8) $ (8) Unrealized gains (losses) on Level 3 assets and liabilities held as of September 30, 2023 recognized in Other comprehensive income (loss) in the period (27) (2) (28) — (57)
Quantitative information about significant unobservable inputs in the fair value measurement of level 3 assets	The following tables present quantitative information about the significant unobservable inputs utilized by the Company in the fair value measurements of Level 3 assets. Valuations for assets and liabilities not presented in the tables below are primarily based on broker/dealer quotes for which there is a lack of transparency as to inputs used to develop the valuations. The quantitative detail of these unobservable inputs is neither provided nor reasonably available to the Company. The weighted average rate is calculated based on fair value. September 30, 2024 Estimated Fair Value Valuation Technique(s) Unobservable Input(s) Range Fixed maturity securities $ 1,713 Discounted cash flow Credit spread 1% - 6% (2%) December 31, 2023 Estimated Fair Value Valuation Technique(s) Unobservable Input(s) Range Fixed maturity securities $ 1,495 Discounted cash flow Credit spread 1% - 7% (2%)
Carrying amount and estimated fair value of financial instrument assets and liabilities not measured at fair value	The carrying amount and estimated fair value of the Company's financial assets and liabilities which are not measured at fair value on the Condensed Consolidated Balance Sheets are presented in the following tables. September 30, 2024 Carrying Estimated Fair Value (In millions) Level 1 Level 2 Level 3 Total Assets Mortgage loans $ 1,003 $ — $ — $ 988 $ 988 Liabilities Short-term debt $ — $ — $ — $ — $ — Long-term debt 2,972 — 2,952 — 2,952 December 31, 2023 Carrying Estimated Fair Value (In millions) Level 1 Level 2 Level 3 Total Assets Mortgage loans $ 1,035 $ — $ — $ 997 $ 997 Liabilities Short-term debt $ 550 $ — $ 546 $ — $ 546 Long-term debt 2,481 — 2,385 — 2,385

Claim and Claim Adjustment Ex_2

Claim and Claim Adjustment Expense Reserves (Tables)	9 Months Ended
	Sep. 30, 2024
Liability for Future Policy Benefits and Unpaid Claims and Claims Adjustment Expense [Abstract]
Schedule of liability for unpaid claims and claims adjustment expense	The following table presents a reconciliation between beginning and ending claim and claim adjustment expense reserves. For the nine months ended September 30 (In millions) 2024 2023 Reserves, beginning of year: Gross $ 23,304 $ 22,120 Ceded 5,141 5,191 Net reserves, beginning of year 18,163 16,929 Net incurred claim and claim adjustment expenses: Provision for insured events of current year 4,706 4,221 Increase (decrease) in provision for insured events of prior years 26 43 Amortization of discount 30 33 Total net incurred (1) 4,762 4,297 Net payments attributable to: Current year events (655) (588) Prior year events (3,189) (2,953) Total net payments (3,844) (3,541) Foreign currency translation adjustment and other 35 (30) Net reserves, end of period 19,116 17,655 Ceded reserves, end of period 5,442 5,181 Gross reserves, end of period $ 24,558 $ 22,836 (1) Total net incurred does not agree to Insurance claims and policyholders' benefits as reflected on the Condensed Consolidated Statements of Operations due to amounts related to retroactive reinsurance deferred gain accounting, uncollectible reinsurance, benefit expenses related to future policy benefits and policyholders' dividends, which are not reflected in the table above.
Net prior year development	The following table presents development recorded for the Specialty, Commercial, International and Corporate & Other segments. Periods ended September 30 Three Months Nine Months (In millions) 2024 2023 2024 2023 Pretax (favorable) unfavorable development: Specialty $ — $ (5) $ (8) $ (9) Commercial (3) (2) (11) (17) International (2) — (5) 15 Corporate & Other 22 20 57 55 Total pretax (favorable) unfavorable development $ 17 $ 13 $ 33 $ 44
Net prior year claim and allocated claim adjustment expense reserve development	The following table presents further detail of the development recorded for the Specialty segment. Periods ended September 30 Three Months Nine Months (In millions) 2024 2023 2024 2023 Pretax (favorable) unfavorable development: Medical Professional Liability $ — $ — $ (2) $ 9 Other Professional Liability and Management Liability 11 17 28 16 Surety (20) (21) (46) (28) Warranty 7 (2) 20 (11) Other 2 1 (8) 5 Total pretax (favorable) unfavorable development $ — $ (5) $ (8) $ (9) The following table presents further detail of the development recorded for the Commercial segment. Periods ended September 30 Three Months Nine Months (In millions) 2024 2023 2024 2023 Pretax (favorable) unfavorable development: Commercial Auto $ 25 $ — $ 46 $ 11 General Liability 28 — 47 70 Workers' Compensation (57) (2) (106) (100) Property and Other 1 — 2 2 Total pretax (favorable) unfavorable development $ (3) $ (2) $ (11) $ (17) The following table presents further detail of the development recorded for the International segment. Periods ended September 30 Three Months Nine Months (In millions) 2024 2023 2024 2023 Pretax (favorable) unfavorable development: Commercial $ (13) $ — $ (7) $ (5) Specialty 11 — 2 22 Other — — — (2) Total pretax (favorable) unfavorable development $ (2) $ — $ (5) $ 15

Future Policy Benefits Reserv_2

Future Policy Benefits Reserves (Tables)	9 Months Ended
	Sep. 30, 2024
Insurance [Abstract]
Liability for Future Policy Benefit, Activity	The following table summarizes balances and changes in the LFPB. (In millions) 2024 2023 Present value of future net premiums Balance, January 1 $ 3,710 $ 3,993 Effect of changes in discount rate (125) (74) Balance, January 1, at original locked in discount rate 3,585 3,919 Effect of changes in cash flow assumptions (1) 111 28 Effect of actual variances from expected experience (1) (40) (112) Adjusted balance, January 1 3,656 3,835 Interest accrual 139 153 Net premiums: earned during period (317) (332) Balance, end of period at original locked in discount rate 3,478 3,656 Effect of changes in discount rate 147 (67) Balance, September 30 $ 3,625 $ 3,589 Present value of future benefits & expenses Balance, January 1 $ 17,669 $ 17,472 Effect of changes in discount rate (578) (125) Balance, January 1, at original locked in discount rate 17,091 17,347 Effect of changes in cash flow assumptions (1) 126 36 Effect of actual variances from expected experience (1) 33 (45) Adjusted balance, January 1 17,250 17,338 Interest accrual 693 723 Benefit & expense payments (883) (945) Balance, end of period at original locked in discount rate 17,060 17,116 Effect of changes in discount rate 612 (873) Balance, September 30 $ 17,672 $ 16,243 Net LFPB $ 14,047 $ 12,654 (1) As of September 30, 2024 and 2023 the re-measurement gain (loss) of $(88) million and $(75) million presented parenthetically on the Condensed Consolidated Statement of Operations is comprised of the effect of changes in cash flow assumptions and the effect of actual variances from expected experience. The following table presents earned premiums and interest expense associated with the Company’s long-term care business recognized on the Condensed Consolidated Statement of Operations. Periods ended September 30 Three Months Nine Months (In millions) 2024 2023 2024 2023 Earned premiums $ 110 $ 112 $ 329 $ 340 Interest expense 185 191 554 570 The following table presents undiscounted expected future benefit and expense payments, and undiscounted expected future gross premiums. As of September 30 (In millions) 2024 2023 Expected future benefit and expense payments $ 32,009 $ 33,217 Expected future gross premiums 5,305 5,557 The weighted average interest rates in the table below are calculated based on the rate used to discount all future cash flows. As of September 30 As of December 31 2024 2023 2023 Original locked in discount rate 5.20 % 5.24 % 5.22 % Upper-medium grade fixed income instrument discount rate 4.90 5.78 4.94

Benefit Plans (Tables)

Benefit Plans (Tables)	9 Months Ended
	Sep. 30, 2024
Retirement Benefits [Abstract]
Components of net periodic cost (benefit)	The components of net periodic pension cost (benefit) are presented in the following table. Periods ended September 30 Three Months Nine Months (In millions) 2024 2023 2024 2023 Net periodic pension cost (benefit) Interest cost on projected benefit obligation $ 21 $ 25 $ 65 $ 74 Expected return on plan assets (29) (29) (87) (89) Amortization of net actuarial loss 7 7 21 24 Pension settlement transaction loss (gain) 4 — 4 — Total net periodic pension cost (benefit) $ 3 $ 3 $ 3 $ 9 The following table indicates the line items in which the non-service cost (benefit) is presented in the Condensed Consolidated Statements of Operations. Periods ended September 30 Three Months Nine Months (In millions) 2024 2023 2024 2023 Non-Service Cost (Benefit): Insurance claims and policyholder's benefits $ 1 $ 1 $ 1 $ 2 Other operating expenses 2 2 2 7 Total net periodic pension cost (benefit) $ 3 $ 3 $ 3 $ 9

Accumulated Other Comprehensi_2

Accumulated Other Comprehensive Income (Loss) by Component (Tables)	9 Months Ended
	Sep. 30, 2024
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Accumulated Other Comprehensive Income (Loss) by Component	The tables below display the changes in Accumulated other comprehensive income (loss) by component. (In millions) Net unrealized gains (losses) on investments with an allowance for credit losses Net unrealized gains (losses) on other investments Pension and postretirement benefits Cumulative impact of changes in discount rates used to measure long duration contracts Cumulative foreign currency translation adjustment Total Balance as of July 1, 2024 $ (10) $ (2,074) $ (513) $ 255 $ (205) $ (2,547) Other comprehensive income (loss) before reclassifications (9) 1,254 — (623) 63 685 Amounts reclassified from accumulated other comprehensive income (loss) net of tax (expense) benefit of $2, $3, $3, $—, $— and $8 (6) (11) (8) — — (25) Other comprehensive income (loss) net of tax (expense) benefit of $1, $(340), $(3), $165, $— and $(177) (3) 1,265 8 (623) 63 710 Balance as of September 30, 2024 $ (13) $ (809) $ (505) $ (368) $ (142) $ (1,837) (In millions) Net unrealized gains (losses) on investments with an allowance for credit losses Net unrealized gains (losses) on other investments Pension and postretirement benefits Cumulative impact of changes in discount rates used to measure long duration contracts Cumulative foreign currency translation adjustment Total Balance as of July 1, 2023 $ (16) $ (2,481) $ (577) $ (181) $ (170) $ (3,425) Other comprehensive income (loss) before reclassifications (9) (1,105) — 818 (55) (351) Amounts reclassified from accumulated other comprehensive income (loss) net of tax (expense) benefit of $2, $6, $1, $—, $— and $9 (8) (21) (6) — — (35) Other comprehensive income (loss) net of tax (expense) benefit of $1, $289, $(1), $(217), $— and $72 (1) (1,084) 6 818 (55) (316) Balance as of September 30, 2023 $ (17) $ (3,565) $ (571) $ 637 $ (225) $ (3,741) (In millions) Net unrealized gains (losses) on investments with an allowance for credit losses Net unrealized gains (losses) on other investments Pension and postretirement benefits Cumulative impact of changes in discount rates used to measure long duration contracts Cumulative foreign currency translation adjustment Total Balance as of January 1, 2024 $ (12) $ (1,613) $ (525) $ (359) $ (163) $ (2,672) Other comprehensive income (loss) before reclassifications (14) 765 — (9) 21 763 Amounts reclassified from accumulated other comprehensive income (loss) net of tax (expense) benefit of $4, $10, $5, $—, $— and $19 (13) (39) (20) — — (72) Other comprehensive income (loss) net of tax (expense) benefit of $—, $(216), $(5), $2, $— and $(219) (1) 804 20 (9) 21 835 Balance as of September 30, 2024 $ (13) $ (809) $ (505) $ (368) $ (142) $ (1,837) (In millions) Net unrealized gains (losses) on investments with an allowance for credit losses Net unrealized gains (losses) on other investments Pension and postretirement benefits Cumulative impact of changes in discount rates used to measure long duration contracts Cumulative foreign currency translation adjustment Total Balance as of January 1, 2023, as previously reported $ (7) $ (2,738) $ (591) $ — $ (221) $ (3,557) Cumulative effect adjustment from changes in accounting guidance, net of tax (expense) benefit of $—, $—, $—, $11, $— and $11 — — — (41) — (41) Balance as of January 1, 2023 (7) (2,738) (591) (41) (221) (3,598) Other comprehensive income (loss) before reclassifications (25) (880) — 678 (4) (231) Amounts reclassified from accumulated other comprehensive income (loss) net of tax (expense) benefit of $4, $14, $5, $—, $— and $23 (15) (53) (20) — — (88) Other comprehensive income (loss) net of tax (expense) benefit of $3, $221, $(5), $(180), $— and $39 (10) (827) 20 678 (4) (143) Balance as of September 30, 2023 $ (17) $ (3,565) $ (571) $ 637 $ (225) $ (3,741)
Reclassification out of Accumulated Other Comprehensive Income	Amounts reclassified from Accumulated other comprehensive income (loss) shown above are reported in Net income (loss) as follows: Component of AOCI Condensed Consolidated Statements of Operations Line Item Affected by Reclassifications Net unrealized gains (losses) on investments with an allowance for credit losses and Net unrealized gains (losses) on other investments Net investment gains (losses) Pension and postretirement benefits Other operating expenses and Insurance claims and policyholders' benefits

Business Segments (Tables)

Business Segments (Tables)	9 Months Ended
	Sep. 30, 2024
Segment Reporting [Abstract]
Significant components of the Company's continuing operations and selected balance sheet items	The Company's results of operations and selected balance sheet items by segment are presented in the following tables. Three months ended September 30, 2024 Specialty Commercial International Life & Corporate (In millions) Eliminations Total Operating revenues Net earned premiums $ 848 $ 1,325 $ 311 $ 110 $ — $ (1) $ 2,593 Net investment income 157 183 32 240 14 — 626 Non-insurance warranty revenue 401 — — — — — 401 Other revenues 1 5 — — 3 (1) 8 Total operating revenues 1,407 1,513 343 350 17 (2) 3,628 Claims, benefits and expenses Net incurred claims and benefits 509 954 195 336 16 — 2,010 Policyholders’ dividends 2 7 — — — — 9 Amortization of deferred acquisition costs 188 209 60 — — — 457 Non-insurance warranty expense 387 — — — — — 387 Other insurance related expenses 90 158 44 30 — (1) 321 Other expenses 13 8 (8) 1 56 (1) 69 Total claims, benefits and expenses (1) 1,189 1,336 291 367 72 (2) 3,253 Core income (loss) before income tax 218 177 52 (17) (55) — 375 Income tax (expense) benefit on core income (loss) (47) (38) (16) 8 11 — (82) Core income (loss) $ 171 $ 139 $ 36 $ (9) $ (44) $ — 293 Net investment gains (losses) (10) Income tax (expense) benefit on net investment gains (losses) 3 Net investment gains (losses), after tax (7) Pension settlement transaction gains (losses) (4) Income tax (expense) benefit on pension settlement transaction gains (losses) 1 Pension settlement transaction gains (losses), after tax (3) Net income (loss) $ 283 (1) Excludes the impact of pension settlement transaction gains (losses). See Note H to the Condensed Consolidated Financial Statements for additional information. Three months ended September 30, 2023 Specialty Commercial International Life & Corporate (In millions) Eliminations Total Operating revenues Net earned premiums $ 829 $ 1,170 $ 296 $ 112 $ — $ (1) $ 2,406 Net investment income 136 156 26 216 19 — 553 Non-insurance warranty revenue 407 — — — — — 407 Other revenues — 9 (1) — 2 (2) 8 Total operating revenues 1,372 1,335 321 328 21 (3) 3,374 Claims, benefits and expenses Net incurred claims and benefits 480 807 178 343 10 — 1,818 Policyholders’ dividends 2 6 — — — — 8 Amortization of deferred acquisition costs 175 188 63 — — — 426 Non-insurance warranty expense 386 — — — — — 386 Other insurance related expenses 89 156 20 29 1 (1) 294 Other expenses 13 11 6 (1) 51 (2) 78 Total claims, benefits and expenses 1,145 1,168 267 371 62 (3) 3,010 Core income (loss) before income tax 227 167 54 (43) (41) — 364 Income tax (expense) benefit on core income (loss) (49) (34) (14) 14 8 — (75) Core income (loss) $ 178 $ 133 $ 40 $ (29) $ (33) $ — 289 Net investment gains (losses) (38) Income tax (expense) benefit on net investment gains (losses) 7 Net investment gains (losses), after tax (31) Net income (loss) $ 258 Nine months ended September 30, 2024 Specialty Commercial International Life & Corporate (In millions) Eliminations Total Operating revenues Net earned premiums $ 2,493 $ 3,774 $ 937 $ 329 $ — $ (1) $ 7,532 Net investment income 461 534 95 710 53 — 1,853 Non-insurance warranty revenue 1,212 — — — — — 1,212 Other revenues 1 23 — — 9 (7) 26 Total operating revenues 4,167 4,331 1,032 1,039 62 (8) 10,623 Claims, benefits and expenses Net incurred claims and benefits 1,478 2,628 568 973 35 — 5,682 Policyholders’ dividends 7 19 — — — — 26 Amortization of deferred acquisition costs 546 608 182 — — — 1,336 Non-insurance warranty expense 1,169 — — — — — 1,169 Other insurance related expenses 267 454 129 88 — (1) 937 Other expenses 41 33 (5) 2 173 (7) 237 Total claims, benefits and expenses (1) 3,508 3,742 874 1,063 208 (8) 9,387 Core income (loss) before income tax 659 589 158 (24) (146) — 1,236 Income tax (expense) benefit on core income (loss) (142) (125) (41) 19 27 — (262) Core income (loss) $ 517 $ 464 $ 117 $ (5) $ (119) $ — 974 Net investment gains (losses) (42) Income tax (expense) benefit on net investment gains (losses) 9 Net investment gains (losses), after tax (33) Pension settlement transaction gains (losses) (4) Income tax (expense) benefit on pension settlement transaction gains (losses) 1 Pension settlement transaction gains (losses), after tax (3) Net income (loss) $ 938 September 30, 2024 (In millions) Reinsurance receivables $ 1,509 $ 1,456 $ 533 $ 86 $ 2,236 $ — $ 5,820 Insurance receivables 986 2,149 375 3 1 — 3,514 Deferred acquisition costs 413 400 130 — — — 943 Goodwill 117 — 30 — — — 147 Deferred non-insurance warranty acquisition expense 3,571 — — — — — 3,571 Insurance reserves Claim and claim adjustment expenses 7,328 11,018 2,990 650 2,572 — 24,558 Unearned premiums 3,218 3,186 755 100 — — 7,259 Future policy benefits — — — 14,047 — — 14,047 Deferred non-insurance warranty revenue 4,594 — — — — — 4,594 (1) Excludes the impact of pension settlement transaction gains (losses). See Note H to the Condensed Consolidated Financial Statements for additional information. Nine months ended September 30, 2023 Specialty Commercial International Life & Corporate (In millions) Eliminations Total Operating revenues Net earned premiums $ 2,438 $ 3,336 $ 888 $ 340 $ — $ (1) $ 7,001 Net investment income 407 470 74 659 43 — 1,653 Non-insurance warranty revenue 1,221 — — — — — 1,221 Other revenues — 22 — — 7 (7) 22 Total operating revenues 4,066 3,828 962 999 50 (8) 9,897 Claims, benefits and expenses Net incurred claims and benefits 1,419 2,235 552 998 32 — 5,236 Policyholders’ dividends 5 17 — — — — 22 Amortization of deferred acquisition costs 508 532 168 — — — 1,208 Non-insurance warranty expense 1,154 — — — — — 1,154 Other insurance related expenses 269 456 102 89 2 (1) 917 Other expenses 39 27 2 — 136 (7) 197 Total claims, benefits and expenses 3,394 3,267 824 1,087 170 (8) 8,734 Core income (loss) before income tax 672 561 138 (88) (120) — 1,163 Income tax (expense) benefit on core income (loss) (146) (118) (36) 36 23 — (241) Core income (loss) $ 526 $ 443 $ 102 $ (52) $ (97) $ — 922 Net investment gains (losses) (105) Income tax (expense) benefit on net investment gains (losses) 21 Net investment gains (losses), after tax (84) Net income (loss) $ 838 December 31, 2023 (In millions) Reinsurance receivables $ 1,281 $ 1,218 $ 468 $ 93 $ 2,374 $ — $ 5,434 Insurance receivables 1,053 2,024 388 5 — — 3,470 Deferred acquisition costs 392 371 133 — — — 896 Goodwill 117 — 29 — — — 146 Deferred non-insurance warranty acquisition expense 3,661 — — — — — 3,661 Insurance reserves Claim and claim adjustment expenses 7,131 10,103 2,709 675 2,686 — 23,304 Unearned premiums 3,227 2,858 749 99 — — 6,933 Future policy benefits — — — 13,959 — — 13,959 Deferred non-insurance warranty revenue 4,694 — — — — — 4,694
Revenues by line of business	The following table presents operating revenues by line of business for each reportable segment. Periods ended September 30 Three Months Nine Months (In millions) 2024 2023 2024 2023 Specialty Management & Professional Liability $ 753 $ 723 $ 2,215 $ 2,146 Surety 202 189 580 540 Warranty & Alternative Risks 452 460 1,372 1,380 Specialty revenues 1,407 1,372 4,167 4,066 Commercial Middle Market 448 437 1,307 1,254 Construction 521 444 1,459 1,249 Small Business 161 160 472 470 Other Commercial 383 294 1,093 855 Commercial revenues 1,513 1,335 4,331 3,828 International Canada 99 98 296 287 Europe 150 139 440 401 Hardy 94 84 296 274 International revenues 343 321 1,032 962 Life & Group revenues 350 328 1,039 999 Corporate & Other revenues 17 21 62 50 Eliminations (2) (3) (8) (8) Total operating revenues 3,628 3,374 10,623 9,897 Net investment gains (losses) (10) (38) (42) (105) Total revenues $ 3,618 $ 3,336 $ 10,581 $ 9,792

General (Narrative) (Details)

General (Narrative) (Details)	Sep. 30, 2024
CNAF Consolidated | Loews
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Noncontrolling interest, ownership percentage by parent	92%

Earnings (Loss) Per Share Dat_2

Earnings (Loss) Per Share Data (Computations) (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Earnings Per Share [Abstract]
Net income	$ 283	$ 258	$ 938	$ 838
Basic
Weighted average shares outstanding (in shares)	271.3	271.2	271.5	271.2
Diluted
Weighted average shares outstanding (in shares)	271.3	271.2	271.5	271.2
Diluted effect of stock-based awards under compensation plans (in shares)	1.4	1.1	1.2	1
Total (in shares)	272.7	272.3	272.7	272.2
Earnings (loss) per share
Basic earnings (loss) per share (in usd per share)	$ 1.04	$ 0.95	$ 3.46	$ 3.09
Diluted earnings (loss) per share (in usd per share)	$ 1.04	$ 0.95	$ 3.44	$ 3.08

Earnings (Loss) Per Share Dat_3

Earnings (Loss) Per Share Data (Narrative) (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023
Earnings Per Share [Abstract]
Treasury stock, shares, acquired (in shares)	450,000	550,000
Purchase of treasury stock	$ 20	$ 24

Investments (Net investment inc

Investments (Net investment income) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Net Investment Income [Line Items]
Gross investment income	$ 647	$ 573	$ 1,916	$ 1,711
Investment expense	(21)	(20)	(63)	(58)
Net investment income	626	553	1,853	1,653
Fixed maturity securities
Net Investment Income [Line Items]
Gross investment income	517	491	1,530	1,443
Equity securities
Net Investment Income [Line Items]
Gross investment income	21	9	56	42
Limited partnership investments
Net Investment Income [Line Items]
Gross investment income	67	28	195	108
Mortgage loans
Net Investment Income [Line Items]
Gross investment income	14	15	43	43
Short-term investments
Net Investment Income [Line Items]
Gross investment income	20	23	68	51
Trading portfolio
Net Investment Income [Line Items]
Gross investment income	0	1	1	4
Other
Net Investment Income [Line Items]
Gross investment income	8	6	23	20
Common Stock
Net Investment Income [Line Items]
Net investment income (loss) recognized due to change in fair value of stock held	11	(3)	20	2
Non-redeemable preferred stock
Net Investment Income [Line Items]
Net investment income (loss) recognized due to change in fair value of stock held	$ 13	$ 2	$ 24	$ 2

Investments (Net realized inves

Investments (Net realized investment gains (losses)) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Fixed maturity securities:
Gross gains	$ 11	$ 12	$ 38	$ 55
Gross losses	(33)	(49)	(104)	(141)
Net investment gains (losses) on fixed maturity securities	(22)	(37)	(66)	(86)
Equity securities	13	2	25	(9)
Mortgage loans	0	(5)	0	(11)
Short-term investments and other	(1)	2	(1)	1
Net investment gains (losses)	$ (10)	$ (38)	$ (42)	$ (105)

Investments (Components of othe

Investments (Components of other-than-temporary impairment losses recognized in earnings) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Debt Securities, Available-for-sale [Line Items]
Impairment losses (gains) recognized in earnings	$ 12	$ 12	$ 32	$ 37
Corporate and other bonds
Debt Securities, Available-for-sale [Line Items]
Impairment losses (gains) recognized in earnings	8	8	23	25
Asset-backed
Debt Securities, Available-for-sale [Line Items]
Impairment losses (gains) recognized in earnings	$ 4	$ 4	$ 9	$ 12

Investments (Narrative) (Detail

Investments (Narrative) (Details) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024 USD ($) tranche	Sep. 30, 2023 USD ($)	Sep. 30, 2024 USD ($) tranche	Sep. 30, 2023 USD ($)	Dec. 31, 2023 USD ($)
Gain (Loss) on Securities [Line Items]
Mortgage loan losses due to changes in expected credit losses	$ 0	$ 5	$ 0	$ 11
Commitments to purchase or fund privately placed debt securities	1,645		1,645
Commitments to sell various privately placed debt securities	90		90
Fixed maturity securities	42,579		42,579		$ 40,425
Net investment income	626	553	1,853	1,653
Affiliated Entity
Gain (Loss) on Securities [Line Items]
Fixed maturity securities	52		52
Affiliated Entity | Maximum
Gain (Loss) on Securities [Line Items]
Net investment income	1
Mortgage loans
Gain (Loss) on Securities [Line Items]
Financing receivable, accrued interest, after allowance for credit loss	4		4
Fixed maturity securities
Gain (Loss) on Securities [Line Items]
Debt securities, available-for-sale, accrued interest, after allowance for credit loss	451	$ 430	451	$ 430	$ 435
Commercial mortgage-backed
Gain (Loss) on Securities [Line Items]
Amount of securitization	305		$ 305
Commercial mortgage-backed | Affiliated Entity
Gain (Loss) on Securities [Line Items]
Related party transaction, amounts of transaction	$ 50
Number of tranches | tranche	3		3

Investments (Summary of fixed m

Investments (Summary of fixed maturity and equity securities) (Details) - USD ($) $ in Millions	Sep. 30, 2024	Jun. 30, 2024	Dec. 31, 2023	Sep. 30, 2023	Jun. 30, 2023	Dec. 31, 2022
Fixed maturity securities available-for-sale:
Cost or Amortized Cost	$ 43,551		$ 42,414
Gross Unrealized Gains	1,282		1,022
Gross Unrealized Losses	2,236		2,995
Allowance for Credit Losses	18	$ 17	16	$ 18	$ 22	$ 1
Estimated Fair Value	42,579		40,425
Debt Securities, Trading, Unrealized Gain (Loss) [Abstract]
Total fixed maturity securities trading	0		0
Total fixed maturity securities trading	0		0
Debt securities, amortized cost	43,551		42,414
Total fixed maturity securities	42,579		40,425
Corporate and other bonds
Fixed maturity securities available-for-sale:
Cost or Amortized Cost	25,872		25,020
Gross Unrealized Gains	826		597
Gross Unrealized Losses	900		1,345
Allowance for Credit Losses	6	0	4	5	13	0
Estimated Fair Value	25,792		24,268
Debt Securities, Trading, Unrealized Gain (Loss) [Abstract]
Total fixed maturity securities	26,751		25,132
States, municipalities and political subdivisions
Fixed maturity securities available-for-sale:
Cost or Amortized Cost	7,406		7,713
Gross Unrealized Gains	359		382
Gross Unrealized Losses	617		703
Allowance for Credit Losses	0		0
Estimated Fair Value	7,148		7,392
Debt Securities, Trading, Unrealized Gain (Loss) [Abstract]
Total fixed maturity securities	7,148		7,392
Residential mortgage-backed
Fixed maturity securities available-for-sale:
Cost or Amortized Cost	3,684		3,411
Gross Unrealized Gains	32		16
Gross Unrealized Losses	362		425
Allowance for Credit Losses	0		0
Estimated Fair Value	3,354		3,002
Commercial mortgage-backed
Fixed maturity securities available-for-sale:
Cost or Amortized Cost	1,867		1,862
Gross Unrealized Gains	15		7
Gross Unrealized Losses	141		230
Allowance for Credit Losses	0		8
Estimated Fair Value	1,741		1,631
Other asset-backed
Fixed maturity securities available-for-sale:
Cost or Amortized Cost	3,743		3,515
Gross Unrealized Gains	40		13
Gross Unrealized Losses	186		256
Allowance for Credit Losses	12		4
Estimated Fair Value	3,585		3,268
Asset-backed
Fixed maturity securities available-for-sale:
Cost or Amortized Cost	9,294		8,788
Gross Unrealized Gains	87		36
Gross Unrealized Losses	689		911
Allowance for Credit Losses	12	$ 17	12	$ 13	$ 9	$ 1
Estimated Fair Value	8,680		7,901
Debt Securities, Trading, Unrealized Gain (Loss) [Abstract]
Total fixed maturity securities	8,680		7,901
U.S. Treasury and obligations of government-sponsored enterprises
Fixed maturity securities available-for-sale:
Cost or Amortized Cost	224		152
Gross Unrealized Gains	2		1
Gross Unrealized Losses	4		2
Allowance for Credit Losses	0		0
Estimated Fair Value	222		151
Foreign government
Fixed maturity securities available-for-sale:
Cost or Amortized Cost	755		741
Gross Unrealized Gains	8		6
Gross Unrealized Losses	26		34
Allowance for Credit Losses	0		0
Estimated Fair Value	$ 737		$ 713

Investments (Securities in a gr

Investments (Securities in a gross unrealized loss position) (Details) - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value, Less than 12 months	$ 2,623	$ 3,483
Gross Unrealized Losses, Less than 12 Months	47	74
Estimated Fair Value, 12 Months or Longer	19,777	22,248
Gross Unrealized Losses, 12 Months or Longer	2,189	2,921
Estimated Fair Value, Total	22,400	25,731
Gross Unrealized Losses, Total	2,236	2,995
Corporate and other bonds
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value, Less than 12 months	1,664	1,943
Gross Unrealized Losses, Less than 12 Months	31	37
Estimated Fair Value, 12 Months or Longer	11,240	13,406
Gross Unrealized Losses, 12 Months or Longer	869	1,308
Estimated Fair Value, Total	12,904	15,349
Gross Unrealized Losses, Total	900	1,345
States, municipalities and political subdivisions
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value, Less than 12 months	422	598
Gross Unrealized Losses, Less than 12 Months	7	18
Estimated Fair Value, 12 Months or Longer	3,155	3,104
Gross Unrealized Losses, 12 Months or Longer	610	685
Estimated Fair Value, Total	3,577	3,702
Gross Unrealized Losses, Total	617	703
Residential mortgage-backed
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value, Less than 12 months	130	233
Gross Unrealized Losses, Less than 12 Months	2	4
Estimated Fair Value, 12 Months or Longer	2,162	2,212
Gross Unrealized Losses, 12 Months or Longer	360	421
Estimated Fair Value, Total	2,292	2,445
Gross Unrealized Losses, Total	362	425
Commercial mortgage-backed
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value, Less than 12 months	112	200
Gross Unrealized Losses, Less than 12 Months	0	5
Estimated Fair Value, 12 Months or Longer	1,134	1,184
Gross Unrealized Losses, 12 Months or Longer	141	225
Estimated Fair Value, Total	1,246	1,384
Gross Unrealized Losses, Total	141	230
Other asset-backed
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value, Less than 12 months	151	392
Gross Unrealized Losses, Less than 12 Months	4	8
Estimated Fair Value, 12 Months or Longer	1,638	1,869
Gross Unrealized Losses, 12 Months or Longer	182	248
Estimated Fair Value, Total	1,789	2,261
Gross Unrealized Losses, Total	186	256
Asset-backed
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value, Less than 12 months	393	825
Gross Unrealized Losses, Less than 12 Months	6	17
Estimated Fair Value, 12 Months or Longer	4,934	5,265
Gross Unrealized Losses, 12 Months or Longer	683	894
Estimated Fair Value, Total	5,327	6,090
Gross Unrealized Losses, Total	689	911
U.S. Treasury and obligations of government-sponsored enterprises
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value, Less than 12 months	45	65
Gross Unrealized Losses, Less than 12 Months	2	1
Estimated Fair Value, 12 Months or Longer	45	23
Gross Unrealized Losses, 12 Months or Longer	2	1
Estimated Fair Value, Total	90	88
Gross Unrealized Losses, Total	4	2
Foreign government
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value, Less than 12 months	99	52
Gross Unrealized Losses, Less than 12 Months	1	1
Estimated Fair Value, 12 Months or Longer	403	450
Gross Unrealized Losses, 12 Months or Longer	25	33
Estimated Fair Value, Total	502	502
Gross Unrealized Losses, Total	$ 26	$ 34

Investments (Securities in a _2

Investments (Securities in a gross unrealized loss position by ratings) (Details) - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value	$ 22,400	$ 25,731
Gross Unrealized Losses	2,236	2,995
U.S. Government, Government agencies and Government-sponsored enterprises
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value	2,127	2,273
Gross Unrealized Losses	265	309
AAA
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value	1,277	1,524
Gross Unrealized Losses	221	261
AA
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value	3,641	3,817
Gross Unrealized Losses	547	658
A
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value	5,229	5,652
Gross Unrealized Losses	405	517
BBB
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value	9,243	11,523
Gross Unrealized Losses	689	1,095
Non-investment grade
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value	883	942
Gross Unrealized Losses	$ 109	$ 155

Investments (Allowance on avail

Investments (Allowance on available-for-sale securities with credit impairments and PCD assets activity) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Allowance for credit losses:
Balance, beginning of period	$ 17	$ 22	$ 16	$ 1
Additions to the allowance for credit losses:
Securities for which credit losses were not previously recorded	4	5	4	13
Available-for-sale securities accounted for as PCD assets	2	2	2	22
Reductions to the allowance for credit losses:
Securities sold during the period (realized)	0	0	4	6
Intent to sell or more likely than not will be required to sell the security before recovery of its amortized cost basis	0	0	1	3
Write-offs charged against the allowance	9	15	9	15
Recoveries of amounts previously written off	0	0	0	0
Additional increases or (decreases) to the allowance for credit losses on securities that had an allowance recorded in a previous period	4	4	10	6
Balance, end of period	18	18	18	18
Corporate and other bonds
Allowance for credit losses:
Balance, beginning of period	0	13	4	0
Additions to the allowance for credit losses:
Securities for which credit losses were not previously recorded	4	5	4	6
Available-for-sale securities accounted for as PCD assets	2	2	2	22
Reductions to the allowance for credit losses:
Securities sold during the period (realized)	0	0	3	6
Intent to sell or more likely than not will be required to sell the security before recovery of its amortized cost basis	0	0	1	3
Write-offs charged against the allowance	0	15	0	15
Recoveries of amounts previously written off	0	0	0	0
Additional increases or (decreases) to the allowance for credit losses on securities that had an allowance recorded in a previous period	0	0	0	1
Balance, end of period	6	5	6	5
Asset-backed
Allowance for credit losses:
Balance, beginning of period	17	9	12	1
Additions to the allowance for credit losses:
Securities for which credit losses were not previously recorded	0	0	0	7
Available-for-sale securities accounted for as PCD assets	0	0	0	0
Reductions to the allowance for credit losses:
Securities sold during the period (realized)	0	0	1	0
Intent to sell or more likely than not will be required to sell the security before recovery of its amortized cost basis	0	0	0	0
Write-offs charged against the allowance	9	0	9	0
Recoveries of amounts previously written off	0	0	0	0
Additional increases or (decreases) to the allowance for credit losses on securities that had an allowance recorded in a previous period	4	4	10	5
Balance, end of period	$ 12	$ 13	$ 12	$ 13

Investments (Contractual maturi

Investments (Contractual maturity) (Details) - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023
Investments [Abstract]
Due in one year or less, cost or amortized cost	$ 1,585	$ 1,121
Due after one year through five years, cost or amortized cost	11,948	11,563
Due after five years through ten years, cost or amortized cost	13,333	13,359
Due after ten years, cost or amortized cost	16,685	16,371
Cost or Amortized Cost	43,551	42,414
Due in one year or less, estimated fair value	1,565	1,091
Due after one year through five years, estimated fair value	11,800	11,180
Due after five years through ten years, estimated fair value	12,959	12,573
Due after ten years, estimated fair value	16,255	15,581
Estimated Fair Value	$ 42,579	$ 40,425

Investments (Credit quality ind

Investments (Credit quality indicator) (Details) - Mortgage loans $ in Millions	Sep. 30, 2024 USD ($)
Debt Securities, Available-for-sale [Line Items]
2024	$ 43
2023	126
2022	247
2021	76
2020	134
Prior	412
Total	1,038
DSCR ≥1.6x | LTV less than 55%
Debt Securities, Available-for-sale [Line Items]
2024	0
2023	33
2022	9
2021	2
2020	97
Prior	242
Total	383
DSCR ≥1.6x | LTV 55% to 65%
Debt Securities, Available-for-sale [Line Items]
2024	0
2023	0
2022	0
2021	5
2020	0
Prior	0
Total	5
DSCR ≥1.6x | LTV greater than 65%
Debt Securities, Available-for-sale [Line Items]
2024	0
2023	0
2022	30
2021	12
2020	0
Prior	0
Total	42
DSCR 1.2x - 1.6x | LTV less than 55%
Debt Securities, Available-for-sale [Line Items]
2024	0
2023	28
2022	5
2021	0
2020	13
Prior	50
Total	96
DSCR 1.2x - 1.6x | LTV 55% to 65%
Debt Securities, Available-for-sale [Line Items]
2024	43
2023	20
2022	36
2021	36
2020	4
Prior	31
Total	170
DSCR 1.2x - 1.6x | LTV greater than 65%
Debt Securities, Available-for-sale [Line Items]
2024	0
2023	13
2022	64
2021	0
2020	20
Prior	0
Total	97
DSCR ≤1.2 | LTV less than 55%
Debt Securities, Available-for-sale [Line Items]
2024	0
2023	0
2022	0
2021	0
2020	0
Prior	0
Total	0
DSCR ≤1.2 | LTV 55% to 65%
Debt Securities, Available-for-sale [Line Items]
2024	0
2023	32
2022	75
2021	0
2020	0
Prior	41
Total	148
DSCR ≤1.2 | LTV greater than 65%
Debt Securities, Available-for-sale [Line Items]
2024	0
2023	0
2022	28
2021	21
2020	0
Prior	48
Total	$ 97

Fair Value (Assets and liabilit

Fair Value (Assets and liabilities measured at fair value on a recurring basis) (Details) - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023
Fixed maturity securities:
Fixed maturity securities	$ 42,579	$ 40,425
Equity securities:
Equity securities	668	683
Short-term and other	1,721	2,008
Total assets	44,968	43,116
Other liabilities	0	1
Total liabilities	0	1
Corporate and other bonds
Fixed maturity securities:
Fixed maturity securities	26,751	25,132
States, municipalities and political subdivisions
Fixed maturity securities:
Fixed maturity securities	7,148	7,392
Asset-backed
Fixed maturity securities:
Fixed maturity securities	8,680	7,901
Common Stock
Equity securities:
Equity securities	183	191
Non-redeemable preferred stock
Equity securities:
Equity securities	485	492
Level 1
Fixed maturity securities:
Fixed maturity securities	225	161
Equity securities:
Equity securities	218	219
Short-term and other	1,691	1,976
Total assets	2,134	2,356
Other liabilities	0	0
Total liabilities	0	0
Level 1 | Corporate and other bonds
Fixed maturity securities:
Fixed maturity securities	225	161
Level 1 | States, municipalities and political subdivisions
Fixed maturity securities:
Fixed maturity securities	0	0
Level 1 | Asset-backed
Fixed maturity securities:
Fixed maturity securities	0	0
Level 1 | Common Stock
Equity securities:
Equity securities	171	167
Level 1 | Non-redeemable preferred stock
Equity securities:
Equity securities	47	52
Level 2
Fixed maturity securities:
Fixed maturity securities	40,157	38,274
Equity securities:
Equity securities	436	440
Short-term and other	30	32
Total assets	40,623	38,746
Other liabilities	0	1
Total liabilities	0	1
Level 2 | Corporate and other bonds
Fixed maturity securities:
Fixed maturity securities	25,289	23,926
Level 2 | States, municipalities and political subdivisions
Fixed maturity securities:
Fixed maturity securities	7,103	7,348
Level 2 | Asset-backed
Fixed maturity securities:
Fixed maturity securities	7,765	7,000
Level 2 | Common Stock
Equity securities:
Equity securities	0	0
Level 2 | Non-redeemable preferred stock
Equity securities:
Equity securities	436	440
Level 3
Fixed maturity securities:
Fixed maturity securities	2,197	1,990
Equity securities:
Equity securities	14	24
Short-term and other	0	0
Total assets	2,211	2,014
Other liabilities	0	0
Total liabilities	0	0
Level 3 | Corporate and other bonds
Fixed maturity securities:
Fixed maturity securities	1,237	1,045
Level 3 | States, municipalities and political subdivisions
Fixed maturity securities:
Fixed maturity securities	45	44
Level 3 | Asset-backed
Fixed maturity securities:
Fixed maturity securities	915	901
Level 3 | Common Stock
Equity securities:
Equity securities	12	24
Level 3 | Non-redeemable preferred stock
Equity securities:
Equity securities	$ 2	$ 0

Fair Value (Table of reconcilia

Fair Value (Table of reconciliation for assets and liabilities measured at fair value on a recurring basis using significant unobservable inputs) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, Beginning, Assets	$ 2,073	$ 1,923	$ 2,014	$ 1,676
Reported in Net investment gains (losses)	(3)	(4)	$ (10)	$ (5)
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]			Net investment losses	Net investment losses
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Asset, Gain (Loss), Statement of Other Comprehensive Income or Comprehensive Income [Extensible Enumeration]			Other comprehensive income (loss)	Other comprehensive income (loss)
Reported in Other comprehensive income (loss)	91	(66)	$ 54	$ (57)
Total realized and unrealized investment gains (losses)	92	(66)	65	(55)
Purchases	121	90	343	381
Sales	(10)	(2)	(43)	(4)
Settlements	(47)	(32)	(142)	(66)
Transfers into Level 3	0	0	11	34
Transfers out of Level 3	(18)	(7)	(37)	(60)
Balance, Ending, Assets	2,211	1,906	2,211	1,906
Unrealized gains (losses) on Level 3 assets and liabilities recognized in Net income (loss) in the period	0	(1)	2	(8)
Unrealized gains (losses) on Level 3 assets and liabilities recognized in Other comprehensive income (loss) in the period	89	(66)	49	(57)
Corporate and other bonds
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, Beginning, Assets	1,129	971	1,045	810
Reported in Net investment gains (losses)	0	0	0	0
Reported in Other comprehensive income (loss)	59	(36)	39	(27)
Total realized and unrealized investment gains (losses)	59	(36)	39	(27)
Purchases	83	29	229	178
Sales	(10)	0	(10)	0
Settlements	(24)	(19)	(77)	(27)
Transfers into Level 3	0	0	11	11
Transfers out of Level 3	0	0	0	0
Balance, Ending, Assets	1,237	945	1,237	945
Unrealized gains (losses) on Level 3 assets and liabilities recognized in Net income (loss) in the period	0	0	0	0
Unrealized gains (losses) on Level 3 assets and liabilities recognized in Other comprehensive income (loss) in the period	57	(36)	34	(27)
States, municipalities and political subdivisions
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, Beginning, Assets	43	43	44	43
Reported in Net investment gains (losses)	0	0	0	0
Reported in Other comprehensive income (loss)	2	(2)	1	(2)
Total realized and unrealized investment gains (losses)	2	(2)	1	(2)
Purchases	0	0	0	0
Sales	0	0	0	0
Settlements	0	0	0	0
Transfers into Level 3	0	0	0	0
Transfers out of Level 3	0	0	0	0
Balance, Ending, Assets	45	41	45	41
Unrealized gains (losses) on Level 3 assets and liabilities recognized in Net income (loss) in the period	0	0	0	0
Unrealized gains (losses) on Level 3 assets and liabilities recognized in Other comprehensive income (loss) in the period	2	(2)	1	(2)
Asset-backed
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, Beginning, Assets	887	883	901	788
Reported in Net investment gains (losses)	(3)	(4)	(10)	(5)
Reported in Other comprehensive income (loss)	30	(28)	14	(28)
Total realized and unrealized investment gains (losses)	31	(27)	19	(18)
Purchases	38	61	111	203
Sales	0	0	(14)	0
Settlements	(23)	(13)	(65)	(39)
Transfers into Level 3	0	0	0	23
Transfers out of Level 3	(18)	(7)	(37)	(60)
Balance, Ending, Assets	915	897	915	897
Unrealized gains (losses) on Level 3 assets and liabilities recognized in Net income (loss) in the period	0	0	0	0
Unrealized gains (losses) on Level 3 assets and liabilities recognized in Other comprehensive income (loss) in the period	30	(28)	14	(28)
Equity securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, Beginning, Assets	14	26	24	35
Reported in Net investment gains (losses)	0	0	0	0
Reported in Other comprehensive income (loss)	0	0	0	0
Total realized and unrealized investment gains (losses)	0	(1)	6	(8)
Purchases	0	0	3	0
Sales	0	(2)	(19)	(4)
Settlements	0	0	0	0
Transfers into Level 3	0	0	0	0
Transfers out of Level 3	0	0	0	0
Balance, Ending, Assets	14	23	14	23
Unrealized gains (losses) on Level 3 assets and liabilities recognized in Net income (loss) in the period	0	(1)	2	(8)
Unrealized gains (losses) on Level 3 assets and liabilities recognized in Other comprehensive income (loss) in the period	0	0	0	0
Reported in Net investment income
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Reported in Net investment income	4	4	21	7
Reported in Net investment income | Corporate and other bonds
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Reported in Net investment income	0	0	0	0
Reported in Net investment income | States, municipalities and political subdivisions
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Reported in Net investment income	0	0	0	0
Reported in Net investment income | Asset-backed
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Reported in Net investment income	4	5	15	15
Reported in Net investment income | Equity securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Reported in Net investment income	$ 0	$ (1)	$ 6	$ (8)

Fair Value (Narrative) (Details

Fair Value (Narrative) (Details) - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023
Fair Value Disclosures [Abstract]
Other invested assets overseas deposit	$ 77	$ 75

Fair Value (Quantitative inform

Fair Value (Quantitative information about significant unobservable inputs in the fair value measurement of level 3 assets) (Details) $ in Millions	Sep. 30, 2024 USD ($)	Dec. 31, 2023 USD ($)
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Estimated fair value	$ 44,968	$ 43,116
Fixed maturity securities | Discounted cash flow
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Estimated fair value	$ 1,713	$ 1,495
Credit spread | Discounted cash flow | Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Debt securities, available-for-sale, measurement Input	0.01	0.01
Credit spread | Discounted cash flow | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Debt securities, available-for-sale, measurement Input	0.06	0.07
Credit spread | Discounted cash flow | Weighted Average
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Debt securities, available-for-sale, measurement Input	0.02	0.02

Fair Value (Carrying amount and

Fair Value (Carrying amount and estimated fair value of financial instrument assets and liabilities which are not measured at fair value) (Details) - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023
Assets
Mortgage loans	$ 1,003	$ 1,035
Liabilities
Long-term debt	2,972	2,481
Carrying Amount
Assets
Mortgage loans	1,003	1,035
Liabilities
Short-term debt	0	550
Long-term debt	2,972	2,481
Estimated Fair Value
Assets
Mortgage loans	988	997
Liabilities
Short-term debt	0	546
Long-term debt	2,952	2,385
Level 1 | Estimated Fair Value
Assets
Mortgage loans	0	0
Liabilities
Short-term debt	0	0
Long-term debt	0	0
Level 2 | Estimated Fair Value
Assets
Mortgage loans	0	0
Liabilities
Short-term debt	0	546
Long-term debt	2,952	2,385
Level 3 | Estimated Fair Value
Assets
Mortgage loans	988	997
Liabilities
Short-term debt	0	0
Long-term debt	$ 0	$ 0

Claim and Claim Adjustment Ex_3

Claim and Claim Adjustment Expense Reserves (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023	Dec. 31, 2010
Liability for Claims and Claims Adjustment Expense [Line Items]
Unusual or infrequent item, or both, net of insurance proceeds	$ 143	$ 94	$ 313	$ 214
Retroactive reinsurance benefit recognized	11	15	36	38
Cumulative amounts ceded under AEP Loss Portfolio Transfer	3,600		3,600		$ 3,600
Total pretax (favorable) unfavorable development	17	13	33	44
Hurricane Helene
Liability for Claims and Claims Adjustment Expense [Line Items]
Unusual or infrequent item, or both, net of insurance proceeds			55
Corporate & Other
Liability for Claims and Claims Adjustment Expense [Line Items]
Total pretax (favorable) unfavorable development	22	$ 20	57	$ 55
Asbestos and Environmental Reserves
Liability for Claims and Claims Adjustment Expense [Line Items]
Net A&EP claim and allocated claim adjustment expense reserves ceded to NICO						$ 1,600
Aggregate limit under A&EP Loss Portfolio Transfer						4,000
A&EP claim and allocated claim adjustment expense reserves ceded under existing third party reinsurance contracts transferred to NICO under A&EP Loss Portfolio Transfer						1,200
Reinsurance premium paid to NICO under A&EP Loss Portfolio Transfer						2,000
Net reinsurance receivables transferred to NICO under A&EP Loss Portfolio Transfer						215
Total consideration paid to NICO under AEP Loss Portfolio Transfer						$ 2,200
Deferred reinsurance benefit yet to be recognized	382		382		$ 417
Fair value of collateral trust account established by NICO under A&EP Loss Portfolio Transfer	$ 2,300		$ 2,300

Claim and Claim Adjustment Ex_4

Claim and Claim Adjustment Expense Reserves (Reconciliation of claim and claim adjustment expense reserves) (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023
Reserves, beginning of year:
Gross	$ 23,304	$ 22,120
Ceded	5,141	5,191
Net reserves, beginning of year	18,163	16,929
Net incurred claim and claim adjustment expenses:
Provision for insured events of current year	4,706	4,221
Increase (decrease) in provision for insured events of prior years	26	43
Amortization of discount	30	33
Total net incurred	4,762	4,297
Net payments attributable to:
Current year events	(655)	(588)
Prior year events	(3,189)	(2,953)
Total net payments	(3,844)	(3,541)
Foreign currency translation adjustment and other	35	(30)
Net reserves, end of period	19,116	17,655
Ceded reserves, end of period	5,442	5,181
Gross reserves, end of period	$ 24,558	$ 22,836

Claim and Claim Adjustment Ex_5

Claim and Claim Adjustment Expense Reserves (Net prior year development) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Segment Reporting Information [Line Items]
Total pretax (favorable) unfavorable development	$ 17	$ 13	$ 33	$ 44
Specialty
Segment Reporting Information [Line Items]
Total pretax (favorable) unfavorable development	0	(5)	(8)	(9)
Commercial
Segment Reporting Information [Line Items]
Total pretax (favorable) unfavorable development	(3)	(2)	(11)	(17)
International
Segment Reporting Information [Line Items]
Total pretax (favorable) unfavorable development	(2)	0	(5)	15
Corporate & Other
Segment Reporting Information [Line Items]
Total pretax (favorable) unfavorable development	$ 22	$ 20	$ 57	$ 55

Claim and Claim Adjustment Ex_6

Claim and Claim Adjustment Expense Reserves (Specialty - Net prior year claim and allocated claim adjustment expense reserve development) (Details) - Specialty - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Liability for Claims and Claims Adjustment Expense [Line Items]
Medical Professional Liability	$ 0	$ 0	$ (2)	$ 9
Other Professional Liability and Management Liability	11	17	28	16
Surety	(20)	(21)	(46)	(28)
Warranty	7	(2)	20	(11)
Other	2	1	(8)	5
Total pretax (favorable) unfavorable development	$ 0	$ (5)	$ (8)	$ (9)

Claim and Claim Adjustment Ex_7

Claim and Claim Adjustment Expense Reserves (Commercial - Net prior year claim and allocated claim adjustment expense reserve development) (Details) - Commercial - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Liability for Claims and Claims Adjustment Expense [Line Items]
Commercial	$ 25	$ 0	$ 46	$ 11
General Liability	28	0	47	70
Workers' Compensation	(57)	(2)	(106)	(100)
Property and Other	1	0	2	2
Total pretax (favorable) unfavorable development	$ (3)	$ (2)	$ (11)	$ (17)

Claim and Claim Adjustment Ex_8

Claim and Claim Adjustment Expense Reserves (International - Net prior year claim and allocated claim adjustment expense reserve development) (Details) - International - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Liability for Claims and Claims Adjustment Expense [Line Items]
Commercial	$ (13)	$ 0	$ (7)	$ (5)
Specialty	11	0	2	22
Other	0	0	0	(2)
Total pretax (favorable) unfavorable development	$ (2)	$ 0	$ (5)	$ 15

Future Policy Benefits Reserv_3

Future Policy Benefits Reserves - Summary of Balances and Changes (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023	Dec. 31, 2022
Present value of future net premiums
Balance, January 1			$ 3,710	$ 3,993
Effect of changes in discount rate	$ (147)	$ 67	(147)	67	$ (125)	$ (74)
Balance, January 1, at original locked in discount rate			3,585	3,919
Effect of changes in cash flow assumptions					111	28
Expect of actual variances from expected experience					(40)	(112)
Adjusted balance, January 1					3,656	3,835
Interest accrual			139	153
Net premiums: earned during period			(317)	(332)
Balance, end of period at original locked in discount rate	3,478	3,656	3,478	3,656
Balance, September 30	3,625	3,589	3,625	3,589
Present value of future benefits & expenses
Balance, January 1			17,669	17,472
Effect of changes in discount rate	612	(873)	612	(873)	578	125
Balance, January 1, at original locked in discount rate			17,091	17,347
Effect of change in cash flow assumptions					126	36
Effect of actual variances from expected experience					33	(45)
Adjusted balance, January 1					17,250	$ 17,338
Interest accrual			693	723
Benefit & expense payments			(883)	(945)
Balance, end of period at original locked in discount rate	17,060	17,116	17,060	17,116
Balance, September 30	17,672	16,243	17,672	16,243
Net LFPB	14,047	12,654	14,047	12,654	$ 13,959
Insurance claims and policyholders benefits, including policyholders' dividends, remeasurement impact	$ (48)	$ (41)	$ (88)	$ (75)

Future Policy Benefits Reserv_4

Future Policy Benefits Reserves - Earned Premiums and Interest Expense (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Insurance [Abstract]
Earned premiums	$ 110	$ 112	$ 329	$ 340
Interest expense	$ 185	$ 191	$ 554	$ 570

Future Policy Benefits Reserv_5

Future Policy Benefits Reserves - Undiscounted Expected Future Benefit and Expense Payments and Undiscounted Expected Future Gross Premiums (Details) - USD ($) $ in Millions	Sep. 30, 2024	Sep. 30, 2023
Insurance [Abstract]
Expected future benefit and expense payments	$ 32,009	$ 33,217
Expected future gross premiums	$ 5,305	$ 5,557

Future Policy Benefits Reserv_6

Future Policy Benefits Reserves - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Insurance [Abstract]
Liability for unpaid claims and claims adjustment expense, long term care policies, period increase (decrease)	$ 15	$ 8
Liability for future policy benefit, expected future gross premium, discounted, before reinsurance	$ 3,792	$ 3,711	$ 3,792	$ 3,711
Liability for future policy benefit, weighted-average duration	11 years	12 years	11 years	12 years
Liability future policy benefit, losses recognized in current period	$ 84	$ 109	$ 128	$ 152
Liability future policy benefit, losses recognized in prior period	$ 20	$ 26	$ 28	$ 37

Future Policy Benefits Reserv_7

Future Policy Benefits Reserves - Weighted Average Interest Rates (Details)	Sep. 30, 2024	Dec. 31, 2023	Sep. 30, 2023
Insurance [Abstract]
Original locked in discount rate	5.20%	5.22%	5.24%
Upper-medium grade fixed income instrument discount rate	4.90%	4.94%	5.78%

Legal Proceedings, Contingenc_2

Legal Proceedings, Contingencies and Guarantees (Narrative) (Details) $ in Billions	Sep. 30, 2024 USD ($)
Guarantee Obligations
Legal Proceedings, Commitments and Contingencies, and Guarantees [Line Items]
Guarantor obligations, maximum exposure, undiscounted	$ 1.4

Benefit Plans (Components of Ne

Benefit Plans (Components of Net Periodic Cost (Benefit)) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Defined Benefit Plan Disclosure [Line Items]
Pension settlement transaction loss (gain)	$ 4		$ 4
Pension settlement transaction gains (losses), after tax	3		3
Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Interest cost on projected benefit obligation	21	$ 25	65	$ 74
Expected return on plan assets	(29)	(29)	(87)	(89)
Amortization of net actuarial loss	7	7	21	24
Pension settlement transaction loss (gain)	4	0	4	0
Total net periodic pension cost (benefit)	$ 3	$ 3	$ 3	$ 9

Benefit Plans (Schedule of Non-

Benefit Plans (Schedule of Non-Service Cost (Benefit) Presented in the Consolidated Statement of Operations) (Details) - Pension Plan - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net periodic defined benefits expense (reversal of expense), excluding service cost component	$ 3	$ 3	$ 3	$ 9
Insurance claims and policyholder's benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net periodic defined benefits expense (reversal of expense), excluding service cost component	1	1	1	2
Other operating expenses
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net periodic defined benefits expense (reversal of expense), excluding service cost component	$ 2	$ 2	$ 2	$ 7

Accumulated Other Comprehensi_3

Accumulated Other Comprehensive Income (Loss) by Component (Schedule of Accumulated Other Comprehensive Income (Loss) by Component) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Jun. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Total stockholder's equity at beginning of period				$ 9,893
Other comprehensive income (loss) before reclassifications	$ 685	$ (351)		763	$ (231)
Amounts reclassified from accumulated other comprehensive income (loss) net of tax	(25)	(35)		(72)	(88)
Other comprehensive income (loss) after tax (expense) benefit	710	(316)		835	(143)
Total stockholder's equity at end of period	10,758	8,563		10,758	8,563
Cumulative effect adjustments from changes in accounting guidance, tax			$ 11
Reclassification from AOCI, tax	8	9		19	23
Tax (expense) benefit on other comprehensive income (loss)	(177)	72		(219)	39
Accumulated other comprehensive income (loss)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Total stockholder's equity at beginning of period	(2,547)	(3,425)	(3,598)	(2,672)	(3,598)
Total stockholder's equity at end of period	(1,837)	(3,741)	(3,425)	(1,837)	(3,741)
Accumulated other comprehensive income (loss) | Previously Reported
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Total stockholder's equity at beginning of period	(2,547)	(3,425)	(3,557)	(2,672)	(3,557)
Total stockholder's equity at end of period			(3,425)
Accumulated other comprehensive income (loss) | Revision of Prior Period, Accounting Standards Update, Adjustment
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Total stockholder's equity at beginning of period	0	0	(41)	0	(41)
Total stockholder's equity at end of period			0
Net unrealized gains (losses) on investments | Net unrealized gains (losses) on investments with an allowance for credit losses
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Total stockholder's equity at beginning of period	(10)	(16)	(7)	(12)	(7)
Other comprehensive income (loss) before reclassifications	(9)	(9)		(14)	(25)
Amounts reclassified from accumulated other comprehensive income (loss) net of tax	(6)	(8)		(13)	(15)
Other comprehensive income (loss) after tax (expense) benefit	(3)	(1)		(1)	(10)
Total stockholder's equity at end of period	(13)	(17)	(16)	(13)	(17)
Cumulative effect adjustments from changes in accounting guidance, tax			0
Reclassification from AOCI, tax	2	2		4	4
Tax (expense) benefit on other comprehensive income (loss)	1	1		0	3
Net unrealized gains (losses) on investments | Net unrealized gains (losses) on investments with an allowance for credit losses | Previously Reported
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Total stockholder's equity at beginning of period			(7)		(7)
Net unrealized gains (losses) on investments | Net unrealized gains (losses) on investments with an allowance for credit losses | Revision of Prior Period, Accounting Standards Update, Adjustment
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Total stockholder's equity at beginning of period			0		0
Net unrealized gains (losses) on investments | Net unrealized gains and losses on other investments
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Total stockholder's equity at beginning of period	(2,074)	(2,481)	(2,738)	(1,613)	(2,738)
Other comprehensive income (loss) before reclassifications	1,254	(1,105)		765	(880)
Amounts reclassified from accumulated other comprehensive income (loss) net of tax	(11)	(21)		(39)	(53)
Other comprehensive income (loss) after tax (expense) benefit	1,265	(1,084)		804	(827)
Total stockholder's equity at end of period	(809)	(3,565)	(2,481)	(809)	(3,565)
Cumulative effect adjustments from changes in accounting guidance, tax			0
Reclassification from AOCI, tax	3	6		10	14
Tax (expense) benefit on other comprehensive income (loss)	(340)	289		(216)	221
Net unrealized gains (losses) on investments | Net unrealized gains and losses on other investments | Previously Reported
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Total stockholder's equity at beginning of period			(2,738)		(2,738)
Net unrealized gains (losses) on investments | Net unrealized gains and losses on other investments | Revision of Prior Period, Accounting Standards Update, Adjustment
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Total stockholder's equity at beginning of period			0		0
Pension and postretirement benefits
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Total stockholder's equity at beginning of period	(513)	(577)	(591)	(525)	(591)
Other comprehensive income (loss) before reclassifications	0	0		0	0
Amounts reclassified from accumulated other comprehensive income (loss) net of tax	(8)	(6)		(20)	(20)
Other comprehensive income (loss) after tax (expense) benefit	8	6		20	20
Total stockholder's equity at end of period	(505)	(571)	(577)	(505)	(571)
Cumulative effect adjustments from changes in accounting guidance, tax			0
Reclassification from AOCI, tax	3	1		5	5
Tax (expense) benefit on other comprehensive income (loss)	(3)	(1)		(5)	(5)
Pension and postretirement benefits | Previously Reported
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Total stockholder's equity at beginning of period			(591)		(591)
Pension and postretirement benefits | Revision of Prior Period, Accounting Standards Update, Adjustment
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Total stockholder's equity at beginning of period			0		0
Cumulative impact of changes in discount rates used to measure long duration contracts
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Total stockholder's equity at beginning of period	255	(181)	(41)	(359)	(41)
Other comprehensive income (loss) before reclassifications	(623)	818		(9)	678
Amounts reclassified from accumulated other comprehensive income (loss) net of tax	0	0		0	0
Other comprehensive income (loss) after tax (expense) benefit	(623)	818		(9)	678
Total stockholder's equity at end of period	(368)	637	(181)	(368)	637
Cumulative effect adjustments from changes in accounting guidance, tax			11
Reclassification from AOCI, tax	0	0		0	0
Tax (expense) benefit on other comprehensive income (loss)	165	(217)		2	(180)
Cumulative impact of changes in discount rates used to measure long duration contracts | Previously Reported
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Total stockholder's equity at beginning of period			0		0
Cumulative impact of changes in discount rates used to measure long duration contracts | Revision of Prior Period, Accounting Standards Update, Adjustment
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Total stockholder's equity at beginning of period			(41)		(41)
Cumulative foreign currency translation adjustment
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Total stockholder's equity at beginning of period	(205)	(170)	(221)	(163)	(221)
Other comprehensive income (loss) before reclassifications	63	(55)		21	(4)
Amounts reclassified from accumulated other comprehensive income (loss) net of tax	0	0		0	0
Other comprehensive income (loss) after tax (expense) benefit	63	(55)		21	(4)
Total stockholder's equity at end of period	(142)	(225)	(170)	(142)	(225)
Cumulative effect adjustments from changes in accounting guidance, tax			0
Reclassification from AOCI, tax	0	0		0	0
Tax (expense) benefit on other comprehensive income (loss)	$ 0	$ 0		$ 0	0
Cumulative foreign currency translation adjustment | Previously Reported
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Total stockholder's equity at beginning of period			(221)		(221)
Cumulative foreign currency translation adjustment | Revision of Prior Period, Accounting Standards Update, Adjustment
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Total stockholder's equity at beginning of period			$ 0		$ 0

Business Segments (Narrative) (

Business Segments (Narrative) (Details)	9 Months Ended
	Sep. 30, 2024 segment
Core Segments - Specialty, Commercial and International
Segment Reporting Information [Line Items]
Number of operating segments	3
Non-Core Segments - Life & Group and Corporate & Other
Segment Reporting Information [Line Items]
Number of operating segments	2

Business Segments (Income State

Business Segments (Income Statement Information) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Operating revenues
Net earned premiums	$ 2,593	$ 2,406	$ 7,532	$ 7,001
Net investment income	626	553	1,853	1,653
Non-insurance warranty revenue	401	407	1,212	1,221
Other revenues	8	8	26	22
Total operating revenues	3,628	3,374	10,623	9,897
Claims, Benefits and Expenses
Net incurred claims and benefits	2,010	1,818	5,682	5,236
Policyholders’ dividends	9	8	26	22
Amortization of deferred acquisition costs	457	426	1,336	1,208
Non-insurance warranty expense	387	386	1,169	1,154
Other insurance related expenses	321	294	937	917
Other expenses	69	78	237	197
Total claims, benefits and expenses	3,257	3,010	9,391	8,734
Total claims, benefits and expenses	3,253		9,387
Core income (loss) before income tax	375	364	1,236	1,163
Income tax (expense) benefit on core income (loss)	(82)	(75)	(262)	(241)
Core income (loss)	293	289	974	922
Net investment gains (losses)	(10)	(38)	(42)	(105)
Income tax (expense) benefit on net investment gains (losses)	3	7	9	21
Net investment gains (losses), after tax	(7)	(31)	(33)	(84)
Pension settlement transaction gains (losses)	(4)		(4)
Income tax (expense) benefit on pension settlement transaction gains (losses)	1		1
Pension settlement transaction gains (losses), after tax	(3)		(3)
Net income (loss)	283	258	938	838
Operating Segments | Specialty
Operating revenues
Net earned premiums	848	829	2,493	2,438
Net investment income	157	136	461	407
Non-insurance warranty revenue	401	407	1,212	1,221
Other revenues	1	0	1	0
Total operating revenues	1,407	1,372	4,167	4,066
Claims, Benefits and Expenses
Net incurred claims and benefits	509	480	1,478	1,419
Policyholders’ dividends	2	2	7	5
Amortization of deferred acquisition costs	188	175	546	508
Non-insurance warranty expense	387	386	1,169	1,154
Other insurance related expenses	90	89	267	269
Other expenses	13	13	41	39
Total claims, benefits and expenses		1,145		3,394
Total claims, benefits and expenses	1,189		3,508
Core income (loss) before income tax	218	227	659	672
Income tax (expense) benefit on core income (loss)	(47)	(49)	(142)	(146)
Core income (loss)	171	178	517	526
Operating Segments | Commercial
Operating revenues
Net earned premiums	1,325	1,170	3,774	3,336
Net investment income	183	156	534	470
Non-insurance warranty revenue	0	0	0	0
Other revenues	5	9	23	22
Total operating revenues	1,513	1,335	4,331	3,828
Claims, Benefits and Expenses
Net incurred claims and benefits	954	807	2,628	2,235
Policyholders’ dividends	7	6	19	17
Amortization of deferred acquisition costs	209	188	608	532
Non-insurance warranty expense	0	0	0	0
Other insurance related expenses	158	156	454	456
Other expenses	8	11	33	27
Total claims, benefits and expenses		1,168		3,267
Total claims, benefits and expenses	1,336		3,742
Core income (loss) before income tax	177	167	589	561
Income tax (expense) benefit on core income (loss)	(38)	(34)	(125)	(118)
Core income (loss)	139	133	464	443
Operating Segments | International
Operating revenues
Net earned premiums	311	296	937	888
Net investment income	32	26	95	74
Non-insurance warranty revenue	0	0	0	0
Other revenues	0	(1)	0	0
Total operating revenues	343	321	1,032	962
Claims, Benefits and Expenses
Net incurred claims and benefits	195	178	568	552
Policyholders’ dividends	0	0	0	0
Amortization of deferred acquisition costs	60	63	182	168
Non-insurance warranty expense	0	0	0	0
Other insurance related expenses	44	20	129	102
Other expenses	(8)	6	(5)	2
Total claims, benefits and expenses		267		824
Total claims, benefits and expenses	291		874
Core income (loss) before income tax	52	54	158	138
Income tax (expense) benefit on core income (loss)	(16)	(14)	(41)	(36)
Core income (loss)	36	40	117	102
Operating Segments | Life & Group
Operating revenues
Net earned premiums	110	112	329	340
Net investment income	240	216	710	659
Non-insurance warranty revenue	0	0	0	0
Other revenues	0	0	0	0
Total operating revenues	350	328	1,039	999
Claims, Benefits and Expenses
Net incurred claims and benefits	336	343	973	998
Policyholders’ dividends	0	0	0	0
Amortization of deferred acquisition costs	0	0	0	0
Non-insurance warranty expense	0	0	0	0
Other insurance related expenses	30	29	88	89
Other expenses	1	(1)	2	0
Total claims, benefits and expenses		371		1,087
Total claims, benefits and expenses	367		1,063
Core income (loss) before income tax	(17)	(43)	(24)	(88)
Income tax (expense) benefit on core income (loss)	8	14	19	36
Core income (loss)	(9)	(29)	(5)	(52)
Operating Segments | Corporate & Other
Operating revenues
Net earned premiums	0	0	0	0
Net investment income	14	19	53	43
Non-insurance warranty revenue	0	0	0	0
Other revenues	3	2	9	7
Total operating revenues	17	21	62	50
Claims, Benefits and Expenses
Net incurred claims and benefits	16	10	35	32
Policyholders’ dividends	0	0	0	0
Amortization of deferred acquisition costs	0	0	0	0
Non-insurance warranty expense	0	0	0	0
Other insurance related expenses	0	1	0	2
Other expenses	56	51	173	136
Total claims, benefits and expenses		62		170
Total claims, benefits and expenses	72		208
Core income (loss) before income tax	(55)	(41)	(146)	(120)
Income tax (expense) benefit on core income (loss)	11	8	27	23
Core income (loss)	(44)	(33)	(119)	(97)
Eliminations
Operating revenues
Net earned premiums	(1)	(1)	(1)	(1)
Net investment income	0	0	0	0
Non-insurance warranty revenue	0	0	0	0
Other revenues	(1)	(2)	(7)	(7)
Total operating revenues	(2)	(3)	(8)	(8)
Claims, Benefits and Expenses
Net incurred claims and benefits	0	0	0	0
Policyholders’ dividends	0	0	0	0
Amortization of deferred acquisition costs	0	0	0	0
Non-insurance warranty expense	0	0	0	0
Other insurance related expenses	(1)	(1)	(1)	(1)
Other expenses	(1)	(2)	(7)	(7)
Total claims, benefits and expenses		(3)		(8)
Total claims, benefits and expenses	(2)		(8)
Core income (loss) before income tax	0	0	0	0
Income tax (expense) benefit on core income (loss)	0	0	0	0
Core income (loss)	$ 0	$ 0	$ 0	$ 0

Business Segments (Balance Shee

Business Segments (Balance Sheet Information) (Details) - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023	Sep. 30, 2023
Segment Reporting Information [Line Items]
Reinsurance receivables	$ 5,820	$ 5,434
Insurance receivables	3,514	3,470
Deferred acquisition costs	943	896
Goodwill	147	146
Deferred non-insurance warranty acquisition expense	3,571	3,661
Insurance reserves
Claim and claim adjustment expenses	24,558	23,304
Unearned premiums	7,259	6,933
Future policy benefits	14,047	13,959	$ 12,654
Deferred non-insurance warranty revenue	4,594	4,694
Operating Segments | Specialty
Segment Reporting Information [Line Items]
Reinsurance receivables	1,509	1,281
Insurance receivables	986	1,053
Deferred acquisition costs	413	392
Goodwill	117	117
Deferred non-insurance warranty acquisition expense	3,571	3,661
Insurance reserves
Claim and claim adjustment expenses	7,328	7,131
Unearned premiums	3,218	3,227
Future policy benefits	0	0
Deferred non-insurance warranty revenue	4,594	4,694
Operating Segments | Commercial
Segment Reporting Information [Line Items]
Reinsurance receivables	1,456	1,218
Insurance receivables	2,149	2,024
Deferred acquisition costs	400	371
Goodwill	0	0
Deferred non-insurance warranty acquisition expense	0	0
Insurance reserves
Claim and claim adjustment expenses	11,018	10,103
Unearned premiums	3,186	2,858
Future policy benefits	0	0
Deferred non-insurance warranty revenue	0	0
Operating Segments | International
Segment Reporting Information [Line Items]
Reinsurance receivables	533	468
Insurance receivables	375	388
Deferred acquisition costs	130	133
Goodwill	30	29
Deferred non-insurance warranty acquisition expense	0	0
Insurance reserves
Claim and claim adjustment expenses	2,990	2,709
Unearned premiums	755	749
Future policy benefits	0	0
Deferred non-insurance warranty revenue	0	0
Operating Segments | Life & Group
Segment Reporting Information [Line Items]
Reinsurance receivables	86	93
Insurance receivables	3	5
Deferred acquisition costs	0	0
Goodwill	0	0
Deferred non-insurance warranty acquisition expense	0	0
Insurance reserves
Claim and claim adjustment expenses	650	675
Unearned premiums	100	99
Future policy benefits	14,047	13,959
Deferred non-insurance warranty revenue	0	0
Operating Segments | Corporate & Other
Segment Reporting Information [Line Items]
Reinsurance receivables	2,236	2,374
Insurance receivables	1	0
Deferred acquisition costs	0	0
Goodwill	0	0
Deferred non-insurance warranty acquisition expense	0	0
Insurance reserves
Claim and claim adjustment expenses	2,572	2,686
Unearned premiums	0	0
Future policy benefits	0	0
Deferred non-insurance warranty revenue	0	0
Eliminations
Segment Reporting Information [Line Items]
Reinsurance receivables	0	0
Insurance receivables	0	0
Deferred acquisition costs	0	0
Goodwill	0	0
Deferred non-insurance warranty acquisition expense	0	0
Insurance reserves
Claim and claim adjustment expenses	0	0
Unearned premiums	0	0
Future policy benefits	0	0
Deferred non-insurance warranty revenue	$ 0	$ 0

Business Segments (Revenues by

Business Segments (Revenues by Line of Business) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Total revenues	$ 3,618	$ 3,336	$ 10,581	$ 9,792
Total operating revenues	3,628	3,374	10,623	9,897
Net investment gains (losses)	(10)	(38)	(42)	(105)
Operating Segments | Specialty
Total revenues	1,407	1,372	4,167	4,066
Operating Segments | Commercial
Total revenues	1,513	1,335	4,331	3,828
Operating Segments | International
Total revenues	343	321	1,032	962
Operating Segments | Life & Group
Total revenues	350	328	1,039	999
Operating Segments | Corporate & Other
Total revenues	17	21	62	50
Eliminations
Total revenues	(2)	(3)	(8)	(8)
Management & Professional Liability | Operating Segments | Specialty
Total revenues	753	723	2,215	2,146
Surety | Operating Segments | Specialty
Total revenues	202	189	580	540
Warranty & Alternative Risks | Operating Segments | Specialty
Total revenues	452	460	1,372	1,380
Middle Market | Operating Segments | Commercial
Total revenues	448	437	1,307	1,254
Construction | Operating Segments | Commercial
Total revenues	521	444	1,459	1,249
Small Business | Operating Segments | Commercial
Total revenues	161	160	472	470
Other Commercial | Operating Segments | Commercial
Total revenues	383	294	1,093	855
Canada | Operating Segments | International
Total revenues	99	98	296	287
Europe | Operating Segments | International
Total revenues	150	139	440	401
Hardy | Operating Segments | International
Total revenues	$ 94	$ 84	$ 296	$ 274

Non-Insurance Revenues from C_2

Non-Insurance Revenues from Contracts with Customers (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Revenue from Contract with Customer [Abstract]
Deferred non-insurance warranty revenue	$ 4,594		$ 4,594		$ 4,694
Contract with customer, liability, revenue recognized	$ 300	$ 200	$ 1,100	$ 900

Non-Insurance Revenues from C_3

Non-Insurance Revenues from Contracts with Customers (Performance obligation) (Details) $ in Billions	Sep. 30, 2024 USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-10-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation, amount	$ 0.4
Remaining performance obligation, expected timing of satisfaction, period	3 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation, amount	$ 1.3
Remaining performance obligation, expected timing of satisfaction, period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation, amount	$ 1
Remaining performance obligation, expected timing of satisfaction, period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2027-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation, amount	$ 1.9
Remaining performance obligation, expected timing of satisfaction, period

Subsequent Events (Details)

Subsequent Events (Details) $ in Millions	1 Months Ended	3 Months Ended		9 Months Ended
	Oct. 31, 2024 USD ($) extensionTerm	Dec. 31, 2024 USD ($)	Sep. 30, 2024 USD ($)	Sep. 30, 2024 USD ($)
Subsequent Event [Line Items]
Pension settlement transaction loss (gain)			$ 4	$ 4
Forecast
Subsequent Event [Line Items]
Pension settlement transaction loss (gain)		$ 370
Pension settlement charge, net of tax		290
Forecast | Minimum | Hurricane Milton
Subsequent Event [Line Items]
Loss from catastrophes		25
Forecast | Maximum | Hurricane Milton
Subsequent Event [Line Items]
Loss from catastrophes		$ 55
Subsequent Event
Subsequent Event [Line Items]
Pension settlement charge	$ 1,045
Number of employees covered by transfer | extensionTerm	7,600
Percentage of defined benefit obligation transferred	60%