CNA Financial (CNA) 10-Q 29 Apr 19 2019 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information Document - shares	3 Months Ended
	Mar. 31, 2019	Apr. 25, 2019
Document and Entity Information [Abstract]
Entity Registrant Name	CNA FINANCIAL CORP
Entity Central Index Key	0000021175
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Document Type	10-Q
Document Period End Date	Mar. 31, 2019
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q1
Amendment Flag	false
Entity Emerging Growth Company	false
Entity Small Business	false
Entity Common Stock, Shares Outstanding (in shares)		271,539,570

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations (Unaudited) - USD ($) shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Revenues
Net earned premiums	$ 1,803	$ 1,785
Net investment income	571	490
Net investment gains:
Other-than-temporary impairment losses	(14)	(6)
Other net investment gains	45	18
Net investment gains	31	12
Non-insurance warranty revenue	281	238
Other revenues	9	10
Total revenues	2,695	2,535
Claims, Benefits and Expenses
Insurance claims and policyholders’ benefits	1,357	1,339
Amortization of deferred acquisition costs	342	296
Non-insurance warranty expense	260	216
Other operating expenses	283	303
Interest	34	35
Total claims, benefits and expenses	2,276	2,189
Income before income tax	419	346
Income tax expense	(77)	(55)
Net income	$ 342	$ 291
Basic earnings per share
Basic earnings per share (in usd per share)	$ 1.26	$ 1.07
Diluted earnings per share
Diluted earnings per share (in usd per share)	1.25	1.07
Dividends declared per share (usd per share)	$ 2.35	$ 2.30
Weighted Average Outstanding Common Stock and Common Stock Equivalents
Basic (in shares)	271.6	271.4
Diluted (in shares)	272.6	272.4

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Comprehensive Income (Loss) (Unaudited) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Net income	$ 342	$ 291
Other Comprehensive Income (Loss), Net of Tax
Net unrealized gains on investments	(530)	438
Foreign currency translation adjustment	17	12
Pension and postretirement benefits	7	10
Other comprehensive income (loss), net of tax	554	(416)
Total comprehensive income (loss)	896	(125)
Net unrealized gains on investments with other-than-temporary impairments
Other Comprehensive Income (Loss), Net of Tax
Net unrealized gains on investments	4	(9)
Net unrealized gains on other investments
Other Comprehensive Income (Loss), Net of Tax
Net unrealized gains on investments	$ (526)	$ 429

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Investments:
Fixed maturity securities at fair value (amortized cost of $37,940 and $38,085)	$ 40,553	$ 39,546
Equity securities at fair value (cost of $812 and $844)	814	780
Limited partnership investments	1,876	1,982
Other invested assets	59	53
Mortgage loans	863	839
Short term investments	1,474	1,286
Total investments	45,639	44,486
Cash	223	310
Reinsurance receivables (less allowance for uncollectible receivables of $29 and $29)	4,277	4,426
Insurance receivables (less allowance for uncollectible receivables of $41 and $42)	2,435	2,323
Accrued investment income	406	391
Deferred acquisition costs	664	633
Deferred income taxes	217	392
Property and equipment at cost (less accumulated depreciation of $214 and $216)	314	324
Goodwill	147	146
Deferred non-insurance warranty acquisition expense	2,576	2,513
Other assets (includes $- and $8 due from Loews Corporation)	1,579	1,208
Total assets	58,477	57,152
Insurance reserves:
Claim and claim adjustment expenses	21,836	21,984
Unearned premiums	4,422	4,183
Future policy benefits	11,078	10,597
Long term debt	2,681	2,680
Deferred non-insurance warranty revenue	3,472	3,402
Other liabilities (includes $31 and $23 due to Loews Corporation)	3,533	3,089
Total liabilities	47,022	45,935
Commitments and contingencies
Stockholders' Equity
Common stock ($2.50 par value; 500,000,000 shares authorized; 273,040,243 shares issued; 271,527,510 and 271,456,978 shares outstanding)	683	683
Additional paid-in capital	2,184	2,192
Retained earnings	8,976	9,277
Accumulated other comprehensive income (loss)	(324)	(878)
Treasury stock (1,512,733 and 1,583,265 shares), at cost	(64)	(57)
Total stockholders’ equity	11,455	11,217
Total liabilities and stockholders' equity	$ 58,477	$ 57,152

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets - (Parenthetical) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Statement of Financial Position [Abstract]
Fixed maturities securities at amortized cost	$ 37,940	$ 38,085
Equity securities at cost	812	844
Allowance for uncollectible reinsurance	29	29
Allowance for uncollectible insurance receivables	41	42
Accumulated depreciation on property and equipment	214	216
Due to related parties	31	23
Due from related parties	$ 0	$ 8
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)	271,527,510	271,456,978
Treasury stock, shares (in shares)	1,512,733	1,583,265

Consolidated Statements of Cash

Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Cash Flows from Operating Activities
Net income	$ 342	$ 291
Adjustments to reconcile net income to net cash flows provided by operating activities:
Deferred income tax expense	32	29
Trading portfolio activity	(3)	(1)
Net investment (gains)	(31)	(12)
Equity method investees	14	(2)
Net amortization of investments	(25)	(15)
Depreciation and amortization	19	20
Changes in:
Receivables, net	44	(215)
Accrued investment income	(15)	(3)
Deferred acquisition costs	(30)	(29)
Insurance reserves	57	311
Other, net	(117)	(156)
Net cash flows provided by operating activities	287	218
Dispositions:
Fixed maturity securities - sales	2,259	2,576
Fixed maturity securities - maturities, calls and redemptions	576	531
Equity securities	64	7
Limited partnerships	186	69
Mortgage loans	35	11
Purchases:
Fixed maturity securities	(2,447)	(2,690)
Equity securities	(36)	(98)
Limited partnerships	(114)	(62)
Mortgage loans	(59)	(36)
Change in other investments	(6)	(4)
Change in short term investments	(177)	208
Purchases of property and equipment	(8)	(38)
Other, net	16	15
Net cash flows provided by investing activities	289	489
Cash Flows from Financing Activities
Dividends paid to common stockholders	(643)	(624)
Repayment of debt	0	(150)
Purchase of treasury stock	(14)	0
Other, net	(8)	(7)
Net cash flows used by financing activities	(665)	(781)
Effect of foreign exchange rate changes on cash	2	1
Net change in cash	(87)	(73)
Cash, beginning of year	310	355
Cash, end of year	$ 223	$ 282

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($)	Total	Common Stock	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Treasury Stock
Total stockholder's equity at beginning of period at Dec. 31, 2017		$ 683,000,000	$ 2,175,000,000	$ 9,364,000,000	$ 16,000,000	$ (60,000,000)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation			(2,000,000)			1,000,000
Dividends to common stockholders ($2.35 and $2.30 per share)				(627,000,000)
Net income	$ 291,000,000			291,000,000
Other comprehensive income (loss)	(416,000,000)				(416,000,000)
Purchase of treasury stock						0
Total stockholder's equity at end of period at Mar. 31, 2018	11,425,000,000	683,000,000	2,173,000,000	9,028,000,000	(400,000,000)	(59,000,000)
Total stockholder's equity at beginning of period at Dec. 31, 2017		683,000,000	2,175,000,000	9,364,000,000	16,000,000	(60,000,000)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Purchase of treasury stock	0
Total stockholder's equity at end of period at Dec. 31, 2018	11,217,000,000	683,000,000	2,192,000,000	9,277,000,000	(878,000,000)	(57,000,000)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation			(8,000,000)			7,000,000
Dividends to common stockholders ($2.35 and $2.30 per share)				(643,000,000)
Net income	342,000,000			342,000,000
Other comprehensive income (loss)	554,000,000				554,000,000
Purchase of treasury stock	(14,000,000)					(14,000,000)
Total stockholder's equity at end of period at Mar. 31, 2019	$ 11,455,000,000	$ 683,000,000	$ 2,184,000,000	$ 8,976,000,000	$ (324,000,000)	$ (64,000,000)

Condensed Consolidated Statem_4

Condensed Consolidated Statements of Stockholders' Equity (Unaudited) - (Parenthetical) - $ / shares	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Statement of Stockholders' Equity [Abstract]
Dividends declared per share (usd per share)	$ 2.35	$ 2.30

General

General	3 Months Ended
	Mar. 31, 2019
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 89% of the outstanding common stock of CNAF as of March 31, 2019 . 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 for the year ended December 31, 2018 , 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 March 31, 2019 and for the three months ended March 31, 2019 and 2018 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. The results of operations for the interim periods are not necessarily indicative of the results to be expected for the full year. Recently Adopted Accounting Standards Updates (ASU) ASU 2016-02: In February 2016, the Financial Accounting Standards Board (FASB) issued ASU No. 2016-02, Leases (Topic 842): Accounting for Leases. The updated accounting guidance requires lessees to recognize on the balance sheet assets and liabilities for the rights and obligations created by the majority of leases, including those historically accounted for as operating leases. On January 1, 2019, the Company adopted the updated guidance using a modified retrospective method. Prior period amounts have not been adjusted and continue to be reported in accordance with the previous accounting guidance. The Company utilized the package of practical expedients allowing the Company to not reassess whether a contract is or contains a lease, lease classification and initial direct costs. The Company also utilized the practical expedient to not separate lease and non-lease components for all leases. Adoption of the updated guidance resulted in the following changes to the Condensed Consolidated Balance Sheet on January 1, 2019: (In millions) Balance as of December 31, 2018 Adjustments Due to Adoption of Topic 842 Balance as of January 1, 2019 Property and equipment at cost (less accumulated depreciation) $ 324 $ 2 $ 326 Other assets 1,208 237 1,445 Other liabilities 3,089 239 3,328 Operating lease right-of-use (ROU) assets, included within Other assets, were reduced by accrued rent and lease incentives of $75 million previously classified as Other liabilities. The updated guidance did not impact the Condensed Consolidated Statements of Operations. See Note K to the Condensed Consolidated Financial Statements for additional information regarding leases. Accounting Standards Pending Adoption In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments-Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments. The updated accounting guidance requires changes to the recognition of credit losses on financial instruments not accounted for at fair value through net income. The guidance is effective for interim and annual periods beginning after December 15, 2019. The guidance will be applied using a modified retrospective approach with the cumulative effect recognized as an adjustment to retained earnings. A prospective transition approach is required for debt securities that have recognized an other-than-temporary impairment prior to the effective date. The Company is currently evaluating the effect the guidance will have on the Company's financial statements, but expects the primary changes to be the use of the expected credit loss model for its mortgage loan portfolio, reinsurance and insurance receivables and other financing receivables and the use of the allowance method rather than the write-down method for credit losses within the available-for-sale fixed maturities portfolio. The expected credit loss model will require a financial asset to be presented at the net amount expected to be collected. The allowance method for available-for-sale debt securities will allow the Company to record reversals of credit losses if the estimate of credit losses declines. In August 2018, the FASB issued ASU 2018-12, Financial Services-Insurance (Topic 944): Targeted Improvements to the Accounting for Long-Duration Contracts

Earnings (Loss) Per Share

Earnings (Loss) Per Share	3 Months Ended
	Mar. 31, 2019
Earnings Per Share [Abstract]
Earnings (Loss) Per Share	Earnings (Loss) Per Share Earnings (loss) per share is based on the 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. For the three months ended March 31, 2019 and 2018 , approximately 971 thousand and 1,009 thousand potential shares attributable to exercises or conversions into common stock under stock-based employee compensation plans were included in the calculation of diluted earnings per share. For the three months ended March 31, 2018 approximately 9 thousand potential shares attributable to exercises or conversions into common stock under stock-based employee compensation plans were not included in the calculation of diluted earnings per share, because the effect would have been antidilutive. For the three months ended March 31, 2019 there were no antidilutive shares. The Company repurchased 317,508 shares of CNA Financial Corporation common stock at an aggregate cost of $ 14 million during the three months ended March 31, 2019 . No repurchases were made during 2018

Investments

Investments	3 Months Ended
	Mar. 31, 2019
Investments [Abstract]
Investments	Investments The significant components of Net investment income are presented in the following table. Three months ended March 31 (In millions) 2019 2018 Fixed maturity securities $ 455 $ 446 Equity securities 30 10 Limited partnership investments 76 30 Mortgage loans 12 11 Short term investments 10 6 Trading portfolio 2 2 Other 2 — Gross investment income 587 505 Investment expense (16 ) (15 ) Net investment income $ 571 $ 490 During the three months ended March 31, 2019 and 2018 , $17 million and less than $1 million of Net investment income was recognized due to the change in fair value of common stock still held as of March 31, 2019 and 2018 . Net investment gains (losses) are presented in the following table. Three months ended March 31 (In millions) 2019 2018 Net investment gains (losses): Fixed maturity securities: Gross gains $ 36 $ 69 Gross losses (42 ) (51 ) Net investment gains (losses) on fixed maturity securities (6 ) 18 Equity securities 42 (15 ) Derivatives (5 ) 5 Short term investments and other — 4 Net investment gains (losses) $ 31 $ 12 During the three months ended March 31, 2019 and 2018 , $42 million of Net investment gains and $15 million of Net investment losses were recognized due to the change in fair value of non-redeemable preferred stock still held as of March 31, 2019 and 2018 . The components of Other-than-temporary impairment (OTTI) losses recognized in earnings by asset type are presented in the following table. Three months ended March 31 (In millions) 2019 2018 Fixed maturity securities available-for-sale: Corporate and other bonds $ 6 $ 5 Asset-backed 8 1 OTTI losses recognized in earnings $ 14 $ 6 The following tables present a summary of fixed maturity securities. March 31, 2019 Cost or Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Unrealized OTTI Losses (Gains) (In millions) Fixed maturity securities available-for-sale: Corporate and other bonds $ 19,296 $ 1,269 $ 99 $ 20,466 $ — States, municipalities and political subdivisions 9,279 1,299 — 10,578 — Asset-backed: Residential mortgage-backed 4,760 92 20 4,832 (22 ) Commercial mortgage-backed 2,026 53 7 2,072 — Other asset-backed 1,877 25 12 1,890 (3 ) Total asset-backed 8,663 170 39 8,794 (25 ) U.S. Treasury and obligations of government-sponsored enterprises 162 3 1 164 — Foreign government 502 12 1 513 — Redeemable preferred stock 10 — — 10 — Total fixed maturity securities available-for-sale 37,912 2,753 140 40,525 $ (25 ) Total fixed maturity securities trading 28 — — 28 Total fixed maturity securities $ 37,940 $ 2,753 $ 140 $ 40,553 December 31, 2018 Cost or Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Unrealized OTTI Losses (Gains) (In millions) Fixed maturity securities available-for-sale: Corporate and other bonds $ 18,764 $ 791 $ 395 $ 19,160 $ — States, municipalities and political subdivisions 9,681 1,076 9 10,748 — Asset-backed: Residential mortgage-backed 4,815 68 57 4,826 (20 ) Commercial mortgage-backed 2,200 28 32 2,196 — Other asset-backed 1,975 11 24 1,962 — Total asset-backed 8,990 107 113 8,984 (20 ) U.S. Treasury and obligations of government-sponsored enterprises 156 3 — 159 — Foreign government 480 5 4 481 — Redeemable preferred stock 10 — — 10 — Total fixed maturity securities available-for-sale 38,081 1,982 521 39,542 $ (20 ) Total fixed maturity securities trading 4 — — 4 Total fixed maturity securities $ 38,085 $ 1,982 $ 521 $ 39,546 The net unrealized gains on investments included in the tables above are recorded as a component of AOCI. When presented in AOCI, these amounts are net of tax and any required Shadow Adjustments. To the extent that unrealized gains on fixed income securities supporting certain products within the Life & Group segment would result in a premium deficiency if realized, a related increase in Insurance reserves is recorded, net of tax, as a reduction of net unrealized gains through Other comprehensive income (loss) (Shadow Adjustments). As of March 31, 2019 and December 31, 2018 , the net unrealized gains on investments included in AOCI were correspondingly reduced by Shadow Adjustments of $1,458 million and $1,078 million . The following tables present the estimated fair value and gross unrealized losses of fixed maturity securities in a gross unrealized loss position by the length of time in which the securities have continuously been in that position. Less than 12 Months 12 Months or Longer Total March 31, 2019 Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses (In millions) Fixed maturity securities available-for-sale: Corporate and other bonds $ 1,656 $ 39 $ 1,743 $ 60 $ 3,399 $ 99 States, municipalities and political subdivisions 14 — 3 — 17 — Asset-backed: Residential mortgage-backed 94 — 1,494 20 1,588 20 Commercial mortgage-backed 184 2 236 5 420 7 Other asset-backed 450 10 95 2 545 12 Total asset-backed 728 12 1,825 27 2,553 39 U.S. Treasury and obligations of government-sponsored enterprises 48 1 14 — 62 1 Foreign government 32 1 27 — 59 1 Total $ 2,478 $ 53 $ 3,612 $ 87 $ 6,090 $ 140 Less than 12 Months 12 Months or Longer Total December 31, 2018 Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses (In millions) Fixed maturity securities available-for-sale: Corporate and other bonds $ 8,543 $ 340 $ 825 $ 55 $ 9,368 $ 395 States, municipalities and political subdivisions 517 8 5 1 522 9 Asset-backed: Residential mortgage-backed 1,932 23 1,119 34 3,051 57 Commercial mortgage-backed 728 10 397 22 1,125 32 Other asset-backed 834 21 125 3 959 24 Total asset-backed 3,494 54 1,641 59 5,135 113 U.S. Treasury and obligations of government-sponsored enterprises 21 — 19 — 40 — Foreign government 114 2 124 2 238 4 Total $ 12,689 $ 404 $ 2,614 $ 117 $ 15,303 $ 521 Based on current facts and circumstances, the Company believes the unrealized losses presented in the March 31, 2019 securities in a gross unrealized loss position table above are not indicative of the ultimate collectibility of the current amortized cost of the securities, but rather are attributable to changes in interest rates, credit spreads and other factors. 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 OTTI losses to be recorded as of March 31, 2019 . The following table presents the activity related to the pretax credit loss component reflected in Retained earnings on fixed maturity securities still held as of March 31, 2019 and 2018 for which a portion of an OTTI loss was recognized in Other comprehensive income (loss). Three months ended March 31 (In millions) 2019 2018 Beginning balance of credit losses on fixed maturity securities $ 18 $ 27 Reductions for securities sold during the period (1 ) (2 ) Ending balance of credit losses on fixed maturity securities $ 17 $ 25 Contractual Maturity The following table presents available-for-sale fixed maturity securities by contractual maturity. March 31, 2019 December 31, 2018 (In millions) Cost or Amortized Cost Estimated Fair Value Cost or Amortized Cost Estimated Fair Value Due in one year or less $ 1,144 $ 1,155 $ 1,350 $ 1,359 Due after one year through five years 7,718 7,992 7,979 8,139 Due after five years through ten years 16,874 17,374 16,859 16,870 Due after ten years 12,176 14,004 11,893 13,174 Total $ 37,912 $ 40,525 $ 38,081 $ 39,542 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. Derivative Financial Instruments The Company holds an embedded derivative on a funds withheld liability with a notional value of $174 million and $172 million as of March 31, 2019 and December 31, 2018 and a fair value of $(2) million and $4 million as of March 31, 2019 and December 31, 2018 . The embedded derivative on the funds withheld liability is accounted for separately and reported with the funds withheld liability in Other liabilities on the Condensed Consolidated Balance Sheets. Investment Commitments As of March 31, 2019 , the Company had committed approximately $597 million to future capital calls from various third-party limited partnership investments in exchange for an ownership interest in the related partnerships. As of March 31, 2019 , the Company had mortgage loan commitments of $9 million representing signed loan applications received and accepted. The Company invests in various privately placed debt securities, including bank loans, as part of its overall investment strategy and has committed to additional future purchases, sales and funding. Purchases and sales of privately placed debt securities are recorded once funded. As of March 31, 2019 , the Company had commitments to purchase or fund additional amounts of $283 million and sell $150 million

Fair Value

Fair Value	3 Months Ended
	Mar. 31, 2019
Fair Value Disclosures [Abstract]
Fair Value	Fair ValueFair 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, iv) deep dives, where the Company performs an independent analysis of the inputs and assumptions used to price individual securities and v) pricing validation, where prices received are compared to prices independently estimated by the Company. 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 U.S. Treasury, government-sponsored enterprises, foreign governments and redeemable preferred stock. March 31, 2019 Total Assets/Liabilities at Fair Value (In millions) Level 1 Level 2 Level 3 Assets Fixed maturity securities: Corporate bonds and other $ 203 $ 20,707 $ 253 $ 21,163 States, municipalities and political subdivisions — 10,596 — 10,596 Asset-backed — 8,610 184 8,794 Total fixed maturity securities 203 39,913 437 40,553 Equity securities: Common stock 136 — 4 140 Non-redeemable preferred stock 50 608 16 674 Total equity securities 186 608 20 814 Short term and other 253 1,126 — 1,379 Total assets $ 642 $ 41,647 $ 457 $ 42,746 Liabilities Other liabilities $ — $ 2 $ — $ 2 Total liabilities $ — $ 2 $ — $ 2 December 31, 2018 Total Assets/Liabilities at Fair Value (In millions) Level 1 Level 2 Level 3 Assets Fixed maturity securities: Corporate bonds and other $ 196 $ 19,396 $ 222 $ 19,814 States, municipalities and political subdivisions — 10,748 — 10,748 Asset-backed — 8,787 197 8,984 Total fixed maturity securities 196 38,931 419 39,546 Equity securities: Common stock 144 — 4 148 Non-redeemable preferred stock 48 570 14 632 Total equity securities 192 570 18 780 Short term and other 216 949 — 1,165 Total assets $ 604 $ 40,450 $ 437 $ 41,491 Liabilities Other liabilities $ — $ (4 ) $ — $ (4 ) Total liabilities $ — $ (4 ) $ — $ (4 ) Level 3 (In millions) Corporate bonds and other States, municipalities and political subdivisions Asset-backed Equity securities Total Balance as of January 1, 2019 $ 222 $ — $ 197 $ 18 $ 437 Total realized and unrealized investment gains (losses): Reported in Net investment gains (losses) — — — 2 2 Reported in Other comprehensive income (loss) 8 — 3 — 11 Total realized and unrealized investment gains (losses) 8 — 3 2 13 Purchases 56 — 20 — 76 Sales — — — — — Settlements (2 ) — (4 ) — (6 ) Transfers into Level 3 — — 5 — 5 Transfers out of Level 3 (31 ) — (37 ) — (68 ) Balance as of March 31, 2019 $ 253 $ — $ 184 $ 20 $ 457 Unrealized gains (losses) on Level 3 assets and liabilities held as of March 31, 2019 recognized in Net income (loss) $ — $ — $ — $ 2 $ 2 Unrealized gains (losses) on Level 3 assets and liabilities held as of March 31, 2019 recognized in Other comprehensive income (loss) 7 — 3 — 10 Level 3 (In millions) Corporate bonds and other States, municipalities and political subdivisions Asset-backed Equity securities Total Balance as of January 1, 2018 $ 98 $ 1 $ 335 $ 20 $ 454 Total realized and unrealized investment gains (losses): Reported in Net investment gains (losses) (1 ) — 7 (2 ) 4 Reported in Other comprehensive income (loss) — — (5 ) — (5 ) Total realized and unrealized investment gains (losses) (1 ) — 2 (2 ) (1 ) Purchases — — 30 — 30 Sales — — (72 ) — (72 ) Settlements (2 ) — (6 ) — (8 ) Transfers into Level 3 5 — — — 5 Transfers out of Level 3 — — (10 ) — (10 ) Balance as of March 31, 2018 $ 100 $ 1 $ 279 $ 18 $ 398 Unrealized gains (losses) on Level 3 assets and liabilities held as of March 31, 2018 recognized in Net income (loss) $ — $ — $ — $ (2 ) $ (2 ) 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 and exchange traded bonds and redeemable preferred stock, 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 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 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 commercial paper, 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 Consolidated Balance Sheets because certain short term investments, such as time deposits, are not measured at fair value. As of March 31, 2019 and December 31, 2018 , there were approximately $54 million and $48 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. Derivative Financial Investments Level 2 investments primarily include the embedded derivative on the funds withheld liability. The embedded derivative on funds withheld liability is valued using the change in fair value of the assets supporting the funds withheld liability, which are fixed maturity securities valued with observable inputs. 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. March 31, 2019 Estimated Fair Value (In millions) Valuation Technique(s) Unobservable Input(s) Range (Weighted Average) Fixed maturity securities $ 293 Discounted cash flow Credit spread 1% - 5% (3%) December 31, 2018 Estimated Fair Value Valuation Technique(s) Unobservable Input(s) Range (Weighted Average) Fixed maturity securities $ 228 Discounted cash flow Credit spread 1% - 12% (3%) 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. March 31, 2019 Carrying Amount Estimated Fair Value (In millions) Level 1 Level 2 Level 3 Total Assets Mortgage loans $ 863 $ — $ — $ 868 $ 868 Note receivable 20 — — 20 20 Liabilities Long term debt $ 2,681 $ — $ 2,792 $ — $ 2,792 December 31, 2018 Carrying Estimated Fair Value (In millions) Level 1 Level 2 Level 3 Total Assets Mortgage loans $ 839 $ — $ — $ 827 $ 827 Note receivable 35 — — 35 35 Liabilities Long term debt $ 2,680 $ — $ 2,731 $ — $ 2,731 The following methods and assumptions were used to estimate the fair value of these financial assets and liabilities. The fair values of mortgage loans were based on the present value of the expected future cash flows discounted at the current interest rate for origination of similar quality loans, adjusted for specific loan risk. The fair value of the note receivable was based on the present value of the expected future cash flows discounted at the current interest rate for origination of similar notes, adjusted for specific credit risk. The note receivable is included within Other assets on the Condensed Consolidated Balance Sheets. The Company's senior notes and debentures were valued based on observable market prices. The fair value for other debt was estimated using discounted cash flows based on current incremental borrowing rates for similar borrowing arrangements.

Claim and Claim Adjustment Expe

Claim and Claim Adjustment Expense Reserves	3 Months Ended
	Mar. 31, 2019
Liability for Claims and Claims Adjustment Expense [Abstract]
Claim and Claim Adjustment Expense Reserves	Claim and Claim Adjustment Expense Reserves Property and casualty insurance 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, as well as court decisions and economic conditions, including 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. 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 $58 million and $34 million for the three months ended March 31, 2019 and 2018 . Net catastrophe losses in the first quarter of 2019 and 2018 related primarily to U.S. 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, including claim and claim adjustment expense reserves of the Life & Group segment. For the three months ended March 31 (In millions) 2019 2018 Reserves, beginning of year: Gross $ 21,984 $ 22,004 Ceded 4,019 3,934 Net reserves, beginning of year 17,965 18,070 Net incurred claim and claim adjustment expenses: Provision for insured events of current year 1,309 1,246 Increase (decrease) in provision for insured events of prior years 8 (34 ) Amortization of discount 50 47 Total net incurred (1) 1,367 1,259 Net payments attributable to: Current year events (100 ) (91 ) Prior year events (1,309 ) (1,219 ) Total net payments (1,409 ) (1,310 ) Foreign currency translation adjustment and other 13 (9 ) Net reserves, end of period 17,936 18,010 Ceded reserves, end of period 3,900 4,057 Gross reserves, end of period $ 21,836 $ 22,067 (1) Total net incurred above 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 and loss deductible receivables, and benefit expenses related to future policy benefits, 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. For the three months ended March 31 (In millions) 2019 2018 Pretax (favorable) unfavorable development: Specialty $ (20 ) $ (30 ) Commercial (8 ) (9 ) International 14 — Corporate & Other — — Total pretax (favorable) unfavorable development $ (14 ) $ (39 ) The following table presents further detail of the development recorded for the Specialty segment. Three months ended March 31 (In millions) 2019 2018 Pretax (favorable) unfavorable development: Medical Professional Liability $ 15 $ 20 Other Professional Liability and Management Liability (12 ) (34 ) Surety (25 ) (15 ) Warranty — — Other 2 (1 ) Total pretax (favorable) unfavorable development $ (20 ) $ (30 ) 2019 Unfavorable development in medical professional liability was primarily due to higher than expected severity in accident year 2013 in our allied healthcare business. Favorable development in other professional liability and management liability was primarily due to lower than expected claim frequency and favorable outcomes on individual claims in accident years 2017 and prior related to financial institutions. This was partially offset by unfavorable development in management liability in accident year 2014 due to large claim activity. Favorable development in surety was due to lower than expected frequency for accident years 2016 and prior. 2018 Unfavorable development in medical professional liability was primarily due to higher than expected severity in accident years 2014 and 2017 in our hospitals business. Favorable development in other professional liability and management liability was primarily due to lower than expected claim frequency in accident years 2013 through 2015 related to financial institutions. The following table presents further detail of the development recorded for the Commercial segment. Three months ended March 31 (In millions) 2019 2018 Pretax (favorable) unfavorable development: Commercial Auto $ (5 ) $ (1 ) General Liability (20 ) (8 ) Workers' Compensation 2 (6 ) Property and Other 15 6 Total pretax (favorable) unfavorable development $ (8 ) $ (9 ) 2019 Favorable development in general liability was primarily due to lower than expected frequency on latent construction defect claims in multiple accident years. Unfavorable development in property and other was primarily due to higher than expected frequency and large loss activity in accident year 2018 in our marine business. 2018 The following table presents further detail of the development recorded for the International segment. Three months ended March 31 (In millions) 2019 2018 Pretax (favorable) unfavorable development: Casualty $ — $ — Property 15 (1 ) Energy and Marine (1 ) — Specialty (1) — 1 Total pretax (favorable) unfavorable development $ 14 $ — (1) Effective January 1, 2019 the Healthcare and Technology line of business has been absorbed within the Specialty line of business in the International segment. Prior period information has been conformed to the new line of business presentation. 2019 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 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 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 following table presents the impact of the Loss Portfolio Transfer on the Condensed Consolidated Statements of Operations. Three months ended March 31 (In millions) 2019 2018 Additional amounts ceded under LPT: Net A&EP adverse development before consideration of LPT $ — $ 113 Provision for uncollectible third-party reinsurance on A&EP — (16 ) Total additional amounts ceded under LPT — 97 Retroactive reinsurance benefit recognized (22 ) (57 ) Pretax impact of deferred retroactive reinsurance $ (22 ) $ 40 The Company intends to complete its annual A&EP reserve review in the fourth quarter of 2019 and maintain this timing for all future annual A&EP reserve reviews. The Company completed A&EP reserve reviews in both the first and fourth quarters of 2018 . Based upon the Company's 2018 first quarter A&EP reserve review, net unfavorable prior year development of $113 million was recognized before consideration of cessions to the LPT for the three months ended March 31, 2018 . The 2018 unfavorable development was driven by higher than anticipated defense costs on direct asbestos and environmental accounts and paid losses on assumed reinsurance exposures. Additionally, in 2018, the Company released a portion of its provision for uncollectible third-party reinsurance. As of March 31, 2019 and December 31, 2018 , the cumulative amounts ceded under the LPT were $3.1 billion . The unrecognized deferred retroactive reinsurance benefit was $352 million and $374 million as of March 31, 2019 and December 31, 2018 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 $3.0 billion and $2.7 billion as of March 31, 2019 and December 31, 2018

Legal Proceedings, Contingencie

Legal Proceedings, Contingencies and Guarantees	3 Months Ended
	Mar. 31, 2019
Legal Proceedings, Commitments and Contingencies, and Guarantees [Abstract]
Legal Proceedings, Contingencies and Guarantees	Legal Proceedings, Contingencies and Guarantees The Company is a party to routine litigation incidental to its business, which, based on the facts and circumstances currently known, is not material to the Company's results of operations or financial position. Guarantees As of March 31, 2019 and December 31, 2018 , the Company had recorded liabilities of approximately $5 million related to guarantee and indemnification agreements and management does not believe that any future indemnity claims will be significantly greater than the amounts recorded. In the course of selling business entities and assets to third parties, the Company agreed to guarantee the performance of certain obligations of previously owned subsidiaries and to indemnify purchasers for losses arising out of breaches of representations and warranties with respect to the business entities or assets sold, including, in certain cases, losses arising from undisclosed liabilities or certain named litigation. Such guarantee and indemnification agreements in effect for sales of business entities, assets and third-party loans may include provisions that survive indefinitely. As of March 31, 2019 , the aggregate amount related to quantifiable guarantees was $375 million and the aggregate amount related to quantifiable indemnification agreements was $252 million . In certain cases, should the Company be required to make payments under any such guarantee, it would have the right to seek reimbursement from an affiliate of a previously owned subsidiary. In addition, the Company has agreed to provide indemnification to third-party purchasers for certain losses associated with sold business entities or assets that are not limited by a contractual monetary amount. As of March 31, 2019 , the Company had outstanding unlimited indemnifications in connection with the sales of certain of its business entities or assets that included tax liabilities arising prior to a purchaser's ownership of an entity or asset, defects in title at the time of sale, employee claims arising prior to closing and in some cases losses arising from certain litigation and undisclosed liabilities. Certain provisions of the indemnification agreements survive indefinitely, while others survive until the applicable statutes of limitation expire, or until the agreed-upon contract terms expire. The Company also provided guarantees, if the primary obligor fails to perform, to holders of structured settlement annuities provided by a previously owned subsidiary. As of March 31, 2019 , the potential amount of future payments the Company could be required to pay under these guarantees was approximately $1.7 billion

Benefit Plans

Benefit Plans	3 Months Ended
	Mar. 31, 2019
Retirement Benefits [Abstract]
Benefit Plans	Benefit Plans The components of net periodic pension cost (benefit) are presented in the following table. Three months ended March 31 (In millions) 2019 2018 Net periodic pension cost (benefit) Service cost $ — $ — Non-service cost (benefit): Interest cost on projected benefit obligation 25 23 Expected return on plan assets (36 ) (40 ) Amortization of net actuarial (gain) loss 10 9 Settlement loss — 4 Total non-service cost (benefit) (1 ) (4 ) Total net periodic pension cost (benefit) $ (1 ) $ (4 ) For the three months ended March 31, 2019 , the Company recognized less than $1 million of non-service benefit in Insurance claims and policyholders' benefits and $1 million of non-service benefit in Other operating expenses. For the three months ended March 31, 2018 , the Company recognized $1 million of non-service cost in Insurance claims and policyholders' benefits and $3 million

Accumulated Other Comprehensive

Accumulated Other Comprehensive Income (Loss) by Component	3 Months Ended
	Mar. 31, 2019
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 OTTI losses Net unrealized gains (losses) on other investments Pension and postretirement benefits Cumulative foreign currency translation adjustment Total Balance as of January 1, 2019 $ 16 $ 61 $ (775 ) $ (180 ) $ (878 ) Other comprehensive income (loss) before reclassifications 4 521 (1 ) 17 541 Amounts reclassified from accumulated other comprehensive income (loss) net of tax (expense) benefit of $-, $1, $2, $- and $3 — (5 ) (8 ) — (13 ) Other comprehensive income (loss) net of tax (expense) benefit of $(1), $(141), $(2), $- and $(144) 4 526 7 17 554 Balance as of March 31, 2019 $ 20 $ 587 $ (768 ) $ (163 ) $ (324 ) (In millions) Net unrealized gains (losses) on investments with OTTI losses Net unrealized gains (losses) on other investments Pension and postretirement benefits Cumulative foreign currency translation adjustment Total Balance as of January 1, 2018 $ 30 $ 859 $ (775 ) $ (98 ) $ 16 Other comprehensive income (loss) before reclassifications (10 ) (414 ) — 12 (412 ) Amounts reclassified from accumulated other comprehensive income (loss) net of tax (expense) benefit of $-, $(4), $3, $- and $(1) (1 ) 15 (10 ) — 4 Other comprehensive income (loss) net of tax (expense) benefit of $2, $109, $(3), $- and $108 (9 ) (429 ) 10 12 (416 ) Balance as of March 31, 2018 $ 21 $ 430 $ (765 ) $ (86 ) $ (400 ) Amounts reclassified from Accumulated other comprehensive income (loss) shown above are reported in Net income (loss) as follows: Component of AOCI Consolidated Statements of Operations Line Item Affected by Reclassifications Net unrealized gains (losses) on investments with OTTI losses Net investment gains (losses) 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	3 Months Ended
	Mar. 31, 2019
Segment Reporting [Abstract]
Business Segments	Business SegmentsThe 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, 2018 . 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 and Net investment gains or losses are 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. Three months ended March 31, 2019 Specialty Commercial International Life & Group Corporate & Other (In millions) Eliminations Total Operating revenues Net earned premiums $ 661 $ 763 $ 250 $ 130 $ — $ (1 ) $ 1,803 Net investment income 155 190 15 204 7 — 571 Non-insurance warranty revenue 281 — — — — — 281 Other revenues 1 7 — 1 2 (2 ) 9 Total operating revenues 1,098 960 265 335 9 (3 ) 2,664 Claims, benefits and expenses Net incurred claims and benefits 392 510 162 308 (21 ) — 1,351 Policyholders’ dividends 1 5 — — — — 6 Amortization of deferred acquisition costs 147 127 68 — — — 342 Non-insurance warranty expense 260 — — — — — 260 Other insurance related expenses 70 130 25 28 (1 ) (1 ) 251 Other expenses 12 11 4 2 39 (2 ) 66 Total claims, benefits and expenses 882 783 259 338 17 (3 ) 2,276 Core income (loss) before income tax 216 177 6 (3 ) (8 ) — 388 Income tax (expense) benefit on core income (loss) (47 ) (38 ) — 13 2 — (70 ) Core income (loss) $ 169 $ 139 $ 6 $ 10 $ (6 ) $ — 318 Net investment gains (losses) 31 Income tax (expense) benefit on net investment gains (losses) (7 ) Net investment gains (losses), after tax 24 Net income $ 342 March 31, 2019 (In millions) Reinsurance receivables $ 674 $ 761 $ 237 $ 408 $ 2,226 $ — $ 4,306 Insurance receivables 933 1,234 302 7 — — 2,476 Deferred acquisition costs 315 247 102 — — — 664 Goodwill 117 — 30 — — — 147 Deferred non-insurance warranty acquisition expense 2,576 — — — — — 2,576 Insurance reserves Claim and claim adjustment expenses 5,470 8,623 1,787 3,645 2,311 — 21,836 Unearned premiums 2,201 1,553 528 142 — (2 ) 4,422 Future policy benefits — — — 11,078 — — 11,078 Deferred non-insurance warranty revenue 3,472 — — — — — 3,472 Three months ended March 31, 2018 Specialty Commercial International Life & Group Corporate & Other (In millions) Eliminations Total Operating revenues Net earned premiums $ 672 $ 743 $ 236 $ 134 $ — $ — $ 1,785 Net investment income 122 149 14 200 5 — 490 Non-insurance warranty revenue 238 — — — — — 238 Other revenues 1 8 — 1 1 (1 ) 10 Total operating revenues 1,033 900 250 335 6 (1 ) 2,523 Claims, benefits and expenses Net incurred claims and benefits 379 468 142 303 41 — 1,333 Policyholders’ dividends 1 5 — — — — 6 Amortization of deferred acquisition costs 145 121 30 — — — 296 Non-insurance warranty expense 216 — — — — — 216 Other insurance related expenses 64 127 56 30 — — 277 Other expenses 11 11 (4 ) 2 42 (1 ) 61 Total claims, benefits and expenses 816 732 224 335 83 (1 ) 2,189 Core income (loss) before income tax 217 168 26 — (77 ) — 334 Income tax (expense) benefit on core income (loss) (46 ) (35 ) (3 ) 14 17 — (53 ) Core income (loss) $ 171 $ 133 $ 23 $ 14 $ (60 ) $ — 281 Net investment gains (losses) 12 Income tax (expense) benefit on net investment gains (losses) (2 ) Net investment gains (losses), after tax 10 Net income $ 291 December 31, 2018 (In millions) Reinsurance receivables $ 649 $ 795 $ 250 $ 414 $ 2,347 $ — $ 4,455 Insurance receivables 947 1,277 284 9 (152 ) — 2,365 Deferred acquisition costs 308 230 95 — — — 633 Goodwill 117 — 29 — — — 146 Deferred non-insurance warranty acquisition expense 2,513 — — — — — 2,513 Insurance reserves Claim and claim adjustment expenses 5,465 8,743 1,750 3,601 2,425 — 21,984 Unearned premiums 2,132 1,454 475 122 — — 4,183 Future policy benefits — — — 10,597 — — 10,597 Deferred non-insurance warranty revenue 3,402 — — — — — 3,402 Three months ended March 31 (In millions) 2019 2018 Specialty Management & Professional Liability $ 636 $ 624 Surety 139 129 Warranty & Alternative Risks 323 280 Specialty revenues 1,098 1,033 Commercial Middle Market 547 504 Small Business 121 119 Other Commercial Insurance 292 277 Commercial revenues 960 900 International Canada 66 58 Europe 91 88 Hardy 108 104 International revenues 265 250 Life & Group revenues 335 335 Corporate & Other revenues 9 6 Eliminations (3 ) (1 ) Total operating revenues 2,664 2,523 Net investment gains (losses) 31 12 Total revenues $ 2,695 $ 2,535

Non-Insurance Revenues from Con

Non-Insurance Revenues from Contracts with Customers	3 Months Ended
	Mar. 31, 2019
Revenue from Contract with Customer [Abstract]
Non-Insurance Revenues from Contracts with Customers	Non-Insurance Revenues from Contracts with Customers The Company had deferred non-insurance warranty revenue balances of $3.5 billion and $3.4 billion reported in Deferred non-insurance warranty revenue as of March 31, 2019 and December 31, 2018 . For the three months ended March 31, 2019 , the Company recognized $265 million of revenues that were included in the deferred revenue balance as of January 1, 2019 . For the three months ended March 31, 2018 , the Company recognized $222 million of revenues that were included in the deferred revenue balance as of January 1, 2018 . For the three months ended March 31, 2019 and 2018 , 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 $754 million of the deferred revenue in the remainder of 2019, $852 million in 2020, $673 million in 2021 and $1.2 billion

Leases

Leases	3 Months Ended
	Mar. 31, 2019
Leases [Abstract]
Leases	Leases A lease provides the lessee the right to control the use of an identified asset for a period of time in exchange for consideration. Operating lease ROU assets and lease liabilities are included in Other assets and Other liabilities on the Company's Condensed Consolidated Balance Sheets. ROU assets represent the Company's right to use an underlying asset for the lease term and operating lease liabilities represent the Company's obligation to make lease payments arising from the lease. The Company determines if an arrangement is a lease at inception. Operating lease ROU assets and liabilities are recognized at the lease commencement date based on the present value of lease payments over the lease term. Most operating leases contain renewal options that provide for rent increases based on prevailing market conditions. Certain leases contain options to terminate before maturity. The lease term used to calculate the ROU asset includes any renewal options or lease termination that the Company expects to exercise. The discount rate used to determine the commencement date present value of lease payments is the interest rate implicit in the lease, or when that is not readily determinable, the Company utilizes its secured borrowing rate. ROU assets include any lease payments required to be made prior to commencement and exclude lease incentives. Both ROU assets and lease liabilities exclude variable payments not based on an index or rate, which are treated as period costs. The Company's lease agreements do not contain significant residual value guarantees, restrictions or covenants. The Company occupies office facilities under lease agreements that expire at various dates. In addition, data processing, office and transportation equipment is leased under agreements that expire at various dates. The Company’s leases generally include lease and non-lease components, which the Company has elected to account for as a single lease component. Variable lease costs not based on an index or rate consist of non-lease components, which are being accounted for as lease components, and represent charges for services provided by the landlord and our reimbursement for the landlord’s costs, including real estate taxes and insurance. The Company does not have any significant finance leases. Operating lease cost was $10 million and variable lease cost was $4 million for the three months ended March 31, 2019 . Cash paid for amounts included in operating lease liabilities was $8 million for the three months ended March 31, 2019 . The table below presents operating lease ROU assets and lease liabilities as of March 31, 2019 : (In millions) March 31, 2019 Operating lease ROU assets $ 233 Operating lease liabilities 308 The table below presents the maturities of operating lease liabilities as of March 31, 2019 : (In millions) Operating Leases 2019 (Excluding the three months ended March 31, 2019) $ 24 2020 40 2021 42 2022 39 2023 33 Thereafter 202 Total lease payments 380 Less: Discount (72 ) Total operating lease liabilities $ 308 The table below presents the weighted average remaining lease term for operating leases and weighted average discount rate used in calculating operating lease right-of-use assets: Three months ended March 31 2019 Weighted average remaining lease term 11.0 years Weighted average discount rate 3.4 % The table below presents the expected future minimum lease payments to be made under non-cancelable operating leases as of December 31, 2018 : (In millions) Future Minimum Lease Payments 2019 $ 35 2020 39 2021 41 2022 38 2023 32 Thereafter 200 Total $ 385

General (Policies)

General (Policies)	3 Months Ended
	Mar. 31, 2019
Accounting Policies [Abstract]
Consolidation	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 89% of the outstanding common stock of CNAF as of March 31, 2019 . 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 for the year ended December 31, 2018 , 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 March 31, 2019 and for the three months ended March 31, 2019 and 2018
Recently Adopted Accounting Standards Updates and Accounting Standards Pending Adoption	Recently Adopted Accounting Standards Updates (ASU) ASU 2016-02: In February 2016, the Financial Accounting Standards Board (FASB) issued ASU No. 2016-02, Leases (Topic 842): Accounting for Leases. The updated accounting guidance requires lessees to recognize on the balance sheet assets and liabilities for the rights and obligations created by the majority of leases, including those historically accounted for as operating leases. On January 1, 2019, the Company adopted the updated guidance using a modified retrospective method. Prior period amounts have not been adjusted and continue to be reported in accordance with the previous accounting guidance. The Company utilized the package of practical expedients allowing the Company to not reassess whether a contract is or contains a lease, lease classification and initial direct costs. The Company also utilized the practical expedient to not separate lease and non-lease components for all leases. Adoption of the updated guidance resulted in the following changes to the Condensed Consolidated Balance Sheet on January 1, 2019: (In millions) Balance as of December 31, 2018 Adjustments Due to Adoption of Topic 842 Balance as of January 1, 2019 Property and equipment at cost (less accumulated depreciation) $ 324 $ 2 $ 326 Other assets 1,208 237 1,445 Other liabilities 3,089 239 3,328 Operating lease right-of-use (ROU) assets, included within Other assets, were reduced by accrued rent and lease incentives of $75 million previously classified as Other liabilities. The updated guidance did not impact the Condensed Consolidated Statements of Operations. See Note K to the Condensed Consolidated Financial Statements for additional information regarding leases. Accounting Standards Pending Adoption In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments-Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments. The updated accounting guidance requires changes to the recognition of credit losses on financial instruments not accounted for at fair value through net income. The guidance is effective for interim and annual periods beginning after December 15, 2019. The guidance will be applied using a modified retrospective approach with the cumulative effect recognized as an adjustment to retained earnings. A prospective transition approach is required for debt securities that have recognized an other-than-temporary impairment prior to the effective date. The Company is currently evaluating the effect the guidance will have on the Company's financial statements, but expects the primary changes to be the use of the expected credit loss model for its mortgage loan portfolio, reinsurance and insurance receivables and other financing receivables and the use of the allowance method rather than the write-down method for credit losses within the available-for-sale fixed maturities portfolio. The expected credit loss model will require a financial asset to be presented at the net amount expected to be collected. The allowance method for available-for-sale debt securities will allow the Company to record reversals of credit losses if the estimate of credit losses declines. In August 2018, the FASB issued ASU 2018-12, Financial Services-Insurance (Topic 944): Targeted Improvements to the Accounting for Long-Duration Contracts

General General (Tables)

General General (Tables)	3 Months Ended
	Mar. 31, 2019
Accounting Policies [Abstract]
Schedule of New Accounting Pronouncements and Changes in Accounting Principles	Adoption of the updated guidance resulted in the following changes to the Condensed Consolidated Balance Sheet on January 1, 2019: (In millions) Balance as of December 31, 2018 Adjustments Due to Adoption of Topic 842 Balance as of January 1, 2019 Property and equipment at cost (less accumulated depreciation) $ 324 $ 2 $ 326 Other assets 1,208 237 1,445 Other liabilities 3,089 239 3,328

Investments (Tables)

Investments (Tables)	3 Months Ended
	Mar. 31, 2019
Investments [Abstract]
Net investment income	The significant components of Net investment income are presented in the following table. Three months ended March 31 (In millions) 2019 2018 Fixed maturity securities $ 455 $ 446 Equity securities 30 10 Limited partnership investments 76 30 Mortgage loans 12 11 Short term investments 10 6 Trading portfolio 2 2 Other 2 — Gross investment income 587 505 Investment expense (16 ) (15 ) Net investment income $ 571 $ 490
Net realized investment gains (losses)	Net investment gains (losses) are presented in the following table. Three months ended March 31 (In millions) 2019 2018 Net investment gains (losses): Fixed maturity securities: Gross gains $ 36 $ 69 Gross losses (42 ) (51 ) Net investment gains (losses) on fixed maturity securities (6 ) 18 Equity securities 42 (15 ) Derivatives (5 ) 5 Short term investments and other — 4 Net investment gains (losses) $ 31 $ 12
Components of net other than temporary impairment losses recognized in earnings by asset type	The components of Other-than-temporary impairment (OTTI) losses recognized in earnings by asset type are presented in the following table. Three months ended March 31 (In millions) 2019 2018 Fixed maturity securities available-for-sale: Corporate and other bonds $ 6 $ 5 Asset-backed 8 1 OTTI losses recognized in earnings $ 14 $ 6
Summary of fixed maturity and equity securities	The following tables present a summary of fixed maturity securities. March 31, 2019 Cost or Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Unrealized OTTI Losses (Gains) (In millions) Fixed maturity securities available-for-sale: Corporate and other bonds $ 19,296 $ 1,269 $ 99 $ 20,466 $ — States, municipalities and political subdivisions 9,279 1,299 — 10,578 — Asset-backed: Residential mortgage-backed 4,760 92 20 4,832 (22 ) Commercial mortgage-backed 2,026 53 7 2,072 — Other asset-backed 1,877 25 12 1,890 (3 ) Total asset-backed 8,663 170 39 8,794 (25 ) U.S. Treasury and obligations of government-sponsored enterprises 162 3 1 164 — Foreign government 502 12 1 513 — Redeemable preferred stock 10 — — 10 — Total fixed maturity securities available-for-sale 37,912 2,753 140 40,525 $ (25 ) Total fixed maturity securities trading 28 — — 28 Total fixed maturity securities $ 37,940 $ 2,753 $ 140 $ 40,553 December 31, 2018 Cost or Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Unrealized OTTI Losses (Gains) (In millions) Fixed maturity securities available-for-sale: Corporate and other bonds $ 18,764 $ 791 $ 395 $ 19,160 $ — States, municipalities and political subdivisions 9,681 1,076 9 10,748 — Asset-backed: Residential mortgage-backed 4,815 68 57 4,826 (20 ) Commercial mortgage-backed 2,200 28 32 2,196 — Other asset-backed 1,975 11 24 1,962 — Total asset-backed 8,990 107 113 8,984 (20 ) U.S. Treasury and obligations of government-sponsored enterprises 156 3 — 159 — Foreign government 480 5 4 481 — Redeemable preferred stock 10 — — 10 — Total fixed maturity securities available-for-sale 38,081 1,982 521 39,542 $ (20 ) Total fixed maturity securities trading 4 — — 4 Total fixed maturity securities $ 38,085 $ 1,982 $ 521 $ 39,546
Securities in a gross unrealized loss position	The following tables present the estimated fair value and gross unrealized losses of fixed maturity securities in a gross unrealized loss position by the length of time in which the securities have continuously been in that position. Less than 12 Months 12 Months or Longer Total March 31, 2019 Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses (In millions) Fixed maturity securities available-for-sale: Corporate and other bonds $ 1,656 $ 39 $ 1,743 $ 60 $ 3,399 $ 99 States, municipalities and political subdivisions 14 — 3 — 17 — Asset-backed: Residential mortgage-backed 94 — 1,494 20 1,588 20 Commercial mortgage-backed 184 2 236 5 420 7 Other asset-backed 450 10 95 2 545 12 Total asset-backed 728 12 1,825 27 2,553 39 U.S. Treasury and obligations of government-sponsored enterprises 48 1 14 — 62 1 Foreign government 32 1 27 — 59 1 Total $ 2,478 $ 53 $ 3,612 $ 87 $ 6,090 $ 140 Less than 12 Months 12 Months or Longer Total December 31, 2018 Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses (In millions) Fixed maturity securities available-for-sale: Corporate and other bonds $ 8,543 $ 340 $ 825 $ 55 $ 9,368 $ 395 States, municipalities and political subdivisions 517 8 5 1 522 9 Asset-backed: Residential mortgage-backed 1,932 23 1,119 34 3,051 57 Commercial mortgage-backed 728 10 397 22 1,125 32 Other asset-backed 834 21 125 3 959 24 Total asset-backed 3,494 54 1,641 59 5,135 113 U.S. Treasury and obligations of government-sponsored enterprises 21 — 19 — 40 — Foreign government 114 2 124 2 238 4 Total $ 12,689 $ 404 $ 2,614 $ 117 $ 15,303 $ 521
Activity related to the pretax fixed maturity credit loss component reflected within retained earnings for securities still held for which a portion of an OTTI loss was recognized in OCI	The following table presents the activity related to the pretax credit loss component reflected in Retained earnings on fixed maturity securities still held as of March 31, 2019 and 2018 for which a portion of an OTTI loss was recognized in Other comprehensive income (loss). Three months ended March 31 (In millions) 2019 2018 Beginning balance of credit losses on fixed maturity securities $ 18 $ 27 Reductions for securities sold during the period (1 ) (2 ) Ending balance of credit losses on fixed maturity securities $ 17 $ 25
Contractual maturity	The following table presents available-for-sale fixed maturity securities by contractual maturity. March 31, 2019 December 31, 2018 (In millions) Cost or Amortized Cost Estimated Fair Value Cost or Amortized Cost Estimated Fair Value Due in one year or less $ 1,144 $ 1,155 $ 1,350 $ 1,359 Due after one year through five years 7,718 7,992 7,979 8,139 Due after five years through ten years 16,874 17,374 16,859 16,870 Due after ten years 12,176 14,004 11,893 13,174 Total $ 37,912 $ 40,525 $ 38,081 $ 39,542

Fair Value (Tables)

Fair Value (Tables)	3 Months Ended
	Mar. 31, 2019
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 U.S. Treasury, government-sponsored enterprises, foreign governments and redeemable preferred stock. March 31, 2019 Total Assets/Liabilities at Fair Value (In millions) Level 1 Level 2 Level 3 Assets Fixed maturity securities: Corporate bonds and other $ 203 $ 20,707 $ 253 $ 21,163 States, municipalities and political subdivisions — 10,596 — 10,596 Asset-backed — 8,610 184 8,794 Total fixed maturity securities 203 39,913 437 40,553 Equity securities: Common stock 136 — 4 140 Non-redeemable preferred stock 50 608 16 674 Total equity securities 186 608 20 814 Short term and other 253 1,126 — 1,379 Total assets $ 642 $ 41,647 $ 457 $ 42,746 Liabilities Other liabilities $ — $ 2 $ — $ 2 Total liabilities $ — $ 2 $ — $ 2 December 31, 2018 Total Assets/Liabilities at Fair Value (In millions) Level 1 Level 2 Level 3 Assets Fixed maturity securities: Corporate bonds and other $ 196 $ 19,396 $ 222 $ 19,814 States, municipalities and political subdivisions — 10,748 — 10,748 Asset-backed — 8,787 197 8,984 Total fixed maturity securities 196 38,931 419 39,546 Equity securities: Common stock 144 — 4 148 Non-redeemable preferred stock 48 570 14 632 Total equity securities 192 570 18 780 Short term and other 216 949 — 1,165 Total assets $ 604 $ 40,450 $ 437 $ 41,491 Liabilities Other liabilities $ — $ (4 ) $ — $ (4 ) Total liabilities $ — $ (4 ) $ — $ (4 )
Table of reconciliation for assets and liablities 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 January 1, 2019 $ 222 $ — $ 197 $ 18 $ 437 Total realized and unrealized investment gains (losses): Reported in Net investment gains (losses) — — — 2 2 Reported in Other comprehensive income (loss) 8 — 3 — 11 Total realized and unrealized investment gains (losses) 8 — 3 2 13 Purchases 56 — 20 — 76 Sales — — — — — Settlements (2 ) — (4 ) — (6 ) Transfers into Level 3 — — 5 — 5 Transfers out of Level 3 (31 ) — (37 ) — (68 ) Balance as of March 31, 2019 $ 253 $ — $ 184 $ 20 $ 457 Unrealized gains (losses) on Level 3 assets and liabilities held as of March 31, 2019 recognized in Net income (loss) $ — $ — $ — $ 2 $ 2 Unrealized gains (losses) on Level 3 assets and liabilities held as of March 31, 2019 recognized in Other comprehensive income (loss) 7 — 3 — 10 Level 3 (In millions) Corporate bonds and other States, municipalities and political subdivisions Asset-backed Equity securities Total Balance as of January 1, 2018 $ 98 $ 1 $ 335 $ 20 $ 454 Total realized and unrealized investment gains (losses): Reported in Net investment gains (losses) (1 ) — 7 (2 ) 4 Reported in Other comprehensive income (loss) — — (5 ) — (5 ) Total realized and unrealized investment gains (losses) (1 ) — 2 (2 ) (1 ) Purchases — — 30 — 30 Sales — — (72 ) — (72 ) Settlements (2 ) — (6 ) — (8 ) Transfers into Level 3 5 — — — 5 Transfers out of Level 3 — — (10 ) — (10 ) Balance as of March 31, 2018 $ 100 $ 1 $ 279 $ 18 $ 398 Unrealized gains (losses) on Level 3 assets and liabilities held as of March 31, 2018 recognized in Net income (loss) $ — $ — $ — $ (2 ) $ (2 )
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. March 31, 2019 Estimated Fair Value (In millions) Valuation Technique(s) Unobservable Input(s) Range (Weighted Average) Fixed maturity securities $ 293 Discounted cash flow Credit spread 1% - 5% (3%) December 31, 2018 Estimated Fair Value Valuation Technique(s) Unobservable Input(s) Range (Weighted Average) Fixed maturity securities $ 228 Discounted cash flow Credit spread 1% - 12% (3%)
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. March 31, 2019 Carrying Amount Estimated Fair Value (In millions) Level 1 Level 2 Level 3 Total Assets Mortgage loans $ 863 $ — $ — $ 868 $ 868 Note receivable 20 — — 20 20 Liabilities Long term debt $ 2,681 $ — $ 2,792 $ — $ 2,792 December 31, 2018 Carrying Estimated Fair Value (In millions) Level 1 Level 2 Level 3 Total Assets Mortgage loans $ 839 $ — $ — $ 827 $ 827 Note receivable 35 — — 35 35 Liabilities Long term debt $ 2,680 $ — $ 2,731 $ — $ 2,731

Claim and Claim Adjustment Ex_2

Claim and Claim Adjustment Expense Reserves (Tables)	3 Months Ended
	Mar. 31, 2019
Net Incurred Claim and Claim Adjustment Expense [Line Items]
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, including claim and claim adjustment expense reserves of the Life & Group segment. For the three months ended March 31 (In millions) 2019 2018 Reserves, beginning of year: Gross $ 21,984 $ 22,004 Ceded 4,019 3,934 Net reserves, beginning of year 17,965 18,070 Net incurred claim and claim adjustment expenses: Provision for insured events of current year 1,309 1,246 Increase (decrease) in provision for insured events of prior years 8 (34 ) Amortization of discount 50 47 Total net incurred (1) 1,367 1,259 Net payments attributable to: Current year events (100 ) (91 ) Prior year events (1,309 ) (1,219 ) Total net payments (1,409 ) (1,310 ) Foreign currency translation adjustment and other 13 (9 ) Net reserves, end of period 17,936 18,010 Ceded reserves, end of period 3,900 4,057 Gross reserves, end of period $ 21,836 $ 22,067 (1)
Net prior year development	The following table presents development recorded for the Specialty, Commercial, International and Corporate & Other segments. For the three months ended March 31 (In millions) 2019 2018 Pretax (favorable) unfavorable development: Specialty $ (20 ) $ (30 ) Commercial (8 ) (9 ) International 14 — Corporate & Other — — Total pretax (favorable) unfavorable development $ (14 ) $ (39 )
Specialty
Net Incurred Claim and Claim Adjustment Expense [Line Items]
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. Three months ended March 31 (In millions) 2019 2018 Pretax (favorable) unfavorable development: Medical Professional Liability $ 15 $ 20 Other Professional Liability and Management Liability (12 ) (34 ) Surety (25 ) (15 ) Warranty — — Other 2 (1 ) Total pretax (favorable) unfavorable development $ (20 ) $ (30 )
Commercial
Net Incurred Claim and Claim Adjustment Expense [Line Items]
Net prior year claim and allocated claim adjustment expense reserve development	The following table presents further detail of the development recorded for the Commercial segment. Three months ended March 31 (In millions) 2019 2018 Pretax (favorable) unfavorable development: Commercial Auto $ (5 ) $ (1 ) General Liability (20 ) (8 ) Workers' Compensation 2 (6 ) Property and Other 15 6 Total pretax (favorable) unfavorable development $ (8 ) $ (9 )
International
Net Incurred Claim and Claim Adjustment Expense [Line Items]
Net prior year claim and allocated claim adjustment expense reserve development	The following table presents further detail of the development recorded for the International segment. Three months ended March 31 (In millions) 2019 2018 Pretax (favorable) unfavorable development: Casualty $ — $ — Property 15 (1 ) Energy and Marine (1 ) — Specialty (1) — 1 Total pretax (favorable) unfavorable development $ 14 $ — (1) Effective January 1, 2019
CNAF Consolidated
Net Incurred Claim and Claim Adjustment Expense [Line Items]
Impact of loss portfolio transfer on the consolidated statement of operations	The following table presents the impact of the Loss Portfolio Transfer on the Condensed Consolidated Statements of Operations. Three months ended March 31 (In millions) 2019 2018 Additional amounts ceded under LPT: Net A&EP adverse development before consideration of LPT $ — $ 113 Provision for uncollectible third-party reinsurance on A&EP — (16 ) Total additional amounts ceded under LPT — 97 Retroactive reinsurance benefit recognized (22 ) (57 ) Pretax impact of deferred retroactive reinsurance $ (22 ) $ 40

Benefit Plans (Tables)

Benefit Plans (Tables)	3 Months Ended
	Mar. 31, 2019
Retirement Benefits [Abstract]
Components of net periodic cost (benefit)	The components of net periodic pension cost (benefit) are presented in the following table. Three months ended March 31 (In millions) 2019 2018 Net periodic pension cost (benefit) Service cost $ — $ — Non-service cost (benefit): Interest cost on projected benefit obligation 25 23 Expected return on plan assets (36 ) (40 ) Amortization of net actuarial (gain) loss 10 9 Settlement loss — 4 Total non-service cost (benefit) (1 ) (4 ) Total net periodic pension cost (benefit) $ (1 ) $ (4 )

Accumulated Other Comprehensi_2

Accumulated Other Comprehensive Income (Loss) by Component (Tables)	3 Months Ended
	Mar. 31, 2019
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 OTTI losses Net unrealized gains (losses) on other investments Pension and postretirement benefits Cumulative foreign currency translation adjustment Total Balance as of January 1, 2019 $ 16 $ 61 $ (775 ) $ (180 ) $ (878 ) Other comprehensive income (loss) before reclassifications 4 521 (1 ) 17 541 Amounts reclassified from accumulated other comprehensive income (loss) net of tax (expense) benefit of $-, $1, $2, $- and $3 — (5 ) (8 ) — (13 ) Other comprehensive income (loss) net of tax (expense) benefit of $(1), $(141), $(2), $- and $(144) 4 526 7 17 554 Balance as of March 31, 2019 $ 20 $ 587 $ (768 ) $ (163 ) $ (324 ) (In millions) Net unrealized gains (losses) on investments with OTTI losses Net unrealized gains (losses) on other investments Pension and postretirement benefits Cumulative foreign currency translation adjustment Total Balance as of January 1, 2018 $ 30 $ 859 $ (775 ) $ (98 ) $ 16 Other comprehensive income (loss) before reclassifications (10 ) (414 ) — 12 (412 ) Amounts reclassified from accumulated other comprehensive income (loss) net of tax (expense) benefit of $-, $(4), $3, $- and $(1) (1 ) 15 (10 ) — 4 Other comprehensive income (loss) net of tax (expense) benefit of $2, $109, $(3), $- and $108 (9 ) (429 ) 10 12 (416 ) Balance as of March 31, 2018 $ 21 $ 430 $ (765 ) $ (86 ) $ (400 )
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 Consolidated Statements of Operations Line Item Affected by Reclassifications Net unrealized gains (losses) on investments with OTTI losses Net investment gains (losses) 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)	3 Months Ended
	Mar. 31, 2019
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 March 31, 2019 Specialty Commercial International Life & Group Corporate & Other (In millions) Eliminations Total Operating revenues Net earned premiums $ 661 $ 763 $ 250 $ 130 $ — $ (1 ) $ 1,803 Net investment income 155 190 15 204 7 — 571 Non-insurance warranty revenue 281 — — — — — 281 Other revenues 1 7 — 1 2 (2 ) 9 Total operating revenues 1,098 960 265 335 9 (3 ) 2,664 Claims, benefits and expenses Net incurred claims and benefits 392 510 162 308 (21 ) — 1,351 Policyholders’ dividends 1 5 — — — — 6 Amortization of deferred acquisition costs 147 127 68 — — — 342 Non-insurance warranty expense 260 — — — — — 260 Other insurance related expenses 70 130 25 28 (1 ) (1 ) 251 Other expenses 12 11 4 2 39 (2 ) 66 Total claims, benefits and expenses 882 783 259 338 17 (3 ) 2,276 Core income (loss) before income tax 216 177 6 (3 ) (8 ) — 388 Income tax (expense) benefit on core income (loss) (47 ) (38 ) — 13 2 — (70 ) Core income (loss) $ 169 $ 139 $ 6 $ 10 $ (6 ) $ — 318 Net investment gains (losses) 31 Income tax (expense) benefit on net investment gains (losses) (7 ) Net investment gains (losses), after tax 24 Net income $ 342 March 31, 2019 (In millions) Reinsurance receivables $ 674 $ 761 $ 237 $ 408 $ 2,226 $ — $ 4,306 Insurance receivables 933 1,234 302 7 — — 2,476 Deferred acquisition costs 315 247 102 — — — 664 Goodwill 117 — 30 — — — 147 Deferred non-insurance warranty acquisition expense 2,576 — — — — — 2,576 Insurance reserves Claim and claim adjustment expenses 5,470 8,623 1,787 3,645 2,311 — 21,836 Unearned premiums 2,201 1,553 528 142 — (2 ) 4,422 Future policy benefits — — — 11,078 — — 11,078 Deferred non-insurance warranty revenue 3,472 — — — — — 3,472 Three months ended March 31, 2018 Specialty Commercial International Life & Group Corporate & Other (In millions) Eliminations Total Operating revenues Net earned premiums $ 672 $ 743 $ 236 $ 134 $ — $ — $ 1,785 Net investment income 122 149 14 200 5 — 490 Non-insurance warranty revenue 238 — — — — — 238 Other revenues 1 8 — 1 1 (1 ) 10 Total operating revenues 1,033 900 250 335 6 (1 ) 2,523 Claims, benefits and expenses Net incurred claims and benefits 379 468 142 303 41 — 1,333 Policyholders’ dividends 1 5 — — — — 6 Amortization of deferred acquisition costs 145 121 30 — — — 296 Non-insurance warranty expense 216 — — — — — 216 Other insurance related expenses 64 127 56 30 — — 277 Other expenses 11 11 (4 ) 2 42 (1 ) 61 Total claims, benefits and expenses 816 732 224 335 83 (1 ) 2,189 Core income (loss) before income tax 217 168 26 — (77 ) — 334 Income tax (expense) benefit on core income (loss) (46 ) (35 ) (3 ) 14 17 — (53 ) Core income (loss) $ 171 $ 133 $ 23 $ 14 $ (60 ) $ — 281 Net investment gains (losses) 12 Income tax (expense) benefit on net investment gains (losses) (2 ) Net investment gains (losses), after tax 10 Net income $ 291 December 31, 2018 (In millions) Reinsurance receivables $ 649 $ 795 $ 250 $ 414 $ 2,347 $ — $ 4,455 Insurance receivables 947 1,277 284 9 (152 ) — 2,365 Deferred acquisition costs 308 230 95 — — — 633 Goodwill 117 — 29 — — — 146 Deferred non-insurance warranty acquisition expense 2,513 — — — — — 2,513 Insurance reserves Claim and claim adjustment expenses 5,465 8,743 1,750 3,601 2,425 — 21,984 Unearned premiums 2,132 1,454 475 122 — — 4,183 Future policy benefits — — — 10,597 — — 10,597 Deferred non-insurance warranty revenue 3,402 — — — — — 3,402
Revenues by line of business	The following table presents operating revenue by line of business for each reportable segment. Three months ended March 31 (In millions) 2019 2018 Specialty Management & Professional Liability $ 636 $ 624 Surety 139 129 Warranty & Alternative Risks 323 280 Specialty revenues 1,098 1,033 Commercial Middle Market 547 504 Small Business 121 119 Other Commercial Insurance 292 277 Commercial revenues 960 900 International Canada 66 58 Europe 91 88 Hardy 108 104 International revenues 265 250 Life & Group revenues 335 335 Corporate & Other revenues 9 6 Eliminations (3 ) (1 ) Total operating revenues 2,664 2,523 Net investment gains (losses) 31 12 Total revenues $ 2,695 $ 2,535

Leases (Tables)

Leases (Tables)	3 Months Ended
	Mar. 31, 2019
Leases [Abstract]
Assets and Liabilities, Lessee	The table below presents operating lease ROU assets and lease liabilities as of March 31, 2019 : (In millions) March 31, 2019 Operating lease ROU assets $ 233 Operating lease liabilities 308
Maturities of Operating Lease Liabilities	The table below presents the maturities of operating lease liabilities as of March 31, 2019 : (In millions) Operating Leases 2019 (Excluding the three months ended March 31, 2019) $ 24 2020 40 2021 42 2022 39 2023 33 Thereafter 202 Total lease payments 380 Less: Discount (72 ) Total operating lease liabilities $ 308
Lease Terms And Discount Rates	The table below presents the weighted average remaining lease term for operating leases and weighted average discount rate used in calculating operating lease right-of-use assets: Three months ended March 31 2019 Weighted average remaining lease term 11.0 years Weighted average discount rate 3.4 %
Schedule of Future Minimum Rental Payments for Operating Leases	The table below presents the expected future minimum lease payments to be made under non-cancelable operating leases as of December 31, 2018 : (In millions) Future Minimum Lease Payments 2019 $ 35 2020 39 2021 41 2022 38 2023 32 Thereafter 200 Total $ 385

General (Narrative) (Details)

General (Narrative) (Details) - USD ($) $ in Millions	Mar. 31, 2019	Jan. 01, 2019	Dec. 31, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Other assets	$ (1,579)	$ (1,445)	$ (1,208)
CNAF Consolidated | Loews
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Noncontrolling interest, ownership percentage by parent	89.00%
Adjustments Due to Adoption of Topic 842
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Other assets	$ 75	$ (237)

General (Adoption of Updated Gu

General (Adoption of Updated Guidance) (Details) - USD ($) $ in Millions	Mar. 31, 2019	Jan. 01, 2019	Dec. 31, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Property and equipment at cost (less accumulated depreciation)	$ 314	$ 326	$ 324
Other Assets	1,579	1,445	1,208
Other liabilities	3,533	3,328	$ 3,089
Adjustments Due to Adoption of Topic 842
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Property and equipment at cost (less accumulated depreciation)		2
Other Assets	$ (75)	237
Other liabilities		$ 239

Earnings (Loss) Per Share (Deta

Earnings (Loss) Per Share (Details) - USD ($)	3 Months Ended		12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Earnings Per Share [Abstract]
Incremental common shares attributable to Dilutive effect of share-based payment arrangements (in shares)	971,000	1,009,000
Antidilutive securities excluded from computation of earnings per share, amount (in shares)	0	9,000
Number of repurchased shares (in shares)	317,508
Cost of repurchased stock	$ 14,000,000		$ 0

Investments (Net investment inc

Investments (Net investment income) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Net Investment Income [Line Items]
Gross investment income	$ 587	$ 505
Investment expense	(16)	(15)
Net investment income	571	490
Fixed maturity securities
Net Investment Income [Line Items]
Gross investment income	455	446
Equity securities
Net Investment Income [Line Items]
Gross investment income	30	10
Limited partnership investments
Net Investment Income [Line Items]
Gross investment income	76	30
Mortgage loans
Net Investment Income [Line Items]
Gross investment income	12	11
Short term investments
Net Investment Income [Line Items]
Gross investment income	10	6
Trading portfolio
Net Investment Income [Line Items]
Gross investment income	2	2
Other
Net Investment Income [Line Items]
Gross investment income	$ 2	$ 0

Investments (Narrative) (Detail

Investments (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Gain (Loss) on Securities [Line Items]
Reduction of net unrealized gains on investments included in AOCI due to shadow adjustments	$ 1,458		$ 1,078
Derivative, notional amount	174		172
Derivative liability	(2)
Derivative asset, fair value, gross asset			$ 4
Future capital call commitments for limited partnership investments	597
Mortgage loan commitments	9
Commitments to purchase or fund privately placed debt securities	283
Commitments to sell various privately placed debt securities	150
Common Stock
Gain (Loss) on Securities [Line Items]
Equity securities, FV-NI, gain (loss)	17	$ 1
Preferred stock
Gain (Loss) on Securities [Line Items]
Equity securities, FV-NI, gain (loss)	$ 42	$ (15)

Investments (Net realized inves

Investments (Net realized investment gains (losses)) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Fixed maturity securities:
Gross gains	$ 36	$ 69
Gross losses	(42)	(51)
Net investment gains (losses) on fixed maturity securities	(6)	18
Equity securities	42	(15)
Derivatives	(5)	5
Short term investments and other	0	4
Net investment gains	$ 31	$ 12

Investments (Components of othe

Investments (Components of other-than-temporary impairment losses recognized in earnings) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Debt Securities, Available-for-sale [Line Items]
Total fixed maturity securities available-for-sale	$ 14	$ 6
Corporate and other bonds
Debt Securities, Available-for-sale [Line Items]
Total fixed maturity securities available-for-sale	6	5
Asset-backed
Debt Securities, Available-for-sale [Line Items]
Total fixed maturity securities available-for-sale	$ 8	$ 1

Investments (Summary of fixed m

Investments (Summary of fixed maturity and equity securities) (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Fixed maturity securities available-for-sale:
Cost or Amortized Cost	$ 37,912	$ 38,081
Gross Unrealized Gains	2,753	1,982
Gross Unrealized Losses	140	521
Estimated Fair Value	40,525	39,542
Total fixed maturity securities trading
Debt securities, amortized cost	37,940	38,085
Debt securities	40,553	39,546
Corporate and other bonds
Fixed maturity securities available-for-sale:
Cost or Amortized Cost	19,296	18,764
Gross Unrealized Gains	1,269	791
Gross Unrealized Losses	99	395
Estimated Fair Value	20,466	19,160
Total fixed maturity securities trading
Debt securities	21,163	19,814
Unrealized OTTI Losses (Gains)	0	0
States, municipalities and political subdivisions
Fixed maturity securities available-for-sale:
Cost or Amortized Cost	9,279	9,681
Gross Unrealized Gains	1,299	1,076
Gross Unrealized Losses	0	9
Estimated Fair Value	10,578	10,748
Total fixed maturity securities trading
Debt securities	10,596	10,748
Unrealized OTTI Losses (Gains)	0	0
Residential mortgage-backed
Fixed maturity securities available-for-sale:
Cost or Amortized Cost	4,760	4,815
Gross Unrealized Gains	92	68
Gross Unrealized Losses	20	57
Estimated Fair Value	4,832	4,826
Total fixed maturity securities trading
Unrealized OTTI Losses (Gains)	(22)	(20)
Commercial mortgage-backed
Fixed maturity securities available-for-sale:
Cost or Amortized Cost	2,026	2,200
Gross Unrealized Gains	53	28
Gross Unrealized Losses	7	32
Estimated Fair Value	2,072	2,196
Total fixed maturity securities trading
Unrealized OTTI Losses (Gains)	0	0
Other asset-backed
Fixed maturity securities available-for-sale:
Cost or Amortized Cost	1,877	1,975
Gross Unrealized Gains	25	11
Gross Unrealized Losses	12	24
Estimated Fair Value	1,890	1,962
Total fixed maturity securities trading
Unrealized OTTI Losses (Gains)	(3)	0
Asset-backed
Fixed maturity securities available-for-sale:
Cost or Amortized Cost	8,663	8,990
Gross Unrealized Gains	170	107
Gross Unrealized Losses	39	113
Estimated Fair Value	8,794	8,984
Total fixed maturity securities trading
Debt securities	8,794	8,984
Unrealized OTTI Losses (Gains)	(25)	(20)
U.S. Treasury and obligations of government-sponsored enterprises
Fixed maturity securities available-for-sale:
Cost or Amortized Cost	162	156
Gross Unrealized Gains	3	3
Gross Unrealized Losses	1	0
Estimated Fair Value	164	159
Total fixed maturity securities trading
Unrealized OTTI Losses (Gains)	0	0
Foreign government
Fixed maturity securities available-for-sale:
Cost or Amortized Cost	502	480
Gross Unrealized Gains	12	5
Gross Unrealized Losses	1	4
Estimated Fair Value	513	481
Total fixed maturity securities trading
Unrealized OTTI Losses (Gains)	0	0
Redeemable preferred stock
Fixed maturity securities available-for-sale:
Cost or Amortized Cost	10	10
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	10	10
Total fixed maturity securities trading
Unrealized OTTI Losses (Gains)	0	0
Fixed maturity securities
Fixed maturity securities available-for-sale:
Cost or Amortized Cost	37,912	38,081
Gross Unrealized Gains	2,753	1,982
Gross Unrealized Losses	140	521
Estimated Fair Value	40,525	39,542
Total fixed maturity securities trading
Unrealized OTTI Losses (Gains)	(25)	(20)
Total fixed maturity securities trading
Total fixed maturity securities trading
Cost or amortized cost, trading securities	28	4
Estimated fair value, trading securities	$ 28	$ 4

Investments (Securities in a gr

Investments (Securities in a gross unrealized loss position) (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value, Less than 12 months	$ 2,478	$ 12,689
Gross Unrealized Losses, Less than 12 Months	53	404
Estimated Fair Value, 12 Months or Longer	3,612	2,614
Gross Unrealized Losses, 12 Months or Longer	87	117
Estimated Fair Value, Total	6,090	15,303
Gross Unrealized Losses, Total	140	521
Corporate and other bonds
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value, Less than 12 months	1,656	8,543
Gross Unrealized Losses, Less than 12 Months	39	340
Estimated Fair Value, 12 Months or Longer	1,743	825
Gross Unrealized Losses, 12 Months or Longer	60	55
Estimated Fair Value, Total	3,399	9,368
Gross Unrealized Losses, Total	99	395
States, municipalities and political subdivisions
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value, Less than 12 months	14	517
Gross Unrealized Losses, Less than 12 Months	0	8
Estimated Fair Value, 12 Months or Longer	3	5
Gross Unrealized Losses, 12 Months or Longer	0	1
Estimated Fair Value, Total	17	522
Gross Unrealized Losses, Total		9
Residential mortgage-backed
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value, Less than 12 months	94	1,932
Gross Unrealized Losses, Less than 12 Months	0	23
Estimated Fair Value, 12 Months or Longer	1,494	1,119
Gross Unrealized Losses, 12 Months or Longer	20	34
Estimated Fair Value, Total	1,588	3,051
Gross Unrealized Losses, Total	20	57
Commercial mortgage-backed
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value, Less than 12 months	184	728
Gross Unrealized Losses, Less than 12 Months	2	10
Estimated Fair Value, 12 Months or Longer	236	397
Gross Unrealized Losses, 12 Months or Longer	5	22
Estimated Fair Value, Total	420	1,125
Gross Unrealized Losses, Total	7	32
Other asset-backed
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value, Less than 12 months	450	834
Gross Unrealized Losses, Less than 12 Months	10	21
Estimated Fair Value, 12 Months or Longer	95	125
Gross Unrealized Losses, 12 Months or Longer	2	3
Estimated Fair Value, Total	545	959
Gross Unrealized Losses, Total	12	24
Asset-backed
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value, Less than 12 months	728	3,494
Gross Unrealized Losses, Less than 12 Months	12	54
Estimated Fair Value, 12 Months or Longer	1,825	1,641
Gross Unrealized Losses, 12 Months or Longer	27	59
Estimated Fair Value, Total	2,553	5,135
Gross Unrealized Losses, Total	39	113
U.S. Treasury and obligations of government-sponsored enterprises
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value, Less than 12 months	48	21
Gross Unrealized Losses, Less than 12 Months	1	0
Estimated Fair Value, 12 Months or Longer	14	19
Gross Unrealized Losses, 12 Months or Longer	0	0
Estimated Fair Value, Total	62	40
Gross Unrealized Losses, Total	1	0
Foreign government
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value, Less than 12 months	32	114
Gross Unrealized Losses, Less than 12 Months	1	2
Estimated Fair Value, 12 Months or Longer	27	124
Gross Unrealized Losses, 12 Months or Longer	0	2
Estimated Fair Value, Total	59	238
Gross Unrealized Losses, Total	$ 1	$ 4

Investments (Activity related t

Investments (Activity related to the pretax fixed maturity credit loss component reflected within retained earnings for securities still held for which a portion of an OTTI loss was recognized in OCI) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Roll Forward]
Balance beginning of period	$ 18	$ 27
Reductions for securities sold during the period	(1)	(2)
Balance end of period	$ 17	$ 25

Investments (Contractual maturi

Investments (Contractual maturity) (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Investments [Abstract]
Due in one year or less, cost or amortized cost	$ 1,144	$ 1,350
Due after one year through five years, cost or amortized cost	7,718	7,979
Due after five years through ten years, cost or amortized cost	16,874	16,859
Due after ten years, cost or amortized cost	12,176	11,893
Cost or Amortized Cost	37,912	38,081
Due in one year or less, estimated fair value	1,155	1,359
Due after one year through five years, estimated fair value	7,992	8,139
Due after five years through ten years, estimated fair value	17,374	16,870
Due after ten years, estimated fair value	14,004	13,174
Total Estimated Fair Value	$ 40,525	$ 39,542

Fair Value (Assets and liabilit

Fair Value (Assets and liabilities measured at fair value on a recurring basis) (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Fixed maturity securities:
Debt securities	$ 40,553	$ 39,546
Equity securities:
Equity securities	814	780
Short term and other	1,379	1,165
Total assets	42,746	41,491
Liabilities
Other liabilities	2	(4)
Total liabilities	2	(4)
Corporate and other bonds
Fixed maturity securities:
Debt securities	21,163	19,814
States, municipalities and political subdivisions
Fixed maturity securities:
Debt securities	10,596	10,748
Asset-backed
Fixed maturity securities:
Debt securities	8,794	8,984
Common Stock
Equity securities:
Equity securities	140	148
Preferred stock
Equity securities:
Equity securities	674	632
Level 1
Fixed maturity securities:
Debt securities	203	196
Equity securities:
Equity securities	186	192
Short term and other	253	216
Total assets	642	604
Liabilities
Other liabilities	0	0
Total liabilities	0	0
Level 1 | Corporate and other bonds
Fixed maturity securities:
Debt securities	203	196
Level 1 | States, municipalities and political subdivisions
Fixed maturity securities:
Debt securities	0	0
Level 1 | Asset-backed
Fixed maturity securities:
Debt securities	0	0
Level 1 | Common Stock
Equity securities:
Equity securities	136	144
Level 1 | Preferred stock
Equity securities:
Equity securities	50	48
Level 2
Fixed maturity securities:
Debt securities	39,913	38,931
Equity securities:
Equity securities	608	570
Short term and other	1,126	949
Total assets	41,647	40,450
Liabilities
Other liabilities	2	(4)
Total liabilities	2	(4)
Level 2 | Corporate and other bonds
Fixed maturity securities:
Debt securities	20,707	19,396
Level 2 | States, municipalities and political subdivisions
Fixed maturity securities:
Debt securities	10,596	10,748
Level 2 | Asset-backed
Fixed maturity securities:
Debt securities	8,610	8,787
Level 2 | Common Stock
Equity securities:
Equity securities	0	0
Level 2 | Preferred stock
Equity securities:
Equity securities	608	570
Level 3
Fixed maturity securities:
Debt securities	437	419
Equity securities:
Equity securities	20	18
Short term and other	0	0
Total assets	457	437
Liabilities
Other liabilities	0	0
Total liabilities	0	0
Level 3 | Corporate and other bonds
Fixed maturity securities:
Debt securities	253	222
Level 3 | States, municipalities and political subdivisions
Fixed maturity securities:
Debt securities	0	0
Level 3 | Asset-backed
Fixed maturity securities:
Debt securities	184	197
Level 3 | Common Stock
Equity securities:
Equity securities	4	4
Level 3 | Preferred stock
Equity securities:
Equity securities	$ 16	$ 14

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
	Mar. 31, 2019	Mar. 31, 2018
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, Beginning, Assets	$ 437	$ 454
Total realized and unrealized investment gains (losses)	11	(5)
Total realized and unrealized investment gains (losses)	13	(1)
Purchases	76	30
Sales	0	(72)
Settlements	(6)	(8)
Transfers into Level 3	5	5
Transfers out of Level 3	(68)	(10)
Balance, Ending, Assets	457	398
Unrealized gains (losses) on Level 3 assets and liabilities held as of March 31, 2019 recognized in Net income (loss)	2	(2)
Unrealized gains (losses) on Level 3 assets and liabilities held as of March 31, 2019 recognized in Other comprehensive income (loss)	10
Corporate and other bonds
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, Beginning, Assets	222	98
Total realized and unrealized investment gains (losses)	8	0
Total realized and unrealized investment gains (losses)	8	(1)
Purchases	56	0
Sales	0	0
Settlements	(2)	(2)
Transfers into Level 3	0	5
Transfers out of Level 3	(31)	0
Balance, Ending, Assets	253	100
Unrealized gains (losses) on Level 3 assets and liabilities held as of March 31, 2019 recognized in Net income (loss)	0	0
Unrealized gains (losses) on Level 3 assets and liabilities held as of March 31, 2019 recognized in Other comprehensive income (loss)	7
States, municipalities and political subdivisions
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, Beginning, Assets	0	1
Total realized and unrealized investment gains (losses)	0	0
Total realized and unrealized investment gains (losses)	0	0
Purchases	0	0
Sales	0	0
Settlements	0	0
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Balance, Ending, Assets	0	1
Unrealized gains (losses) on Level 3 assets and liabilities held as of March 31, 2019 recognized in Net income (loss)	0	0
Unrealized gains (losses) on Level 3 assets and liabilities held as of March 31, 2019 recognized in Other comprehensive income (loss)	0
Asset-backed
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, Beginning, Assets	197	335
Total realized and unrealized investment gains (losses)	3	(5)
Total realized and unrealized investment gains (losses)	3	2
Purchases	20	30
Sales	0	(72)
Settlements	(4)	(6)
Transfers into Level 3	5	0
Transfers out of Level 3	(37)	(10)
Balance, Ending, Assets	184	279
Unrealized gains (losses) on Level 3 assets and liabilities held as of March 31, 2019 recognized in Net income (loss)	0	0
Unrealized gains (losses) on Level 3 assets and liabilities held as of March 31, 2019 recognized in Other comprehensive income (loss)	3
Equity securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, Beginning, Assets	18	20
Total realized and unrealized investment gains (losses)	0	0
Total realized and unrealized investment gains (losses)	2	(2)
Purchases	0	0
Sales	0	0
Settlements	0	0
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Balance, Ending, Assets	20	18
Unrealized gains (losses) on Level 3 assets and liabilities held as of March 31, 2019 recognized in Net income (loss)	2	(2)
Unrealized gains (losses) on Level 3 assets and liabilities held as of March 31, 2019 recognized in Other comprehensive income (loss)	0
Reported in Net investment gains (losses)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Reported in Other comprehensive income (loss)	2	4
Reported in Net investment gains (losses) | Corporate and other bonds
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Reported in Other comprehensive income (loss)	0	(1)
Reported in Net investment gains (losses) | States, municipalities and political subdivisions
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Reported in Other comprehensive income (loss)	0	0
Reported in Net investment gains (losses) | Asset-backed
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Reported in Other comprehensive income (loss)	0	7
Reported in Net investment gains (losses) | Equity securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Reported in Other comprehensive income (loss)	$ 2	$ (2)

Fair Value (Narrative) (Details

Fair Value (Narrative) (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Fair Value Disclosures [Abstract]
Other invested assets overseas deposit	$ 54	$ 48

Fair Value (Quantitative inform

Fair Value (Quantitative information about significant unobservable inputs in the fair value measurement of level 3 assets) (Details) $ in Millions	Mar. 31, 2019USD ($)	Dec. 31, 2018USD ($)
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Estimated fair value	$ 42,746	$ 41,491
Fixed maturity securities | Income Approach Valuation Technique
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Estimated fair value	$ 293	$ 228
Measurement Input, Credit Spread | Income Approach Valuation Technique | Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Debt securities, available-for-sale, measurement Input	0.01	0.01
Measurement Input, Credit Spread | Income Approach Valuation Technique | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Debt securities, available-for-sale, measurement Input	0.05	0.12
Measurement Input, Credit Spread | Income Approach Valuation Technique | Weighted Average
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Debt securities, available-for-sale, measurement Input	0.03	0.03

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	Mar. 31, 2019	Dec. 31, 2018
Financial Assets [Abstract]
Mortgage loans	$ 863	$ 839
Financial Liabilities [Abstract]
Long term debt	2,681	2,680
Carrying Amount
Financial Assets [Abstract]
Mortgage loans	863	839
Note receivable	20	35
Financial Liabilities [Abstract]
Long term debt	2,681	2,680
Estimated Fair Value
Financial Assets [Abstract]
Mortgage loans	868	827
Note receivable	20	35
Financial Liabilities [Abstract]
Long term debt	2,792	2,731
Level 1 | Estimated Fair Value
Financial Assets [Abstract]
Mortgage loans	0	0
Note receivable	0	0
Financial Liabilities [Abstract]
Long term debt	0	0
Level 2 | Estimated Fair Value
Financial Assets [Abstract]
Mortgage loans	0	0
Note receivable	0	0
Financial Liabilities [Abstract]
Long term debt	2,792	2,731
Level 3 | Estimated Fair Value
Financial Assets [Abstract]
Mortgage loans	868	827
Note receivable	20	35
Financial Liabilities [Abstract]
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
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018	Dec. 31, 2010
Liability for Claims and Claims Adjustment Expense [Line Items]
Catastrophe losses net of reinsurance	$ 58	$ 34
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 transferrred to NICO under A&EP Loss Portfolio Transfer				215
Total consideration paid to NICO under AEP Loss Portfolio Transfer				$ 2,200
Net A&EP adverse development before consideration of LPT	0	$ 113
Cumulative amounts ceded under AEP Loss Portfolio Transfer	3,100		$ 3,100
Deferred reinsurance benefit yet to be recognized	352		374
Fair value of collateral trust account established by NICO under A&EP Loss Portfolio Transfer	$ 3,000		$ 2,700

Claim and Claim Adjustment Ex_4

Claim and Claim Adjustment Expense Reserves (Reconciliation of claim and claim adjustment expense reserves) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Reserves, beginning of year: [Abstract]
Gross	$ 21,984	$ 22,004
Ceded	4,019	3,934
Net reserves, beginning of year	17,965	18,070
Net incurred claim and claim adjustment expenses:
Provision for insured events of current year	1,309	1,246
Increase (decrease) in provision for insured events of prior years	8	(34)
Amortization of discount	50	47
Total net incurred	1,367	1,259
Net payments attributable to:
Current year events	(100)	(91)
Prior year events	(1,309)	(1,219)
Total net payments	(1,409)	(1,310)
Foreign currency translation adjustment and other	13	(9)
Net reserves, end of period	17,936	18,010
Ceded reserves, end of period	3,900	4,057
Gross reserves, end of period	$ 21,836	$ 22,067

Claim and Claim Adjustment Ex_5

Claim and Claim Adjustment Expense Reserves (Net prior year development) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Segment Reporting Information [Line Items]
Pretax (favorable) unfavorable premium development, excluding Life & Group	$ (14)	$ (39)
Specialty
Segment Reporting Information [Line Items]
Pretax (favorable) unfavorable premium development, excluding Life & Group	(20)	(30)
Commercial
Segment Reporting Information [Line Items]
Pretax (favorable) unfavorable premium development, excluding Life & Group	(8)	(9)
International
Segment Reporting Information [Line Items]
Pretax (favorable) unfavorable premium development, excluding Life & Group	14	0
Corporate & Other
Segment Reporting Information [Line Items]
Pretax (favorable) unfavorable premium development, excluding Life & Group	$ 0	$ 0

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
	Mar. 31, 2019	Mar. 31, 2018
Liability for Claims and Claims Adjustment Expense [Line Items]
Medical Professional Liability	$ 15	$ 20
Other Professional Liability and Management Liability	(12)	(34)
Surety	(25)	(15)
Warranty	0	0
Other	2	(1)
Total pretax (favorable) unfavorable development	$ (20)	$ (30)

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
	Mar. 31, 2019	Mar. 31, 2018
Liability for Claims and Claims Adjustment Expense [Line Items]
Commercial Auto	$ (5)	$ (1)
General Liability	(20)	(8)
Workers' Compensation	2	(6)
Property and Other	15	6
Total pretax (favorable) unfavorable development	$ (8)	$ (9)

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
	Mar. 31, 2019	Mar. 31, 2018
Liability for Claims and Claims Adjustment Expense [Line Items]
Casualty	$ 0	$ 0
Property	15	(1)
Energy and Marine	(1)	0
Specialty	0	1
Total pretax (favorable) unfavorable development	$ 14	$ 0

Claim and Claim Adjustment Ex_9

Claim and Claim Adjustment Expense Reserves (Impact of Loss Portfolio Transfer on the Consolidated Statement of Operations) (Details) - Asbestos and Environmental Reserves - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Liability for Claims and Claims Adjustment Expense [Line Items]
Net A&EP adverse development before consideration of LPT	$ 0	$ 113
Provision for uncollectible third-party reinsurance on A&EP	0	(16)
Total additional amounts ceded under LPT	0	97
Retroactive reinsurance benefit recognized	(22)	(57)
Pretax impact of deferred retroactive reinsurance	$ (22)	$ 40

Legal Proceedings, Contingenc_2

Legal Proceedings, Contingencies and Guarantees (Narrative) (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Guarantee Obligations
Legal Proceedings, Commitments and Contingencies, and Guarantees [Line Items]
Guarantor obligations, maximum exposure, undiscounted	$ 1,700
Indemnification Agreement
Legal Proceedings, Commitments and Contingencies, and Guarantees [Line Items]
Guarantor obligations, maximum exposure, undiscounted	252
Guarantee agreement
Legal Proceedings, Commitments and Contingencies, and Guarantees [Line Items]
Guarantor obligations, maximum exposure, undiscounted	375
Guarantee and Indemnification
Legal Proceedings, Commitments and Contingencies, and Guarantees [Line Items]
Guarantor obligations, current carrying calue	$ 5	$ 5

Benefit Plans (Narrative) (Deta

Benefit Plans (Narrative) (Details) - Pension Benefits - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Total non-service cost (benefit) (less than)	$ (1)	$ (4)
Insurance Claims and Policyholder's Benefits, Including Policyholder's Dividends
Total non-service cost (benefit) (less than)	(1)	(1)
Other Expense
Total non-service cost (benefit) (less than)	$ (1)	$ (3)

Benefit Plans (Components of ne

Benefit Plans (Components of net periodic cost (benefit)) (Details) - Pension Benefits - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 0	$ 0
Interest cost on projected benefit obligation	25	23
Expected return on plan assets	(36)	(40)
Amortization of net actuarial (gain) loss	10	9
Settlement loss	0	4
Total non-service cost (benefit)	(1)	(4)
Total net periodic pension cost (benefit)	$ (1)	$ (4)

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
	Mar. 31, 2019	Mar. 31, 2018
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Total stockholder's equity at beginning of period	$ 11,217
Other comprehensive income (loss) before reclassifications	541	$ (412)
Amounts reclassified from accumulated other comprehensive income (loss) net of tax	(13)	4
Other comprehensive income (loss) after tax (expense) benefit	554	(416)
Total stockholder's equity at end of period	11,455	11,425
Reclassification from AOCI, tax	3	(1)
Tax (expense) benefit on other comprehensive income (loss)	(144)	108
Net unrealized gains (losses) on investments with OTTI losses
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Total stockholder's equity at beginning of period	16	30
Other comprehensive income (loss) before reclassifications	4	(10)
Amounts reclassified from accumulated other comprehensive income (loss) net of tax	0	(1)
Other comprehensive income (loss) after tax (expense) benefit	4	(9)
Total stockholder's equity at end of period	20	21
Reclassification from AOCI, tax	0	0
Tax (expense) benefit on other comprehensive income (loss)	(1)	2
Net unrealized gains (losses) on other investments
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Total stockholder's equity at beginning of period	61	859
Other comprehensive income (loss) before reclassifications	521	(414)
Amounts reclassified from accumulated other comprehensive income (loss) net of tax	(5)	15
Other comprehensive income (loss) after tax (expense) benefit	526	(429)
Total stockholder's equity at end of period	587	430
Reclassification from AOCI, tax	1	(4)
Tax (expense) benefit on other comprehensive income (loss)	(141)	109
Pension and postretirement benefits
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Total stockholder's equity at beginning of period	(775)	(775)
Other comprehensive income (loss) before reclassifications	(1)	0
Amounts reclassified from accumulated other comprehensive income (loss) net of tax	(8)	(10)
Other comprehensive income (loss) after tax (expense) benefit	7	10
Total stockholder's equity at end of period	(768)	(765)
Reclassification from AOCI, tax	2	3
Tax (expense) benefit on other comprehensive income (loss)	(2)	(3)
Cumulative foreign currency translation adjustment
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Total stockholder's equity at beginning of period	(180)	(98)
Other comprehensive income (loss) before reclassifications	17	12
Amounts reclassified from accumulated other comprehensive income (loss) net of tax	0	0
Other comprehensive income (loss) after tax (expense) benefit	17	12
Total stockholder's equity at end of period	(163)	(86)
Reclassification from AOCI, tax	0	0
Tax (expense) benefit on other comprehensive income (loss)	0	0
Accumulated other comprehensive income (loss)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Total stockholder's equity at beginning of period	(878)	16
Total stockholder's equity at end of period	$ (324)	$ (400)

Business Segments (Narrative) (

Business Segments (Narrative) (Details)	3 Months Ended
	Mar. 31, 2019segments
Core Segments - Specialty, Commercial and International
Segment Reporting Information [Line Items]
Number of operating segments	3
Non-Core Segments, Life & Group Non-Core and Corporate and Other Non-Core
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
	Mar. 31, 2019	Mar. 31, 2018
Operating revenues
Net earned premiums	$ 1,803	$ 1,785
Net investment income	571	490
Non-insurance warranty revenue	281	238
Other revenues	9	10
Total operating revenues	2,664	2,523
Claims, Benefits and Expenses
Net incurred claims and benefits	1,351	1,333
Policyholders’ dividends	6	6
Amortization of deferred acquisition costs	342	296
Non-insurance warranty expense	260	216
Other insurance related expenses	251	277
Other expenses	66	61
Total claims, benefits and expenses	2,276	2,189
Core income (loss) before income tax	388	334
Income tax (expense) benefit on core income (loss)	(70)	(53)
Core income (loss)	318	281
Net investment gains (losses)	31	12
Income tax (expense) benefit on net investment gains (losses)	(7)	(2)
Net investment gains (losses), after tax	24	10
Net income	342	291
Operating Segments | Specialty
Operating revenues
Net earned premiums	661	672
Net investment income	155	122
Non-insurance warranty revenue	281	238
Other revenues	1	1
Total operating revenues	1,098	1,033
Claims, Benefits and Expenses
Net incurred claims and benefits	392	379
Policyholders’ dividends	1	1
Amortization of deferred acquisition costs	147	145
Non-insurance warranty expense	260	216
Other insurance related expenses	70	64
Other expenses	12	11
Total claims, benefits and expenses	882	816
Core income (loss) before income tax	216	217
Income tax (expense) benefit on core income (loss)	(47)	(46)
Core income (loss)	169	171
Operating Segments | Commercial
Operating revenues
Net earned premiums	763	743
Net investment income	190	149
Non-insurance warranty revenue	0	0
Other revenues	7	8
Total operating revenues	960	900
Claims, Benefits and Expenses
Net incurred claims and benefits	510	468
Policyholders’ dividends	5	5
Amortization of deferred acquisition costs	127	121
Non-insurance warranty expense	0	0
Other insurance related expenses	130	127
Other expenses	11	11
Total claims, benefits and expenses	783	732
Core income (loss) before income tax	177	168
Income tax (expense) benefit on core income (loss)	(38)	(35)
Core income (loss)	139	133
Operating Segments | International
Operating revenues
Net earned premiums	250	236
Net investment income	15	14
Non-insurance warranty revenue	0	0
Other revenues	0	0
Total operating revenues	265	250
Claims, Benefits and Expenses
Net incurred claims and benefits	162	142
Policyholders’ dividends	0	0
Amortization of deferred acquisition costs	68	30
Non-insurance warranty expense	0	0
Other insurance related expenses	25	56
Other expenses	4	(4)
Total claims, benefits and expenses	259	224
Core income (loss) before income tax	6	26
Income tax (expense) benefit on core income (loss)	0	(3)
Core income (loss)	6	23
Operating Segments | Life & Group
Operating revenues
Net earned premiums	130	134
Net investment income	204	200
Non-insurance warranty revenue	0	0
Other revenues	1	1
Total operating revenues	335	335
Claims, Benefits and Expenses
Net incurred claims and benefits	308	303
Policyholders’ dividends	0	0
Amortization of deferred acquisition costs	0	0
Non-insurance warranty expense	0	0
Other insurance related expenses	28	30
Other expenses	2	2
Total claims, benefits and expenses	338	335
Core income (loss) before income tax	(3)	0
Income tax (expense) benefit on core income (loss)	13	14
Core income (loss)	10	14
Operating Segments | Corporate & Other
Operating revenues
Net earned premiums	0	0
Net investment income	7	5
Non-insurance warranty revenue	0	0
Other revenues	2	1
Total operating revenues	9	6
Claims, Benefits and Expenses
Net incurred claims and benefits	(21)	41
Policyholders’ dividends	0	0
Amortization of deferred acquisition costs	0	0
Non-insurance warranty expense	0	0
Other insurance related expenses	(1)	0
Other expenses	39	42
Total claims, benefits and expenses	17	83
Core income (loss) before income tax	(8)	(77)
Income tax (expense) benefit on core income (loss)	2	17
Core income (loss)	(6)	(60)
Eliminations
Operating revenues
Net earned premiums	(1)	0
Net investment income	0	0
Non-insurance warranty revenue	0	0
Other revenues	(2)	(1)
Total operating revenues	(3)	(1)
Claims, Benefits and Expenses
Net incurred claims and benefits	0	0
Policyholders’ dividends	0	0
Amortization of deferred acquisition costs	0	0
Non-insurance warranty expense	0	0
Other insurance related expenses	(1)	0
Other expenses	(2)	(1)
Total claims, benefits and expenses	(3)	(1)
Core income (loss) before income tax	0	0
Income tax (expense) benefit on core income (loss)	0	0
Core income (loss)	$ 0	$ 0

Business Segments (Balance Shee

Business Segments (Balance Sheet Information) (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Segment Reporting Information [Line Items]
Reinsurance receivables	$ 4,306	$ 4,455
Insurance receivables	2,476	2,365
Deferred acquisition costs	664	633
Goodwill	147	146
Deferred non-insurance warranty acquisition expense	2,576	2,513
Insurance reserves
Claim and claim adjustment expenses	21,836	21,984
Unearned premiums	4,422	4,183
Future policy benefits	11,078	10,597
Deferred non-insurance warranty revenue	3,472	3,402
Operating Segments | Specialty
Segment Reporting Information [Line Items]
Reinsurance receivables	674	649
Insurance receivables	933	947
Deferred acquisition costs	315	308
Goodwill	117	117
Deferred non-insurance warranty acquisition expense	2,576	2,513
Insurance reserves
Claim and claim adjustment expenses	5,470	5,465
Unearned premiums	2,201	2,132
Future policy benefits	0	0
Deferred non-insurance warranty revenue	3,472	3,402
Operating Segments | Commercial
Segment Reporting Information [Line Items]
Reinsurance receivables	761	795
Insurance receivables	1,234	1,277
Deferred acquisition costs	247	230
Goodwill	0	0
Deferred non-insurance warranty acquisition expense	0	0
Insurance reserves
Claim and claim adjustment expenses	8,623	8,743
Unearned premiums	1,553	1,454
Future policy benefits	0	0
Deferred non-insurance warranty revenue	0	0
Operating Segments | International
Segment Reporting Information [Line Items]
Reinsurance receivables	237	250
Insurance receivables	302	284
Deferred acquisition costs	102	95
Goodwill	30	29
Deferred non-insurance warranty acquisition expense	0	0
Insurance reserves
Claim and claim adjustment expenses	1,787	1,750
Unearned premiums	528	475
Future policy benefits	0	0
Deferred non-insurance warranty revenue	0	0
Operating Segments | Life & Group
Segment Reporting Information [Line Items]
Reinsurance receivables	408	414
Insurance receivables	7	9
Deferred acquisition costs	0	0
Goodwill	0	0
Deferred non-insurance warranty acquisition expense	0	0
Insurance reserves
Claim and claim adjustment expenses	3,645	3,601
Unearned premiums	142	122
Future policy benefits	11,078	10,597
Deferred non-insurance warranty revenue	0	0
Operating Segments | Corporate & Other
Segment Reporting Information [Line Items]
Reinsurance receivables	2,226	2,347
Insurance receivables	0	(152)
Deferred acquisition costs	0	0
Goodwill	0	0
Deferred non-insurance warranty acquisition expense	0	0
Insurance reserves
Claim and claim adjustment expenses	2,311	2,425
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	(2)	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
	Mar. 31, 2019	Mar. 31, 2018
Revenues	$ 2,695	$ 2,535
Net investment gains (losses)	31	12
Operating Segments | Specialty
Revenues	1,098	1,033
Operating Segments | Commercial
Revenues	960	900
Operating Segments | International
Revenues	265	250
Operating Segments | Life & Group
Revenues	335	335
Operating Segments | Corporate & Other
Revenues	9	6
Eliminations
Revenues	(3)	(1)
Total operating revenues
Revenues	2,664	2,523
Management & Professional Liability | Operating Segments | Specialty
Revenues	636	624
Surety | Operating Segments | Specialty
Revenues	139	129
Warranty & Alternative Risks | Operating Segments | Specialty
Revenues	323	280
Middle Market | Operating Segments | Commercial
Revenues	547	504
Small Business | Operating Segments | Commercial
Revenues	121	119
Other Commercial Insurance | Operating Segments | Commercial
Revenues	292	277
Canada | Operating Segments | International
Revenues	66	58
Europe | Operating Segments | International
Revenues	91	88
Hardy | Operating Segments | International
Revenues	$ 108	$ 104

Non-Insurance Revenues from C_2

Non-Insurance Revenues from Contracts with Customers (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Revenue from Contract with Customer [Abstract]
Deferred non-insurance warranty revenue	$ 3,472		$ 3,402
Contract with customer, liability, revenue recognized	$ 265	$ 222

Non-Insurance Revenues from C_3

Non-Insurance Revenues from Contracts with Customers (Performance Obligation) (Details) $ in Millions	Mar. 31, 2019USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-04-01
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Remaining performance obligation, amount	$ 754
Remaining performance obligation, expected timing of satisfaction, period	9 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-01-01
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Remaining performance obligation, amount	$ 852
Remaining performance obligation, expected timing of satisfaction, period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Remaining performance obligation, amount	$ 673
Remaining performance obligation, expected timing of satisfaction, period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Remaining performance obligation, amount	$ 1,200
Remaining performance obligation, expected timing of satisfaction, period

Leases (Narrative) (Details)

Leases (Narrative) (Details) $ in Millions	3 Months Ended
	Mar. 31, 2019USD ($)
Leases [Abstract]
Operating lease cost	$ 10
Variable lease cost	4
Operating lease payments	$ 8

Leases (Assets and Liabilities)

Leases (Assets and Liabilities) (Details) $ in Millions	Mar. 31, 2019USD ($)
Leases [Abstract]
Operating lease ROU assets	$ 233
Operating lease liabilities	$ 308

Leases (Maturities of Operating

Leases (Maturities of Operating Lease Liabilities) (Details) $ in Millions	Mar. 31, 2019USD ($)
Leases [Abstract]
2019 (Excluding the three months ended March 31, 2019)	$ 24
2020	40
2021	42
2022	39
2023	33
Thereafter	202
Total lease payments	380
Less: Discount	(72)
Total operating lease liabilities	$ 308

Leases (Lease Terms and Discont

Leases (Lease Terms and Discont Rates) (Details)	Mar. 31, 2019
Leases [Abstract]
Weighted average remaining lease term	3.40%
Weighted average discount rate	11 years

Leases (Minimum Lease Payments)

Leases (Minimum Lease Payments) (Details) $ in Millions	Dec. 31, 2018USD ($)
Leases [Abstract]
2019	$ 35
2020	39
2021	41
2022	38
2023	32
Thereafter	200
Total	$ 385