Cincinnati Financial (CINF) 10-Q 24 Apr 19 2019 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2019	Apr. 19, 2019
Document Documentand Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2019
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q1
Trading Symbol	CINF
Entity Registrant Name	CINCINNATI FINANCIAL CORP
Entity Central Index Key	0000020286
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		163,229,828

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Investments
Fixed maturities, at fair value (amortized cost: 2019—$10,734; 2018—$10,643)	$ 11,022	$ 10,689
Equity securities, at fair value (cost: 2019—$3,381; 2018—$3,368)	6,571	5,920
Other invested assets	271	123
Total investments	17,864	16,732
Cash and cash equivalents	802	784
Investment income receivable	128	132
Finance receivable	72	71
Premiums receivable	1,785	1,644
Reinsurance recoverable	527	484
Prepaid reinsurance premiums	50	44
Deferred policy acquisition costs	751	738
Land, building and equipment, net, for company use (accumulated depreciation: 2019—$265; 2018—$265)	202	195
Other assets	340	308
Separate accounts	831	803
Total assets	23,352	21,935
Insurance reserves
Loss and loss expense reserves	5,944	5,707
Life policy and investment contract reserves	2,784	2,779
Unearned premiums	2,717	2,516
Other liabilities	752	804
Deferred income tax	817	627
Note payable	32	32
Long-term debt and lease obligations	845	834
Separate accounts	831	803
Total liabilities	14,722	14,102
Commitments and contingent liabilities (Note 12)
Shareholders' Equity
Common stock, par value—$2 per share; (authorized: 2019 and 2018—500 million shares; issued: 2019 and 2018—198.3 million shares)	397	397
Paid-in capital	1,277	1,281
Retained earnings	8,229	7,625
Accumulated other comprehensive income	210	22
Treasury stock at cost (2019—35.1 million shares and 2018—35.5 million shares)	(1,483)	(1,492)
Total shareholders' equity	8,630	7,833
Total liabilities and shareholders' equity	$ 23,352	$ 21,935

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) shares in Millions, $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Statement of Financial Position [Abstract]
Fixed maturities, amortized cost	$ 10,734	$ 10,643
Available-for-sale Equity Securities, Amortized Cost Basis	3,381	3,368
Land, building and equipment, accumulated depreciation	$ 265	$ 265
Common stock, par value	$ 2	$ 2
Common stock, authorized	500	500
Common stock, issued	198.3	198.3
Common stock, outstanding	198.3	198.3
Treasury stock, shares	35.1	35.5

Condensed Consolidated Statemen

Condensed Consolidated Statements of Income - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Revenues
Earned premiums	$ 1,333	$ 1,260
Investment income, net of expenses	157	150
Investment gains and losses, net	663	(191)
Fee revenues	4	4
Other revenues	2	1
Total revenues	2,159	1,224
Benefits and Expenses
Insurance losses and contract holders' benefits	860	854
Underwriting, acquisition and insurance expenses	411	403
Interest expense	13	13
Other operating expenses	8	4
Total benefits and expenses	1,292	1,274
Income (Loss) Before Income Taxes	867	(50)
Provision (Benefit) for Income Taxes
Current	28	28
Deferred	144	(47)
Total provision (benefit) for income taxes	172	(19)
Net Income (Loss)	$ 695	$ (31)
Per Common Share
Net income (loss)—basic	$ 4.27	$ (0.19)
Net income (loss)—diluted	$ 4.22	$ (0.19)

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Net Income (Loss)	$ 695	$ (31)
Change in unrealized gains on investments, net of tax (benefit) of $50 and ($46), respectively	192	(175)
Amortization of pension actuarial loss and prior service cost, net of tax of $0 and $0, respectively	0	0
Change in life deferred acquisition costs, life policy reserves and other, net of tax (benefit) of $(1) and $1, respectively	(4)	5
Other comprehensive income (loss)	188	(170)
Comprehensive Income (Loss)	$ 883	$ (201)

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Comprehensive Income (Parenthetical) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Statement of Comprehensive Income [Abstract]
Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, Tax	$ 50	$ (46)
Other Comprehensive Income Loss, Pension And Other Postretirement Benefit Plans, Net Actuarial Loss And Prior Service Cost Arising During Period, Tax	0	0
Other Comprehensive Income, Change in Life Deferred Acquisition Costs, Life Policy Reserves and Other, Tax	$ (1)	$ 1

Condensed Consolidated Statem_4

Condensed Consolidated Statements of Shareholders' Equity - USD ($) shares in Millions, $ in Millions	Total	Common equities	Paid-In Capital	Retained Earnings	Accumulated Other Comprehensive Income	Treasury Stock
Unrealized gains reclassified to retained earnings for ASU 2016-01, after tax				$ 2,503	$ (2,503)
Beginning Balance (Previously Reported) at Dec. 31, 2017				5,180	2,788
Beginning Balance at Dec. 31, 2017		$ 397	$ 1,265	7,683	285	$ (1,387)
Share-based awards		0	(17)			14
Share-based compensation			9
Other			1			1
Net Income (Loss)	$ (31)			(31)
Dividends declared				(87)
Other comprehensive income (loss)	(170)				(170)
Shares acquired - share repurchase authorization						(15)
Shares acquired - share-based compensation plans						(2)
Ending Balance at Mar. 31, 2018	7,946	$ 397	1,258	7,565	115	(1,389)
Beginning Balance (in shares) at Dec. 31, 2017		163.9
Share-based awards (in shares)		0.4
Shares acquired - share repurchase authorization (in shares)		(0.2)
Ending Balance (in shares) at Mar. 31, 2018		164.1
Unrealized gains reclassified to retained earnings for ASU 2016-01, after tax					0
Beginning Balance (Previously Reported) at Dec. 31, 2018				7,625	22
Beginning Balance at Dec. 31, 2018	7,833	$ 397	1,281	7,625	22	(1,492)
Share-based awards		0	(14)			13
Share-based compensation			9
Other			1			1
Net Income (Loss)	695			695
Dividends declared				(91)
Other comprehensive income (loss)	188				188
Shares acquired - share repurchase authorization						0
Shares acquired - share-based compensation plans						(5)
Ending Balance at Mar. 31, 2019	$ 8,630	$ 397	$ 1,277	8,229	210	$ (1,483)
Beginning Balance (in shares) at Dec. 31, 2018	198.3	162.8
Share-based awards (in shares)		0.4
Shares acquired - share repurchase authorization (in shares)		0
Ending Balance (in shares) at Mar. 31, 2019	198.3	163.2
Unrealized gains reclassified to retained earnings for ASU 2016-01, after tax				$ 0	$ 0

Condensed Consolidated Statem_5

Condensed Consolidated Statements of Shareholders' Equity (Parenthetical) - $ / shares	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Statement of Stockholders' Equity [Abstract]
Dividends declared (in USD per share)	$ 0.56	$ 0.53

Condensed Consolidated Statem_6

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Cash Flows From Operating Activities
Net Income (Loss)	$ 695	$ (31)
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	19	18
Gain (Loss) on Sale of Investments	(660)	191
Share-based compensation	9	9
Interest credited to contract holders'	11	11
Deferred income tax expense	144	(47)
Changes in:
Investment income receivable	4	10
Premiums and reinsurance receivable	(95)	(26)
Deferred policy acquisition costs	(24)	(10)
Other assets	(25)	(8)
Loss and loss expense reserves	(40)	72
Life policy and investment contract reserves	22	21
Unearned premiums	113	55
Other liabilities	(93)	(137)
Current income tax receivable/payable	120	26
Net cash provided by operating activities	200	154
Cash Flows From Investing Activities
Sale of fixed maturities	1	5
Call or maturity of fixed maturities	269	393
Sale of equity securities	31	104
Purchase of fixed maturities	(289)	(438)
Purchase of equity securities	(26)	(110)
Investment in finance receivables	(8)	(6)
Collection of finance receivables	7	6
Investment in buildings and equipment	(5)	(3)
Change in other invested assets, net	(36)	(5)
Net cash used in investing activities	(56)	(54)
Cash Flows From Financing Activities
Payment of cash dividends to shareholders	(85)	(80)
Shares acquired - share repurchase authorization	0	(15)
Proceeds from stock options exercised	3	4
Contract holders' funds deposited	19	21
Contract holders' funds withdrawn	(44)	(46)
Other	(19)	(37)
Net cash used in financing activities	(126)	(153)
Net change in cash and cash equivalents	18	(53)
Cash and cash equivalents at beginning of year	784	657
Cash and cash equivalents at end of period	802	604
Supplemental Disclosures of Cash Flow Information:
Income taxes received	94	0
Noncash Activities
Conversion of securities	0	3
Equipment acquired under capital lease obligations	3	5
Cashless exercise of stock options	5	2
Other assets and other liabilities	$ 23	$ 30

Accounting Policies

Accounting Policies	3 Months Ended
	Mar. 31, 2019
Accounting Policies [Abstract]
Accounting Policies	NOTE 1 — Accounting Policies The condensed consolidated financial statements include the accounts of Cincinnati Financial Corporation and its consolidated subsidiaries, each of which is wholly owned. These statements are presented in conformity with accounting principles generally accepted in the United States of America (GAAP). Effective February 28, 2019, the company acquired MSP Underwriting Limited (MSP), a London-based global specialty underwriter. Refer to Note 14, Acquisition, for additional information. The interim condensed consolidated financial statements include MSP’s results for the period from February 28, 2019, through March 31, 2019. Foreign exchange rates related to MSP's operations did not have a material impact to our condensed consolidated financial statements. All intercompany balances and transactions have been eliminated in consolidation. The preparation of financial statements in conformity with GAAP requires us to make estimates and assumptions that affect amounts reported in the financial statements and accompanying notes. Our actual results could differ from those estimates. Certain financial information that is normally included in annual financial statements prepared in accordance with GAAP, but that is not required for interim reporting purposes, has been condensed or omitted. Our March 31, 2019 , condensed consolidated financial statements are unaudited. We believe that we have made all adjustments, consisting only of normal recurring accruals, that are necessary for fair presentation. These condensed consolidated financial statements should be read in conjunction with our consolidated financial statements included in our 2018 Annual Report on Form 10-K. The results of operations for interim periods do not necessarily indicate results to be expected for the full year. Adopted Accounting Updates ASU 2016-02, Leases (Topic 842) In February 2016, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) 2016-02, Leases (Topic 842). The main provision of ASU 2016-02 requires the recognition of lease assets and lease liabilities by lessees for those leases classified as operating leases under previous GAAP. The effective date of ASU 2016-02 is for interim and annual reporting periods beginning after December 15, 2018. In July 2018, the FASB issued ASU 2018-10, Codification Improvements to Topic 842 and ASU 2018-11, Targeted Improvements to Topic 842 . ASU 2018-10 makes narrow-scope amendments to certain aspects of the new leasing standard while ASU 2018-11 provides relief from costs of implementing certain aspects of the new leasing standard. The company adopted this ASU effective January 1, 2019, and it did not have a material impact on our company’s consolidated financial position, cash flows or results of operations. The company has elected the practical expedient package for carrying forward historical lease classifications, not re-evaluating for embedded leases and not reassessing initial direct costs. The company also elected additional practical expedients to not recognize short-term leases on the balance sheet and to only combine lease and nonlease components for certain asset classes. We also elected not to restate prior periods. In support of its insurance operations, the company leases real estate properties which qualify as operating leases and also leases equipment and autos which qualify as finance leases. The lease term for real estate properties is typically five years while the term for equipment and autos is three to six years. ASU 2017-08, Receivables - Nonrefundable Fees and Other Costs (Subtopic 310-20): Premium Amortization on Purchased Callable Debt Securities In March 2017, the FASB issued ASU 2017-08, Receivables - Nonrefundable Fees and Other Costs (Subtopic 310-20): Premium Amortization on Purchased Callable Debt Securities. ASU 2017-08 amends guidance on the amortization period of premiums on certain purchased callable debt securities. The amendments shorten the amortization period of premiums on certain purchased callable debt securities to the earliest call date. The amendments should be applied on a modified retrospective basis through a cumulative-effect adjustment to beginning retained earnings. The effective date of ASU 2017-08 is for interim and annual reporting periods beginning after December 15, 2018. The company adopted this ASU effective January 1, 2019, and it did not have a material impact on our company's consolidated financial position, cash flows or results of operations. ASU 2018-07, Compensation - Stock Compensation (Topic 718) - Improvements to Nonemployee Share-Based Payment Accounting In June 2018, the FASB issued ASU 2018-07, Compensation - Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting . ASU 2018-07 expands the scope of Topic 718, Compensation - Stock Compensation, which currently only includes share-based payments issued to employees, to include share-based payments issued to nonemployees for the acquisition of goods and services. The effective date of ASU 2018-07 is for interim and annual reporting periods beginning after December 15, 2018. The company adopted this ASU effective January 1, 2019, and it did not have a material impact on our company's consolidated financial position, cash flows or results of operations. Pending Accounting Updates ASU 2016-13, Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments In June 2016, the FASB issued ASU 2016-13, Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments . ASU 2016-13 amends previous guidance on the impairment of financial instruments by adding an impairment model that allows an entity to recognize expected credit losses as an allowance rather than impairing as they are incurred. The new guidance is intended to reduce complexity of credit impairment models and result in a more timely recognition of expected credit losses. The effective date of ASU 2016-13 is for interim and annual reporting periods beginning after December 15, 2019. The ASU has not yet been adopted. Management is currently evaluating the impact on our company's consolidated financial position, cash flows and results of operations. ASU 2017-04, Intangibles - Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment In January 2017, the FASB issued ASU 2017-04, Intangibles - Goodwill and Other (Topic 350) - Simplifying the Test for Goodwill Impairment . ASU 2017-04 simplifies the subsequent measurement of goodwill by eliminating Step 2 from the goodwill impairment test. Instead, an entity should perform its goodwill impairment test by comparing the fair value of a reporting unit with its carrying amount and recognize an impairment charge for the amount by which the carrying amount exceeds the reporting unit's fair value. The loss recognized should not exceed the total amount of goodwill allocated to that reporting unit and income tax effects from any tax deductible goodwill on the carrying amount of the reporting unit should be considered. The effective date of ASU 2017-04 is for interim and annual goodwill impairment tests performed in any fiscal years beginning after December 15, 2019. The ASU has not yet been adopted; however, it is not expected to have a material impact on our company's consolidated financial position, cash flows or results of operations. ASU 2018-12, Financial Services - Insurance (Topic 944): Targeted Improvements to the Accounting for Long-Duration Contracts In August 2018, the FASB issued ASU 2018-12, Financial Services - Insurance (Topic 944): Targeted Improvements to the Accounting for Long-Duration Contracts . ASU 2018-12 is intended to improve the timeliness of recognizing changes in the liability for future policy benefits and modify the rate used to discount future cash flows. The ASU will simplify and improve the accounting for certain market-based options or guarantees associated with deposit or account balance contracts, simplify amortization of deferred acquisition costs while improving and expanding required disclosures. The effective date of ASU 2018-12 is for interim and annual reporting periods beginning after December 15, 2020. The ASU has not yet been adopted. Management is currently evaluating the impact on our company's consolidated financial position, cash flows and results of operations. ASU 2018-13, Fair Value Measurement (Topic 820): Disclosure Framework - Changes to the Disclosure Requirements for Fair Value Measurement In August 2018, the FASB issued ASU 2018-13, Fair Value Measurement (Topic 820): Disclosure Framework - Changes to the Disclosure Requirements for Fair Value Measurement . ASU 2018-13 clarifies the fair value measurement disclosure requirements of ASC 820 by adding, eliminating and modifying disclosures. The effective date of ASU 2018-13 is for interim and annual reporting periods beginning after December 15, 2019. The ASU has not yet been adopted; however, it is not expected to have a material impact on our company's consolidated financial position, cash flows or results of operations. ASU 2018-14, Compensation - Retirement Benefits - Defined Benefit Plans - General (Topic 715-20): Disclosure Framework - Changes to the Disclosure Requirements for Defined Benefit Plans In August 2018, the FASB issued ASU 2018-14, Compensation - Retirement Benefits - Defined Benefit Plans - General (Topic 715-20): Disclosure Framework - Changes to the Disclosure Requirements for Defined Benefit Plans . ASU 2018-14 clarifies the guidance in ASC 715 to add, remove, and clarify disclosure requirements related to defined benefit pension and other postretirement plans. The effective date of ASU 2018-14 is for annual reporting periods ending after December 15, 2020. The ASU has not yet been adopted; however, it is not expected to have a material impact on our company's consolidated financial position, cash flows or results of operations. ASU 2018-15, Customer's Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract In August 2018, the FASB issued ASU 2018-15, Customer's Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract . ASU 2018-15 amends ASC 350 to include implementation costs of a cloud computing arrangement that is a service contract and clarifies that a customer should apply ASC 350-40 to determine which implementation costs should be capitalized in a cloud computing arrangement that is considered a service contract. The effective date of ASU 2018-15 is for interim and annual reporting periods beginning after December 15, 2019. The ASU has not yet been adopted. Management is currently evaluating the impact on our company's consolidated financial position, cash flows and results of operations.

Investments

Investments	3 Months Ended
	Mar. 31, 2019
Investments [Abstract]
Investments	Investments The following table provides cost or amortized cost, gross unrealized gains, gross unrealized losses and fair value for our fixed-maturity securities: (Dollars in millions) Cost or amortized cost Gross unrealized Fair value At March 31, 2019 gains losses Fixed maturity securities: Corporate $ 5,753 $ 160 $ 25 $ 5,888 States, municipalities and political subdivisions 4,269 153 3 4,419 Government-sponsored enterprises 305 — 3 302 Commercial mortgage-backed 292 6 1 297 United States government 99 1 — 100 Foreign government 16 — — 16 Total $ 10,734 $ 320 $ 32 $ 11,022 At December 31, 2018 Fixed maturity securities: Corporate $ 5,712 $ 85 $ 87 $ 5,710 States, municipalities and political subdivisions 4,251 84 31 4,304 Government-sponsored enterprises 316 1 7 310 Commercial mortgage-backed 287 3 2 288 United States government 67 1 1 67 Foreign government 10 — — 10 Total $ 10,643 $ 174 $ 128 $ 10,689 The net unrealized investment gains in our fixed-maturity portfolio at March 31, 2019 , are primarily the result of the continued low interest rate environment that increased the fair value of our fixed-maturity portfolio. Our commercial mortgage-backed securities had an average rating of Aa1/AA at March 31, 2019 , and December 31, 2018 . At March 31, 2019, Microsoft Corporation (Nasdaq:MSFT) was our largest single equity holding with a fair value of $296 million , which was 4.6 % of our publicly traded common equities portfolio and 1.7 % of the total investment portfolio. The table below provides fair values and gross unrealized losses by investment category and by the duration of the securities’ continuous unrealized loss positions: (Dollars in millions) Less than 12 months 12 months or more Total At March 31, 2019 Fair value Unrealized losses Fair value Unrealized losses Fair value Unrealized losses Fixed maturity securities: Corporate $ 343 $ 5 $ 685 $ 20 $ 1,028 $ 25 States, municipalities and political subdivisions 10 — 237 3 247 3 Government-sponsored enterprises 7 — 204 3 211 3 Commercial mortgage-backed securities 2 — 45 1 47 1 United States government — — 23 — 23 — Total $ 362 $ 5 $ 1,194 $ 27 $ 1,556 $ 32 At December 31, 2018 Fixed maturity securities: Corporate $ 2,082 $ 51 $ 501 $ 36 $ 2,583 $ 87 States, municipalities and political subdivisions 823 18 340 13 1,163 31 Government-sponsored enterprises 49 1 211 6 260 7 Commercial mortgage-backed 77 — 64 2 141 2 United States government — — 33 1 33 1 Total $ 3,031 $ 70 $ 1,149 $ 58 $ 4,180 $ 128 Contractual maturity dates for fixed-maturities investments were: (Dollars in millions) Amortized cost Fair value % of fair value At March 31, 2019 Maturity dates: Due in one year or less $ 598 $ 604 5.5 % Due after one year through five years 2,977 3,039 27.6 Due after five years through ten years 3,656 3,742 33.9 Due after ten years 3,503 3,637 33.0 Total $ 10,734 $ 11,022 100.0 % Actual maturities may differ from contractual maturities when there is a right to call or prepay obligations with or without call or prepayment penalties. The following table provides investment income and investment gains and losses, net: (Dollars in millions) Three months ended March 31, 2019 2018 Investment income: Interest $ 111 $ 110 Dividends 46 42 Other 3 1 Total 160 153 Less investment expenses 3 3 Total $ 157 $ 150 Investment gains and losses, net: Equity securities: Investment gains and losses on securities sold, net $ 4 $ 3 Unrealized gains and losses on securities still held, net 652 (198 ) Subtotal 656 (195 ) Fixed maturities: Gross realized gains 2 4 Subtotal 2 4 Other 5 — Total $ 663 $ (191 ) During the three months ended March 31, 2019 and 2018 , there were no fixed-maturity securities other-than-temporarily impaired. There were no credit losses on fixed-maturity securities for which a portion of other-than-temporary impairment (OTTI) has been recognized in other comprehensive income for the three months ended March 31, 2019 and 2018 . At March 31, 2019 , 358 fixed-maturity securities with a total unrealized loss of $27 million had been in an unrealized loss position for 12 months or more. Of that total, no fixed-maturity security had a fair value below 70% of amortized cost. At December 31, 2018 , 400 fixed-maturity securities with a total unrealized loss of $58 million had been in an unrealized loss position for 12 months or more. Of that total, no fixed-maturity securities had fair values below 70% of amortized cost.

Fair Value Measurements

Fair Value Measurements	3 Months Ended
	Mar. 31, 2019
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements In accordance with accounting guidance for fair value measurements and disclosures, we categorized our financial instruments, based on the priority of the observable and market-based data for the valuation technique used, into a three-level fair value hierarchy. The fair value hierarchy gives the highest priority to quoted prices with readily available independent data in active markets for identical assets or liabilities (Level 1) and the lowest priority to unobservable market inputs (Level 3). When various inputs for measurement fall within different levels of the fair value hierarchy, the lowest observable input that has a significant impact on fair value measurement is used. Our valuation techniques have not changed from those used at December 31, 2018 , and ultimately management determines fair value. See our 2018 Annual Report on Form 10-K, Item 8, Note 3, Fair Value Measurements, Page 141, for information on characteristics and valuation techniques used in determining fair value. Fair Value Disclosures for Assets The following tables illustrate the fair value hierarchy for those assets measured at fair value on a recurring basis at March 31, 2019 , and December 31, 2018 . We do not have any liabilities carried at fair value. There were no transfers between Level 1 and Level 2. (Dollars in millions) Quoted prices in active markets for identical assets (Level 1) Significant other observable inputs (Level 2) Significant unobservable inputs (Level 3) Total At March 31, 2019 Fixed maturities, available for sale: Corporate $ — $ 5,887 $ 1 $ 5,888 States, municipalities and political subdivisions — 4,415 4 4,419 Government-sponsored enterprises — 302 — 302 Commercial mortgage-backed — 297 — 297 United States government 100 — — 100 Foreign government — 16 — 16 Subtotal 100 10,917 5 11,022 Common equities 6,381 — — 6,381 Nonredeemable preferred equities — 190 — 190 Separate accounts taxable fixed maturities — 820 — 820 Top Hat savings plan mutual funds and common 38 — — 38 Total $ 6,519 $ 11,927 $ 5 $ 18,451 At December 31, 2018 Fixed maturities, available for sale: Corporate $ — $ 5,709 $ 1 $ 5,710 States, municipalities and political subdivisions — 4,300 4 4,304 Government-sponsored enterprises — 310 — 310 Commercial mortgage-backed — 288 — 288 United States government 67 — — 67 Foreign government — 10 — 10 Subtotal 67 10,617 5 10,689 Common equities 5,742 — — 5,742 Nonredeemable preferred equities — 178 — 178 Separate accounts taxable fixed maturities — 791 — 791 Top Hat savings plan mutual funds and common equity (included in Other assets) 34 — — 34 Total $ 5,843 $ 11,586 $ 5 $ 17,434 Each financial instrument that was deemed to have significant unobservable inputs when determining valuation is identified in the following tables by security type with a summary of changes in fair value as of March 31, 2019 . Total Level 3 assets continue to be less than 1% of financial assets measured at fair value in the condensed consolidated balance sheets. Assets presented in the table below were valued based primarily on broker/dealer quotes for which there is a lack of transparency as to inputs used to develop the valuations. Transfers out of Level 3 included situations where a broker quote was used without observable inputs or data that could be corroborated by our pricing vendors in the prior period and significant other observable inputs were identified in the current period. The quantitative detail of these unobservable inputs is neither provided nor reasonably available to us. The following table provides the change in Level 3 assets for the three months ended March 31 : (Dollars in millions) Asset fair value measurements using significant unobservable inputs Corporate fixed maturities States, Total Beginning balance, January 1, 2019 $ 1 $ 4 $ 5 Total gains or losses (realized/unrealized): Included in net income — — — Included in other comprehensive income — — — Purchases — — — Sales — — — Transfers into Level 3 — — — Transfers out of Level 3 — — — Ending balance, March 31, 2019 $ 1 $ 4 $ 5 Beginning balance, January 1, 2018 $ 1 $ 5 $ 6 Total gains or losses (realized/unrealized): Included in net income (loss) — — — Included in other comprehensive income (loss) — (1 ) (1 ) Purchases — — — Sales — — — Transfers into Level 3 — — — Transfers out of Level 3 — — — Ending balance, March 31, 2018 $ 1 $ 4 $ 5 With the exception of the above tables, additional disclosures for the Level 3 category are not material and therefore not provided. Fair Value Disclosures for Assets and Liabilities Not Carried at Fair Value The disclosures below are presented to provide information about the effects of current market conditions on financial instruments that are not reported at fair value in our condensed consolidated financial statements. This table summarizes the book value and principal amounts of our long-term debt: (Dollars in millions) Book value Principal amount Interest rate Year of issue March 31, December 31, March 31, December 31, 2019 2018 2019 2018 6.900 % 1998 Senior debentures, due 2028 $ 27 $ 27 $ 28 $ 28 6.920 % 2005 Senior debentures, due 2028 391 391 391 391 6.125 % 2004 Senior notes, due 2034 370 370 374 374 Total $ 788 $ 788 $ 793 $ 793 The following table shows fair values of our note payable and long-term debt: (Dollars in millions) Quoted prices in active markets for identical assets (Level 1) Significant other observable inputs (Level 2) Significant unobservable inputs (Level 3) Total At March 31, 2019 Note payable $ — $ 32 $ — $ 32 6.900% senior debentures, due 2028 — 33 — 33 6.920% senior debentures, due 2028 — 486 — 486 6.125% senior notes, due 2034 — 459 — 459 Total $ — $ 1,010 $ — $ 1,010 At December 31, 2018 Note payable $ — $ 32 $ — $ 32 6.900% senior debentures, due 2028 — 32 — 32 6.920% senior debentures, due 2028 — 471 — 471 6.125% senior notes, due 2034 — 440 — 440 Total $ — $ 975 $ — $ 975 The following table shows the fair value of our life policy loans included in other invested assets and the fair values of our deferred annuities and structured settlements included in life policy and investment contract reserves: (Dollars in millions) Quoted prices in active markets for identical assets (Level 1) Significant other observable inputs (Level 2) Significant unobservable inputs (Level 3) Total At March 31, 2019 Life policy loans $ — $ — $ 41 $ 41 Deferred annuities — — 751 751 Structured settlements — 195 — 195 Total $ — $ 195 $ 751 $ 946 At December 31, 2018 Life policy loans $ — $ — $ 40 $ 40 Deferred annuities — — 742 742 Structured settlements — 185 — 185 Total $ — $ 185 $ 742 $ 927 Outstanding principal and interest for these life policy loans totaled $32 million and $33 million at March 31, 2019 , and December 31, 2018 , respectively. Recorded reserves for the deferred annuities were $776 million and $787 million at March 31, 2019 , and December 31, 2018 , respectively. Recorded reserves for the structured settlements were $154 million and $156 million at March 31, 2019 , and December 31, 2018 , respectively.

Property Casualty Loss and Loss

Property Casualty Loss and Loss Expenses	3 Months Ended
	Mar. 31, 2019
Premiums Written, Net [Abstract]
Property Casualty Loss And Loss Expenses	Property Casualty Loss and Loss Expenses This table summarizes activity for our consolidated property casualty loss and loss expense reserves: (Dollars in millions) Three months ended March 31, 2019 2018 Gross loss and loss expense reserves, beginning of period $ 5,646 $ 5,219 Less reinsurance recoverable 238 187 Net loss and loss expense reserves, beginning of period 5,408 5,032 Net loss and loss expense reserves related to acquisition of MSP at February 28, 2019 246 — Net incurred loss and loss expenses related to: Current accident year 857 839 Prior accident years (67 ) (48 ) Total incurred 790 791 Net paid loss and loss expenses related to: Current accident year 177 195 Prior accident years 647 519 Total paid 824 714 Net loss and loss expense reserves, end of period 5,620 5,109 Plus reinsurance recoverable 266 184 Gross loss and loss expense reserves, end of period $ 5,886 $ 5,293 We use actuarial methods, models and judgment to estimate, as of a financial statement date, the property casualty loss and loss expense reserves required to pay for and settle all outstanding insured claims, including incurred but not reported (IBNR) claims, as of that date. The actuarial estimate is subject to review and adjustment by an inter-departmental committee that includes actuarial, claims, underwriting, loss prevention and accounting management. This committee is familiar with relevant company and industry business, claims and underwriting trends, as well as general economic and legal trends that could affect future loss and loss expense payments. The amount we will actually have to pay for claims can be highly uncertain. This uncertainty, together with the size of our reserves, makes the loss and loss expense reserves our most significant estimate. The reserve for loss and loss expenses in the condensed consolidated balance sheets also included $58 million at March 31, 2019 , and $52 million at March 31, 2018 , for certain life and health loss and loss expense reserves. For the three months ended March 31, 2019 , we experienced $67 million of favorable development on prior accident years, including $62 million of favorable development in commercial lines, $3 million of unfavorable development in personal lines and $2 million of favorable development in excess and surplus lines. Within commercial lines, we recognized favorable reserve development of $31 million for the commercial casualty line, $15 million for the workers' compensation line and $11 million for the commercial auto line due to reduced uncertainty of prior accident year loss and loss adjustment expense for these lines. Within personal lines, we recognized unfavorable reserve development of $11 million for the homeowner line of business due primarily to higher-than-anticipated loss development on known claims. For the three months ended March 31, 2018 , we experienced $48 million of favorable development on prior accident years, including $35 million of favorable development in commercial lines, $1 million of favorable development in personal lines, $10 million of favorable development in excess and surplus lines and $2 million of favorable development in our reinsurance assumed operations. This included $7 million from favorable development of catastrophe losses. Within commercial lines, we recognized favorable reserve development of $21 million for the commercial property line, $13 million for the workers' compensation line, $2 million for the commercial auto line and $4 million for the other commercial lines due to reduced uncertainty of prior accident year loss and loss adjustment expenses for these lines. We recognized unfavorable reserve development of $5 million for the commercial casualty line. The unfavorable reserve development for commercial casualty was primarily due to an increase in case reserves for accident year 2017.

Life Policy and Investment Cont

Life Policy and Investment Contract Reserves	3 Months Ended
	Mar. 31, 2019
Liability for Future Policy Benefits [Abstract]
Life Policy And Investment Contract Reserves	Life Policy and Investment Contract Reserves We establish the reserves for traditional life insurance policies based on expected expenses, mortality, morbidity, withdrawal rates, timing of claim presentation and investment yields, including a provision for uncertainty. Once these assumptions are established, they generally are maintained throughout the lives of the contracts. We use both our own experience and industry experience, adjusted for historical trends, in arriving at our assumptions for expected mortality, morbidity and withdrawal rates as well as for expected expenses. We base our assumptions for expected investment income on our own experience adjusted for current economic conditions. We establish reserves for the company’s deferred annuity, universal life and structured settlement policies equal to the cumulative account balances, which include premium deposits plus credited interest less charges and withdrawals. Some of our universal life policies contain no-lapse guarantee provisions. For these policies, we establish a reserve in addition to the account balance, based on expected no-lapse guarantee benefits and expected policy assessments. This table summarizes our life policy and investment contract reserves: (Dollars in millions) March 31, December 31, 2018 Life policy reserves: Ordinary/traditional life $ 1,168 $ 1,149 Other 48 48 Subtotal 1,216 1,197 Investment contract reserves: Deferred annuities 776 787 Universal life 632 632 Structured settlements 154 156 Other 6 7 Subtotal 1,568 1,582 Total life policy and investment contract reserves $ 2,784 $ 2,779

Deferred Acquisition Costs

Deferred Acquisition Costs	3 Months Ended
	Mar. 31, 2019
Deferred Costs [Abstract]
Deferred Acquisition Costs	Deferred Policy Acquisition Costs Expenses directly related to successfully acquired insurance policies – primarily commissions, premium taxes and underwriting costs – are deferred and amortized over the terms of the policies. We update our acquisition cost assumptions periodically to reflect actual experience, and we evaluate the costs for recoverability. The table below shows the deferred policy acquisition costs and asset reconciliation. (Dollars in millions) Three months ended March 31, 2019 2018 Property casualty: Deferred policy acquisition costs asset, beginning of period $ 464 $ 438 Capitalized deferred policy acquisition costs 254 232 Amortized deferred policy acquisition costs (233 ) (224 ) Deferred policy acquisition costs asset, end of period $ 485 $ 446 Life: Deferred policy acquisition costs asset, beginning of period $ 274 $ 232 Capitalized deferred policy acquisition costs 16 13 Amortized deferred policy acquisition costs (13 ) (10 ) Shadow deferred policy acquisition costs (11 ) 10 Deferred policy acquisition costs asset, end of period $ 266 $ 245 Consolidated: Deferred policy acquisition costs asset, beginning of period $ 738 $ 670 Capitalized deferred policy acquisition costs 270 245 Amortized deferred policy acquisition costs (246 ) (234 ) Shadow deferred policy acquisition costs (11 ) 10 Deferred policy acquisition costs asset, end of period $ 751 $ 691 No premium deficiencies were recorded in the condensed consolidated statements of income, as the sum of the anticipated loss and loss expenses, policyholder dividends and unamortized deferred acquisition expenses did not exceed the related unearned premiums and anticipated investment income.

Accumulated Other Comprehensive

Accumulated Other Comprehensive Income	3 Months Ended
	Mar. 31, 2019
Accumulated Other Comprehensive Income [Abstract]
Accumulated Other Comprehensive Income	Accumulated Other Comprehensive Income Accumulated other comprehensive income (AOCI) includes changes in unrealized gains and losses on investments, changes in pension obligations and changes in life deferred acquisition costs, life policy reserves and other as follows: (Dollars in millions) Three months ended March 31, 2019 2018 Before tax Income tax Net Before tax Income tax Net Investments: AOCI, beginning of period $ 46 $ 9 $ 37 $ 3,540 $ 733 $ 2,807 Cumulative effect of change in accounting for equity securities as of January 1, 2018 — — — (3,155 ) (652 ) (2,503 ) Adjusted AOCI, beginning of period 46 9 37 385 81 304 OCI before investment gains and losses, net, recognized in net income 244 51 193 (217 ) (45 ) (172 ) Investment gains and losses, net, recognized in net income (2 ) (1 ) (1 ) (4 ) (1 ) (3 ) OCI 242 50 192 (221 ) (46 ) (175 ) AOCI, end of period $ 288 $ 59 $ 229 $ 164 $ 35 $ 129 Pension obligations: AOCI, beginning of period $ (16 ) $ (2 ) $ (14 ) $ (12 ) $ (1 ) $ (11 ) OCI excluding amortization recognized in net income — — — — — — Amortization recognized in net income — — — — — — OCI — — — — — — AOCI, end of period $ (16 ) $ (2 ) $ (14 ) $ (12 ) $ (1 ) $ (11 ) Life deferred acquisition costs, life policy reserves and other: AOCI, beginning of period $ (1 ) $ — $ (1 ) $ (10 ) $ (2 ) $ (8 ) OCI before investment gains and losses, net, recognized in net income — — — 6 1 5 Investment gains and losses, net, recognized in net income (5 ) (1 ) (4 ) — — — OCI (5 ) (1 ) (4 ) 6 1 5 AOCI, end of period $ (6 ) $ (1 ) $ (5 ) $ (4 ) $ (1 ) $ (3 ) Summary of AOCI: AOCI, beginning of period $ 29 $ 7 $ 22 $ 3,518 $ 730 $ 2,788 Cumulative effect of change in accounting for equity securities as of January 1, 2018 — — — (3,155 ) (652 ) (2,503 ) Adjusted AOCI, beginning of period 29 7 22 363 78 285 Investments OCI 242 50 192 (221 ) (46 ) (175 ) Pension obligations OCI — — — — — — Life deferred acquisition costs, life policy reserves and other OCI (5 ) (1 ) (4 ) 6 1 5 Total OCI 237 49 188 (215 ) (45 ) (170 ) AOCI, end of period $ 266 $ 56 $ 210 $ 148 $ 33 $ 115 Investment gains and losses, net, and life deferred acquisition costs, life policy reserves and other investment gains and losses, net, are recorded in the investment gains and losses, net, line item in the condensed consolidated statements of income. Amortization on pension obligations is recorded in the insurance losses and contract holders' benefits and underwriting, acquisition and insurance expenses in the condensed consolidated statements of income.

Reinsurance

Reinsurance	3 Months Ended
	Mar. 31, 2019
Reinsurance Disclosures [Abstract]
Reinsurance	Reinsurance Primary components of our property casualty reinsurance assumed operations include involuntary and voluntary assumed risks as well as contracts from our reinsurance assumed operations, known as Cincinnati Re. Primary components of our ceded reinsurance include a property per risk treaty, property excess treaty, casualty per occurrence treaty, casualty excess treaty, property catastrophe treaty and catastrophe bonds and retrocessions on our reinsurance assumed operations. Management's decisions about the appropriate level of risk retention are affected by various factors, including changes in our underwriting practices, capacity to retain risks and reinsurance market conditions. The table below summarizes our consolidated property casualty insurance net written premiums, earned premiums and incurred loss and loss expenses: (Dollars in millions) Three months ended March 31, 2019 2018 Direct written premiums $ 1,335 $ 1,247 Assumed written premiums 87 49 Ceded written premiums (41 ) (38 ) Net written premiums $ 1,381 $ 1,258 Direct earned premiums $ 1,266 $ 1,207 Assumed earned premiums 43 33 Ceded earned premiums (42 ) (40 ) Earned premiums $ 1,267 $ 1,200 Direct incurred loss and loss expenses $ 787 $ 781 Assumed incurred loss and loss expenses 25 16 Ceded incurred loss and loss expenses (22 ) (6 ) Incurred loss and loss expenses $ 790 $ 791 Our life insurance company purchases reinsurance for protection of a portion of the risks that are written. Primary components of our life reinsurance program include individual mortality coverage, aggregate catastrophe and accidental death coverage in excess of certain deductibles. The table below summarizes our consolidated life insurance earned premiums and contract holders' benefits incurred: (Dollars in millions) Three months ended March 31, 2019 2018 Direct earned premiums $ 83 $ 77 Ceded earned premiums (17 ) (17 ) Earned premiums $ 66 $ 60 Direct contract holders' benefits incurred 85 76 Ceded contract holders' benefits incurred (15 ) (13 ) Contract holders' benefits incurred $ 70 $ 63 The ceded benefits incurred can vary depending on the type of life insurance policy held and the year the policy was issued.

Income Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2019
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The differences between the 21 % statutory federal income tax rate and our effective income tax rate were as follows: (Dollars in millions) Three months ended March 31, 2019 2018 Tax at statutory rate: $ 182 21.0 % $ (11 ) 21.0 % Increase (decrease) resulting from: Tax-exempt income from municipal bonds (5 ) (0.6 ) (5 ) 10.0 Dividend received exclusion (4 ) (0.5 ) (3 ) 6.0 Other (1 ) (0.1 ) — 1.0 Provision for income taxes $ 172 19.8 % $ (19 ) 38.0 % The provision for federal income taxes is based upon filing a consolidated income tax return for the company and its subsidiaries. Unrecognized Tax Benefits As of March 31, 2019, and December 31, 2018, we had a gross unrecognized tax benefit of $34 million . There were no changes to this amount during the first quarter of 2019. Acquisition of MSP As more fully discussed in Note 1, Accounting Policies and Note 14, Acquisition, we closed on the acquisition of MSP during the first quarter of 2019. As a result of this acquisition, $59 million of net deferred tax assets were acquired or established at the acquisition date with an offsetting valuation allowance of $55 million . Accounting guidance requires deferred tax assets to be reduced by a valuation allowance when management believes it is more likely than not that some, or all, of the deferred tax assets will not be realized. After considering all positive and negative evidence related to the MSP operations, we believe it was appropriate to set up a valuation allowance for purposes of our opening MSP balance sheet. The purchase price allocation to our MSP deferred tax assets and corresponding valuation allowance is subject to further post-closing adjustments based on the actual net asset value (NAV) of MSP and its subsidiaries at closing, pursuant to the procedures set forth in the sale and purchase agreement. As a result of first quarter operations, there were immaterial changes to the MSP valuation allowance as of March 31, 2019. As of March 31, 2019, MSP had operating loss carryforwards of $192 million which are subject to certain limitations. These MSP losses can only be utilized within the MSP group and cannot offset the income of our CFC group. Other than the MSP loss carryforwards, we had no other operating or capital loss carryforwards as of March 31, 2019.

Net Income Per Common Share

Net Income Per Common Share	3 Months Ended
	Mar. 31, 2019
Earnings Per Share [Abstract]
Net Income Per Common Share	Basic earnings per share are computed based on the weighted average number of common shares outstanding. Diluted earnings per share are computed based on the weighted average number of common and dilutive potential common shares outstanding using the treasury stock method. The table shows calculations for basic and diluted earnings per share: (In millions, except per share data) Three months ended March 31, 2019 2018 Numerator: Net income (loss)—basic and diluted $ 695 $ (31 ) Denominator: Basic weighted-average common shares outstanding 163.0 164.0 Effect of share-based awards: Stock options 0.9 — Nonvested shares 0.7 — Diluted weighted-average shares 164.6 164.0 Earnings per share: Basic $ 4.27 $ (0.19 ) Diluted $ 4.22 $ (0.19 ) Number of anti-dilutive share-based awards 0.7 2.8 The sources of dilution of our common shares are certain equity-based awards. See our 2018 Annual Report on Form 10-K, Item 8, Note 17, Share-Based Associate Compensation Plans, Page 173, for information about share-based awards. The above table shows the number of anti-dilutive share-based awards for the three months ended March 31, 2019 and 2018 . These share-based awards were not included in the computation of net income (loss) per common share (diluted) because their exercise would have anti-dilutive effects. In accordance with ASC 260, Earnings per Share , the assumed exercise of share-based awards in 2018 were excluded from the computation of diluted loss per share.

Employee Retirement Benefits

Employee Retirement Benefits	3 Months Ended
	Mar. 31, 2019
Retirement Benefits [Abstract]
Employee Retirement Benefits	Employee Retirement Benefits The following summarizes the components of net periodic benefit cost for our qualified and supplemental pension plans: (Dollars in millions) Three months ended March 31, 2019 2018 Service cost $ 2 $ 3 Non-service costs (benefit): Interest cost 3 3 Expected return on plan assets (5 ) (5 ) Amortization of actuarial loss and prior service cost — — Other 1 — Total non-service benefit (1 ) (2 ) Net periodic benefit cost $ 1 $ 1 See our 2018 Annual Report on Form 10-K, Item 8, Note 13, Employee Retirement Benefits, Page 166, for information on our retirement benefits. Service costs and non-service costs (benefit) are allocated in the same proportion primarily to the underwriting, acquisition and insurance expenses line item with the remainder allocated to the insurance losses and contract holders' benefits line item on the condensed consolidated statements of income for both 2019 and 2018. We made matching contributions totaling $5 million and $6 million to our 401(k) and Top Hat savings plans during the first quarter s of 2019 and 2018. We made no contributions to our qualified pension plan during the first three months of 2019.

Commitments and Contingent Liab

Commitments and Contingent Liabilities	3 Months Ended
	Mar. 31, 2019
Commitments and Contingencies Disclosure [Abstract]
Commitments And Contingent Liabilities	Commitments and Contingent Liabilities In the ordinary course of conducting business, the company and its subsidiaries are named as defendants in various legal proceedings. Most of these proceedings are claims litigation involving the company's insurance subsidiaries in which the company is either defending or providing indemnity for third-party claims brought against insureds or litigating first-party coverage claims. The company accounts for such activity through the establishment of unpaid loss and loss expense reserves. We believe that the ultimate liability, if any, with respect to such ordinary-course claims litigation, after consideration of provisions made for potential losses and costs of defense, is immaterial to our consolidated financial condition, results of operations and cash flows. The company and its subsidiaries also are occasionally involved in other legal and regulatory proceedings, some of which assert claims for substantial amounts. These actions include, among others, putative class actions seeking certification of a state or national class. Such proceedings have alleged, for example, breach of an alleged duty to search national databases to ascertain unreported deaths of insureds under life insurance policies. The company's insurance subsidiaries also are occasionally parties to individual actions in which extra-contractual damages, punitive damages or penalties are sought, such as claims alleging bad faith handling of insurance claims or writing unauthorized coverage or claims alleging discrimination by former or current associates. On a quarterly basis, we review these outstanding matters. Under current accounting guidance, we establish accruals when it is probable that a loss has been incurred and we can reasonably estimate its potential exposure. The company accounts for such probable and estimable losses, if any, through the establishment of legal expense reserves. Based on our quarterly review, we believe that our accruals for probable and estimable losses are reasonable and that the amounts accrued do not have a material effect on our consolidated financial condition or results of operations. However, if any one or more of these matters results in a judgment against us or settlement for an amount that is significantly greater than the amount accrued, the resulting liability could have a material effect on the company's consolidated results of operations or cash flows. Based on our most recent review, our estimate for any other matters for which the risk of loss is not probable, but more than remote, is immaterial.

Segment Information

Segment Information	3 Months Ended
	Mar. 31, 2019
Segment Reporting [Abstract]
Segment Information	Segment Information We operate primarily in two industries, property casualty insurance and life insurance. Our chief operating decision maker regularly reviews our reporting segments to make decisions about allocating resources and assessing performance. Our reporting segments are: • Commercial lines insurance • Personal lines insurance • Excess and surplus lines insurance • Life insurance • Investments We report as Other the noninvestment operations of the parent company and its noninsurer subsidiary, CFC Investment Company. We also report as Other the underwriting results of Cincinnati Re, our reinsurance assumed operation, and MSP, our London-based global specialty underwriter, which was acquired on February 28, 2019. See our 2018 Annual Report on Form 10-K, Item 8, Note 18, Segment Information, Page 176, for a description of revenue, income or loss before income taxes and identifiable assets for each of the five segments. Segment information is summarized in the following table: (Dollars in millions) Three months ended March 31, 2019 2018 Revenues: Commercial lines insurance Commercial casualty $ 268 $ 265 Commercial property 234 228 Commercial auto 170 161 Workers' compensation 77 80 Other commercial 61 56 Commercial lines insurance premiums 810 790 Fee revenues 1 2 Total commercial lines insurance 811 792 Personal lines insurance Personal auto 155 151 Homeowner 147 136 Other personal 42 38 Personal lines insurance premiums 344 325 Fee revenues 1 1 Total personal lines insurance 345 326 Excess and surplus lines insurance 63 56 Fee revenues 1 — Total excess and surplus lines insurance 64 56 Life insurance premiums 66 60 Fee revenues 1 1 Total life insurance 67 61 Investments Investment income, net of expenses 157 150 Investment gains and losses, net 663 (191 ) Total investment revenue 820 (41 ) Other Earned premiums 50 29 Other 2 1 Total other revenues 52 30 Total revenues $ 2,159 $ 1,224 Income (loss) before income taxes: Insurance underwriting results Commercial lines insurance $ 76 $ 15 Personal lines insurance (4 ) (9 ) Excess and surplus lines insurance 11 18 Life insurance (1 ) 2 Investments 796 (65 ) Other (11 ) (11 ) $ 867 $ (50 ) Identifiable assets: March 31, December 31, 2018 Property casualty insurance $ 3,308 $ 3,285 Life insurance 1,472 1,424 Investments 17,738 16,741 Other 834 485 Total $ 23,352 $ 21,935

Acquisition

Acquisition	3 Months Ended
	Mar. 31, 2019
Business Combinations [Abstract]
Acquisition	On February 28, 2019 (closing date or acquisition date), pursuant to the agreement (the SPA) for the sale and purchase of the entire issued share capital of MSP Underwriting Limited, dated October 11, 2018, by and between the company and Münchener Rückversicherungs Gesellschaft AG (Munich Re), the company acquired from Munich Re all of the issued and outstanding share capital of MSP and its subsidiaries, including the Lloyd’s managing agent, Beaufort Underwriting Agency Limited for Syndicate 318 (the acquisition). MSP, which operates through Beaufort Underwriting Agency Limited, is a London based global specialty underwriter. The acquisition of MSP reflects progress toward our long-term objective of diversifying revenue and profitability by expanding our operations geographically and by line of business. As aggregate consideration for the purchase of the share capital of MSP and its subsidiaries, the company paid £ 48 million , or $64 million , in cash to Munich Re at the closing of the acquisition. The amount paid at closing consisted of an originally estimated £102 million decreased by a NAV adjustment, calculated as the difference between the target NAV set forth in the SPA and the estimated NAV of MSP and its subsidiaries at the closing date. The purchase price is subject to further post-closing adjustments based on the actual NAV of MSP and its subsidiaries at closing, pursuant to the procedures set forth in the SPA. The allocation of the purchase price is based on information included in MSP's financial statements at the closing date, which is subject to negotiation per the SPA. The purchase price allocation is subject to change if additional information becomes available within the measurement period, which cannot exceed 12 months from the acquisition date. The fair values of the assets acquired and liabilities assumed may be subject to adjustments, which may impact the amounts recorded for the assets acquired and liabilities assumed as well as the goodwill. The fair value of the assets acquired, liabilities assumed and the allocation of the purchase price on the acquisition date have been summarized in the following table: (Dollars in millions) Amount Assets Investments and other invested assets $ 198 Cash and cash equivalents 64 Premiums receivable 45 Reinsurance recoverable 42 Other assets 23 Total assets acquired $ 372 Liabilities Loss and loss expense reserves $ 277 Unearned premiums 88 Other liabilities 24 Total liabilities assumed $ 389 Fair value of identifiable intangible assets: Syndicate capacity - indefinite lived $ 31 Syndicate broker relationships - definite lived 12 Value of business acquired - definite lived 4 Internally developed technology - definite lived 3 Total fair value of identifiable intangible assets $ 50 Total purchase price paid $ 64 Total assets acquired (including fair value of identifiable intangible assets) 422 Total liabilities assumed 389 Fair value of net assets acquired prior to allocation of goodwill 33 Excess of purchase price paid over fair value of net assets acquired assigned to goodwill $ 31 Identifiable intangible assets and goodwill are included in other assets in the condensed consolidated balance sheets. The goodwill arose as the fair value of the consideration transferred exceeded the fair value of the net identifiable assets acquired at the acquisition date. The broker relationships and internally developed technology will be amortized straight-line over five and 15 years , respectively. Value of business acquired will be amortized over the remaining coverage period of the underlying insurance contracts. Goodwill and intangibles are tested for impairment on an annual basis or more frequently if events or circumstances indicate the assets might be impaired. The company will perform its annual impairment test on goodwill and intangibles on September 30 of each year. The financial results of MSP are included in the condensed consolidated statements of income from the acquisition date and are deemed to be immaterial. In connection with the acquisition, the company incurred immaterial transaction related expenses.

Accounting Policies Pending Acc

Accounting Policies Pending Accounting Updates (Policies)	3 Months Ended
	Mar. 31, 2019
Accounting Policies [Abstract]
Adopted Accounting Updates and Pending Accounting Updates	Adopted Accounting Updates ASU 2016-02, Leases (Topic 842) In February 2016, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) 2016-02, Leases (Topic 842). The main provision of ASU 2016-02 requires the recognition of lease assets and lease liabilities by lessees for those leases classified as operating leases under previous GAAP. The effective date of ASU 2016-02 is for interim and annual reporting periods beginning after December 15, 2018. In July 2018, the FASB issued ASU 2018-10, Codification Improvements to Topic 842 and ASU 2018-11, Targeted Improvements to Topic 842 . ASU 2018-10 makes narrow-scope amendments to certain aspects of the new leasing standard while ASU 2018-11 provides relief from costs of implementing certain aspects of the new leasing standard. The company adopted this ASU effective January 1, 2019, and it did not have a material impact on our company’s consolidated financial position, cash flows or results of operations. The company has elected the practical expedient package for carrying forward historical lease classifications, not re-evaluating for embedded leases and not reassessing initial direct costs. The company also elected additional practical expedients to not recognize short-term leases on the balance sheet and to only combine lease and nonlease components for certain asset classes. We also elected not to restate prior periods. In support of its insurance operations, the company leases real estate properties which qualify as operating leases and also leases equipment and autos which qualify as finance leases. The lease term for real estate properties is typically five years while the term for equipment and autos is three to six years. ASU 2017-08, Receivables - Nonrefundable Fees and Other Costs (Subtopic 310-20): Premium Amortization on Purchased Callable Debt Securities In March 2017, the FASB issued ASU 2017-08, Receivables - Nonrefundable Fees and Other Costs (Subtopic 310-20): Premium Amortization on Purchased Callable Debt Securities. ASU 2017-08 amends guidance on the amortization period of premiums on certain purchased callable debt securities. The amendments shorten the amortization period of premiums on certain purchased callable debt securities to the earliest call date. The amendments should be applied on a modified retrospective basis through a cumulative-effect adjustment to beginning retained earnings. The effective date of ASU 2017-08 is for interim and annual reporting periods beginning after December 15, 2018. The company adopted this ASU effective January 1, 2019, and it did not have a material impact on our company's consolidated financial position, cash flows or results of operations. ASU 2018-07, Compensation - Stock Compensation (Topic 718) - Improvements to Nonemployee Share-Based Payment Accounting In June 2018, the FASB issued ASU 2018-07, Compensation - Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting . ASU 2018-07 expands the scope of Topic 718, Compensation - Stock Compensation, which currently only includes share-based payments issued to employees, to include share-based payments issued to nonemployees for the acquisition of goods and services. The effective date of ASU 2018-07 is for interim and annual reporting periods beginning after December 15, 2018. The company adopted this ASU effective January 1, 2019, and it did not have a material impact on our company's consolidated financial position, cash flows or results of operations. Pending Accounting Updates ASU 2016-13, Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments In June 2016, the FASB issued ASU 2016-13, Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments . ASU 2016-13 amends previous guidance on the impairment of financial instruments by adding an impairment model that allows an entity to recognize expected credit losses as an allowance rather than impairing as they are incurred. The new guidance is intended to reduce complexity of credit impairment models and result in a more timely recognition of expected credit losses. The effective date of ASU 2016-13 is for interim and annual reporting periods beginning after December 15, 2019. The ASU has not yet been adopted. Management is currently evaluating the impact on our company's consolidated financial position, cash flows and results of operations. ASU 2017-04, Intangibles - Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment In January 2017, the FASB issued ASU 2017-04, Intangibles - Goodwill and Other (Topic 350) - Simplifying the Test for Goodwill Impairment . ASU 2017-04 simplifies the subsequent measurement of goodwill by eliminating Step 2 from the goodwill impairment test. Instead, an entity should perform its goodwill impairment test by comparing the fair value of a reporting unit with its carrying amount and recognize an impairment charge for the amount by which the carrying amount exceeds the reporting unit's fair value. The loss recognized should not exceed the total amount of goodwill allocated to that reporting unit and income tax effects from any tax deductible goodwill on the carrying amount of the reporting unit should be considered. The effective date of ASU 2017-04 is for interim and annual goodwill impairment tests performed in any fiscal years beginning after December 15, 2019. The ASU has not yet been adopted; however, it is not expected to have a material impact on our company's consolidated financial position, cash flows or results of operations. ASU 2018-12, Financial Services - Insurance (Topic 944): Targeted Improvements to the Accounting for Long-Duration Contracts In August 2018, the FASB issued ASU 2018-12, Financial Services - Insurance (Topic 944): Targeted Improvements to the Accounting for Long-Duration Contracts . ASU 2018-12 is intended to improve the timeliness of recognizing changes in the liability for future policy benefits and modify the rate used to discount future cash flows. The ASU will simplify and improve the accounting for certain market-based options or guarantees associated with deposit or account balance contracts, simplify amortization of deferred acquisition costs while improving and expanding required disclosures. The effective date of ASU 2018-12 is for interim and annual reporting periods beginning after December 15, 2020. The ASU has not yet been adopted. Management is currently evaluating the impact on our company's consolidated financial position, cash flows and results of operations. ASU 2018-13, Fair Value Measurement (Topic 820): Disclosure Framework - Changes to the Disclosure Requirements for Fair Value Measurement In August 2018, the FASB issued ASU 2018-13, Fair Value Measurement (Topic 820): Disclosure Framework - Changes to the Disclosure Requirements for Fair Value Measurement . ASU 2018-13 clarifies the fair value measurement disclosure requirements of ASC 820 by adding, eliminating and modifying disclosures. The effective date of ASU 2018-13 is for interim and annual reporting periods beginning after December 15, 2019. The ASU has not yet been adopted; however, it is not expected to have a material impact on our company's consolidated financial position, cash flows or results of operations. ASU 2018-14, Compensation - Retirement Benefits - Defined Benefit Plans - General (Topic 715-20): Disclosure Framework - Changes to the Disclosure Requirements for Defined Benefit Plans In August 2018, the FASB issued ASU 2018-14, Compensation - Retirement Benefits - Defined Benefit Plans - General (Topic 715-20): Disclosure Framework - Changes to the Disclosure Requirements for Defined Benefit Plans . ASU 2018-14 clarifies the guidance in ASC 715 to add, remove, and clarify disclosure requirements related to defined benefit pension and other postretirement plans. The effective date of ASU 2018-14 is for annual reporting periods ending after December 15, 2020. The ASU has not yet been adopted; however, it is not expected to have a material impact on our company's consolidated financial position, cash flows or results of operations. ASU 2018-15, Customer's Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract In August 2018, the FASB issued ASU 2018-15, Customer's Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract . ASU 2018-15 amends ASC 350 to include implementation costs of a cloud computing arrangement that is a service contract and clarifies that a customer should apply ASC 350-40 to determine which implementation costs should be capitalized in a cloud computing arrangement that is considered a service contract. The effective date of ASU 2018-15 is for interim and annual reporting periods beginning after December 15, 2019. The ASU has not yet been adopted. Management is currently evaluating the impact on our company's consolidated financial position, cash flows and results of operations.

Investments (Tables)

Investments (Tables)	3 Months Ended
	Mar. 31, 2019
Investments [Abstract]
Analysis Of Cost Or Amortized Cost, Gross Unrealized Gains And Losses And Fair Value for Investments	The following table provides cost or amortized cost, gross unrealized gains, gross unrealized losses and fair value for our fixed-maturity securities: (Dollars in millions) Cost or amortized cost Gross unrealized Fair value At March 31, 2019 gains losses Fixed maturity securities: Corporate $ 5,753 $ 160 $ 25 $ 5,888 States, municipalities and political subdivisions 4,269 153 3 4,419 Government-sponsored enterprises 305 — 3 302 Commercial mortgage-backed 292 6 1 297 United States government 99 1 — 100 Foreign government 16 — — 16 Total $ 10,734 $ 320 $ 32 $ 11,022 At December 31, 2018 Fixed maturity securities: Corporate $ 5,712 $ 85 $ 87 $ 5,710 States, municipalities and political subdivisions 4,251 84 31 4,304 Government-sponsored enterprises 316 1 7 310 Commercial mortgage-backed 287 3 2 288 United States government 67 1 1 67 Foreign government 10 — — 10 Total $ 10,643 $ 174 $ 128 $ 10,689
Fair Values And Unrealized Losses by Investment Category And By The Duration Of The Securities' Continuous Unrealized Loss Position	The table below provides fair values and gross unrealized losses by investment category and by the duration of the securities’ continuous unrealized loss positions: (Dollars in millions) Less than 12 months 12 months or more Total At March 31, 2019 Fair value Unrealized losses Fair value Unrealized losses Fair value Unrealized losses Fixed maturity securities: Corporate $ 343 $ 5 $ 685 $ 20 $ 1,028 $ 25 States, municipalities and political subdivisions 10 — 237 3 247 3 Government-sponsored enterprises 7 — 204 3 211 3 Commercial mortgage-backed securities 2 — 45 1 47 1 United States government — — 23 — 23 — Total $ 362 $ 5 $ 1,194 $ 27 $ 1,556 $ 32 At December 31, 2018 Fixed maturity securities: Corporate $ 2,082 $ 51 $ 501 $ 36 $ 2,583 $ 87 States, municipalities and political subdivisions 823 18 340 13 1,163 31 Government-sponsored enterprises 49 1 211 6 260 7 Commercial mortgage-backed 77 — 64 2 141 2 United States government — — 33 1 33 1 Total $ 3,031 $ 70 $ 1,149 $ 58 $ 4,180 $ 128
Investments Classified by Contractual Maturity Date [Table Text Block]	Contractual maturity dates for fixed-maturities investments were: (Dollars in millions) Amortized cost Fair value % of fair value At March 31, 2019 Maturity dates: Due in one year or less $ 598 $ 604 5.5 % Due after one year through five years 2,977 3,039 27.6 Due after five years through ten years 3,656 3,742 33.9 Due after ten years 3,503 3,637 33.0 Total $ 10,734 $ 11,022 100.0 %
Investment Income, Realized Investment Gains And Losses And Change In Unrealized Investment Gains And Losses	The following table provides investment income and investment gains and losses, net: (Dollars in millions) Three months ended March 31, 2019 2018 Investment income: Interest $ 111 $ 110 Dividends 46 42 Other 3 1 Total 160 153 Less investment expenses 3 3 Total $ 157 $ 150 Investment gains and losses, net: Equity securities: Investment gains and losses on securities sold, net $ 4 $ 3 Unrealized gains and losses on securities still held, net 652 (198 ) Subtotal 656 (195 ) Fixed maturities: Gross realized gains 2 4 Subtotal 2 4 Other 5 — Total $ 663 $ (191 )

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	3 Months Ended
	Mar. 31, 2019
Fair Value Disclosures [Abstract]
Fair Value Hierarchy for Assets Measured at Fair Value on a Recurring Basis	The following tables illustrate the fair value hierarchy for those assets measured at fair value on a recurring basis at March 31, 2019 , and December 31, 2018 . We do not have any liabilities carried at fair value. There were no transfers between Level 1 and Level 2. (Dollars in millions) Quoted prices in active markets for identical assets (Level 1) Significant other observable inputs (Level 2) Significant unobservable inputs (Level 3) Total At March 31, 2019 Fixed maturities, available for sale: Corporate $ — $ 5,887 $ 1 $ 5,888 States, municipalities and political subdivisions — 4,415 4 4,419 Government-sponsored enterprises — 302 — 302 Commercial mortgage-backed — 297 — 297 United States government 100 — — 100 Foreign government — 16 — 16 Subtotal 100 10,917 5 11,022 Common equities 6,381 — — 6,381 Nonredeemable preferred equities — 190 — 190 Separate accounts taxable fixed maturities — 820 — 820 Top Hat savings plan mutual funds and common 38 — — 38 Total $ 6,519 $ 11,927 $ 5 $ 18,451 At December 31, 2018 Fixed maturities, available for sale: Corporate $ — $ 5,709 $ 1 $ 5,710 States, municipalities and political subdivisions — 4,300 4 4,304 Government-sponsored enterprises — 310 — 310 Commercial mortgage-backed — 288 — 288 United States government 67 — — 67 Foreign government — 10 — 10 Subtotal 67 10,617 5 10,689 Common equities 5,742 — — 5,742 Nonredeemable preferred equities — 178 — 178 Separate accounts taxable fixed maturities — 791 — 791 Top Hat savings plan mutual funds and common equity (included in Other assets) 34 — — 34 Total $ 5,843 $ 11,586 $ 5 $ 17,434
Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3)	The following table provides the change in Level 3 assets for the three months ended March 31 : (Dollars in millions) Asset fair value measurements using significant unobservable inputs Corporate fixed maturities States, Total Beginning balance, January 1, 2019 $ 1 $ 4 $ 5 Total gains or losses (realized/unrealized): Included in net income — — — Included in other comprehensive income — — — Purchases — — — Sales — — — Transfers into Level 3 — — — Transfers out of Level 3 — — — Ending balance, March 31, 2019 $ 1 $ 4 $ 5 Beginning balance, January 1, 2018 $ 1 $ 5 $ 6 Total gains or losses (realized/unrealized): Included in net income (loss) — — — Included in other comprehensive income (loss) — (1 ) (1 ) Purchases — — — Sales — — — Transfers into Level 3 — — — Transfers out of Level 3 — — — Ending balance, March 31, 2018 $ 1 $ 4 $ 5
Schedule of Carrying Values and Estimated Fair Values of Debt Instruments [Table Text Block]	This table summarizes the book value and principal amounts of our long-term debt: (Dollars in millions) Book value Principal amount Interest rate Year of issue March 31, December 31, March 31, December 31, 2019 2018 2019 2018 6.900 % 1998 Senior debentures, due 2028 $ 27 $ 27 $ 28 $ 28 6.920 % 2005 Senior debentures, due 2028 391 391 391 391 6.125 % 2004 Senior notes, due 2034 370 370 374 374 Total $ 788 $ 788 $ 793 $ 793
Fair Values of Deferred Annuities, Structured Settlements and Other Items	The following table shows fair values of our note payable and long-term debt: (Dollars in millions) Quoted prices in active markets for identical assets (Level 1) Significant other observable inputs (Level 2) Significant unobservable inputs (Level 3) Total At March 31, 2019 Note payable $ — $ 32 $ — $ 32 6.900% senior debentures, due 2028 — 33 — 33 6.920% senior debentures, due 2028 — 486 — 486 6.125% senior notes, due 2034 — 459 — 459 Total $ — $ 1,010 $ — $ 1,010 At December 31, 2018 Note payable $ — $ 32 $ — $ 32 6.900% senior debentures, due 2028 — 32 — 32 6.920% senior debentures, due 2028 — 471 — 471 6.125% senior notes, due 2034 — 440 — 440 Total $ — $ 975 $ — $ 975
Fair Value of Life Policy Loans	The following table shows the fair value of our life policy loans included in other invested assets and the fair values of our deferred annuities and structured settlements included in life policy and investment contract reserves: (Dollars in millions) Quoted prices in active markets for identical assets (Level 1) Significant other observable inputs (Level 2) Significant unobservable inputs (Level 3) Total At March 31, 2019 Life policy loans $ — $ — $ 41 $ 41 Deferred annuities — — 751 751 Structured settlements — 195 — 195 Total $ — $ 195 $ 751 $ 946 At December 31, 2018 Life policy loans $ — $ — $ 40 $ 40 Deferred annuities — — 742 742 Structured settlements — 185 — 185 Total $ — $ 185 $ 742 $ 927

Property Casualty Loss and Lo_2

Property Casualty Loss and Loss Expenses (Tables)	3 Months Ended
	Mar. 31, 2019
Premiums Written, Net [Abstract]
Consolidated Property Casualty Loss And Loss Expense Reserves	This table summarizes activity for our consolidated property casualty loss and loss expense reserves: (Dollars in millions) Three months ended March 31, 2019 2018 Gross loss and loss expense reserves, beginning of period $ 5,646 $ 5,219 Less reinsurance recoverable 238 187 Net loss and loss expense reserves, beginning of period 5,408 5,032 Net loss and loss expense reserves related to acquisition of MSP at February 28, 2019 246 — Net incurred loss and loss expenses related to: Current accident year 857 839 Prior accident years (67 ) (48 ) Total incurred 790 791 Net paid loss and loss expenses related to: Current accident year 177 195 Prior accident years 647 519 Total paid 824 714 Net loss and loss expense reserves, end of period 5,620 5,109 Plus reinsurance recoverable 266 184 Gross loss and loss expense reserves, end of period $ 5,886 $ 5,293

Life Policy and Investment Co_2

Life Policy and Investment Contract Reserves (Tables)	3 Months Ended
	Mar. 31, 2019
Liability for Future Policy Benefits [Abstract]
Reserve For Losses Loss Adjustment Expenses Table [Text Block]	This table summarizes our life policy and investment contract reserves: (Dollars in millions) March 31, December 31, 2018 Life policy reserves: Ordinary/traditional life $ 1,168 $ 1,149 Other 48 48 Subtotal 1,216 1,197 Investment contract reserves: Deferred annuities 776 787 Universal life 632 632 Structured settlements 154 156 Other 6 7 Subtotal 1,568 1,582 Total life policy and investment contract reserves $ 2,784 $ 2,779

Deferred Acquisition Costs (Ta

Deferred Acquisition Costs (Tables)	3 Months Ended
	Mar. 31, 2019
Deferred Costs [Abstract]
Deferred Policy Acquisition Costs And Asset Reconciliation, Including the Amortized Deferred Policy Acquisition Costs	The table below shows the deferred policy acquisition costs and asset reconciliation. (Dollars in millions) Three months ended March 31, 2019 2018 Property casualty: Deferred policy acquisition costs asset, beginning of period $ 464 $ 438 Capitalized deferred policy acquisition costs 254 232 Amortized deferred policy acquisition costs (233 ) (224 ) Deferred policy acquisition costs asset, end of period $ 485 $ 446 Life: Deferred policy acquisition costs asset, beginning of period $ 274 $ 232 Capitalized deferred policy acquisition costs 16 13 Amortized deferred policy acquisition costs (13 ) (10 ) Shadow deferred policy acquisition costs (11 ) 10 Deferred policy acquisition costs asset, end of period $ 266 $ 245 Consolidated: Deferred policy acquisition costs asset, beginning of period $ 738 $ 670 Capitalized deferred policy acquisition costs 270 245 Amortized deferred policy acquisition costs (246 ) (234 ) Shadow deferred policy acquisition costs (11 ) 10 Deferred policy acquisition costs asset, end of period $ 751 $ 691

Accumulated Other Comprehensi_2

Accumulated Other Comprehensive Income (Tables)	3 Months Ended
	Mar. 31, 2019
Accumulated Other Comprehensive Income [Abstract]
Schedule of Accumulated Other Comprehensive Income (Loss)	(Dollars in millions) Three months ended March 31, 2019 2018 Before tax Income tax Net Before tax Income tax Net Investments: AOCI, beginning of period $ 46 $ 9 $ 37 $ 3,540 $ 733 $ 2,807 Cumulative effect of change in accounting for equity securities as of January 1, 2018 — — — (3,155 ) (652 ) (2,503 ) Adjusted AOCI, beginning of period 46 9 37 385 81 304 OCI before investment gains and losses, net, recognized in net income 244 51 193 (217 ) (45 ) (172 ) Investment gains and losses, net, recognized in net income (2 ) (1 ) (1 ) (4 ) (1 ) (3 ) OCI 242 50 192 (221 ) (46 ) (175 ) AOCI, end of period $ 288 $ 59 $ 229 $ 164 $ 35 $ 129 Pension obligations: AOCI, beginning of period $ (16 ) $ (2 ) $ (14 ) $ (12 ) $ (1 ) $ (11 ) OCI excluding amortization recognized in net income — — — — — — Amortization recognized in net income — — — — — — OCI — — — — — — AOCI, end of period $ (16 ) $ (2 ) $ (14 ) $ (12 ) $ (1 ) $ (11 ) Life deferred acquisition costs, life policy reserves and other: AOCI, beginning of period $ (1 ) $ — $ (1 ) $ (10 ) $ (2 ) $ (8 ) OCI before investment gains and losses, net, recognized in net income — — — 6 1 5 Investment gains and losses, net, recognized in net income (5 ) (1 ) (4 ) — — — OCI (5 ) (1 ) (4 ) 6 1 5 AOCI, end of period $ (6 ) $ (1 ) $ (5 ) $ (4 ) $ (1 ) $ (3 ) Summary of AOCI: AOCI, beginning of period $ 29 $ 7 $ 22 $ 3,518 $ 730 $ 2,788 Cumulative effect of change in accounting for equity securities as of January 1, 2018 — — — (3,155 ) (652 ) (2,503 ) Adjusted AOCI, beginning of period 29 7 22 363 78 285 Investments OCI 242 50 192 (221 ) (46 ) (175 ) Pension obligations OCI — — — — — — Life deferred acquisition costs, life policy reserves and other OCI (5 ) (1 ) (4 ) 6 1 5 Total OCI 237 49 188 (215 ) (45 ) (170 ) AOCI, end of period $ 266 $ 56 $ 210 $ 148 $ 33 $ 115

Reinsurance (Tables)

Reinsurance (Tables)	3 Months Ended
	Mar. 31, 2019
Reinsurance Disclosures [Abstract]
Property Casualty Insurance Assumed And Ceded Business	The table below summarizes our consolidated property casualty insurance net written premiums, earned premiums and incurred loss and loss expenses: (Dollars in millions) Three months ended March 31, 2019 2018 Direct written premiums $ 1,335 $ 1,247 Assumed written premiums 87 49 Ceded written premiums (41 ) (38 ) Net written premiums $ 1,381 $ 1,258 Direct earned premiums $ 1,266 $ 1,207 Assumed earned premiums 43 33 Ceded earned premiums (42 ) (40 ) Earned premiums $ 1,267 $ 1,200 Direct incurred loss and loss expenses $ 787 $ 781 Assumed incurred loss and loss expenses 25 16 Ceded incurred loss and loss expenses (22 ) (6 ) Incurred loss and loss expenses $ 790 $ 791
Life Insurance Assumed and Ceded Business	(Dollars in millions) Three months ended March 31, 2019 2018 Direct earned premiums $ 83 $ 77 Ceded earned premiums (17 ) (17 ) Earned premiums $ 66 $ 60 Direct contract holders' benefits incurred 85 76 Ceded contract holders' benefits incurred (15 ) (13 ) Contract holders' benefits incurred $ 70 $ 63

Income Taxes (Tables)

Income Taxes (Tables)	3 Months Ended
	Mar. 31, 2019
Income Tax Disclosure [Abstract]
Differences Between The 35 Percent Statutory Income Tax Rate And Effective Income Tax Rate	The differences between the 21 % statutory federal income tax rate and our effective income tax rate were as follows: (Dollars in millions) Three months ended March 31, 2019 2018 Tax at statutory rate: $ 182 21.0 % $ (11 ) 21.0 % Increase (decrease) resulting from: Tax-exempt income from municipal bonds (5 ) (0.6 ) (5 ) 10.0 Dividend received exclusion (4 ) (0.5 ) (3 ) 6.0 Other (1 ) (0.1 ) — 1.0 Provision for income taxes $ 172 19.8 % $ (19 ) 38.0 %

Net Income Per Common Share (Ta

Net Income Per Common Share (Tables)	3 Months Ended
	Mar. 31, 2019
Earnings Per Share [Abstract]
Calculations For Basic And Diluted Earnings Per Share	The table shows calculations for basic and diluted earnings per share: (In millions, except per share data) Three months ended March 31, 2019 2018 Numerator: Net income (loss)—basic and diluted $ 695 $ (31 ) Denominator: Basic weighted-average common shares outstanding 163.0 164.0 Effect of share-based awards: Stock options 0.9 — Nonvested shares 0.7 — Diluted weighted-average shares 164.6 164.0 Earnings per share: Basic $ 4.27 $ (0.19 ) Diluted $ 4.22 $ (0.19 ) Number of anti-dilutive share-based awards 0.7 2.8

Employee Retirement Benefits (T

Employee Retirement Benefits (Tables)	3 Months Ended
	Mar. 31, 2019
Retirement Benefits [Abstract]
Schedule of Defined Benefit Plans Disclosures	The following summarizes the components of net periodic benefit cost for our qualified and supplemental pension plans: (Dollars in millions) Three months ended March 31, 2019 2018 Service cost $ 2 $ 3 Non-service costs (benefit): Interest cost 3 3 Expected return on plan assets (5 ) (5 ) Amortization of actuarial loss and prior service cost — — Other 1 — Total non-service benefit (1 ) (2 ) Net periodic benefit cost $ 1 $ 1

Segment Information (Tables)

Segment Information (Tables)	3 Months Ended
	Mar. 31, 2019
Segment Reporting [Abstract]
Segment Information	Segment information is summarized in the following table: (Dollars in millions) Three months ended March 31, 2019 2018 Revenues: Commercial lines insurance Commercial casualty $ 268 $ 265 Commercial property 234 228 Commercial auto 170 161 Workers' compensation 77 80 Other commercial 61 56 Commercial lines insurance premiums 810 790 Fee revenues 1 2 Total commercial lines insurance 811 792 Personal lines insurance Personal auto 155 151 Homeowner 147 136 Other personal 42 38 Personal lines insurance premiums 344 325 Fee revenues 1 1 Total personal lines insurance 345 326 Excess and surplus lines insurance 63 56 Fee revenues 1 — Total excess and surplus lines insurance 64 56 Life insurance premiums 66 60 Fee revenues 1 1 Total life insurance 67 61 Investments Investment income, net of expenses 157 150 Investment gains and losses, net 663 (191 ) Total investment revenue 820 (41 ) Other Earned premiums 50 29 Other 2 1 Total other revenues 52 30 Total revenues $ 2,159 $ 1,224 Income (loss) before income taxes: Insurance underwriting results Commercial lines insurance $ 76 $ 15 Personal lines insurance (4 ) (9 ) Excess and surplus lines insurance 11 18 Life insurance (1 ) 2 Investments 796 (65 ) Other (11 ) (11 ) $ 867 $ (50 ) Identifiable assets: March 31, December 31, 2018 Property casualty insurance $ 3,308 $ 3,285 Life insurance 1,472 1,424 Investments 17,738 16,741 Other 834 485 Total $ 23,352 $ 21,935

Accounting Policies (Details)

Accounting Policies (Details)	3 Months Ended
	Mar. 31, 2019
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease, term of contract	5 years
Minimum [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Finance lease, term of contract	3 years
Maximum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Finance lease, term of contract	6 years

Investments - Analysis of Cost

Investments - Analysis of Cost or Amortized Cost, Gross Unrealized Gains and Losses and Fair Value for Investments (Detail) - Debt Securities - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	$ 10,734	$ 10,643
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax	320	174
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	32	128
Fair Value	11,022	10,689
Corporate
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	5,753	5,712
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax	160	85
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	25	87
Fair Value	5,888	5,710
States, municipalities and political subdivisions
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	4,269	4,251
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax	153	84
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	3	31
Fair Value	4,419	4,304
Government-sponsored enterprises
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	305	316
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax	0	1
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	3	7
Fair Value	302	310
Commercial mortgage-backed
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	292	287
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax	6	3
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	1	2
Fair Value	297	288
United States government
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	99	67
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax	1	1
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	0	1
Fair Value	100	67
Foreign government
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	16	10
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax	0	0
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	0	0
Fair Value	$ 16	$ 10

Investments - Fair Values and U

Investments - Fair Values and Unrealized Losses by Investment Category and by Duration of Securities' Continuous Unrealized Loss Position (Detail) - Fixed maturities - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Investments, Unrealized Loss Position [Line Items]
Less than 12 months Fair Value	$ 362	$ 3,031
Less than 12 months Unrealized Losses	5	70
12 months or more Fair Value	1,194	1,149
12 months or more Unrealized Losses	27	58
Total Fair Value	1,556	4,180
Total Unrealized Losses	32	128
Corporate
Investments, Unrealized Loss Position [Line Items]
Less than 12 months Fair Value	343	2,082
Less than 12 months Unrealized Losses	5	51
12 months or more Fair Value	685	501
12 months or more Unrealized Losses	20	36
Total Fair Value	1,028	2,583
Total Unrealized Losses	25	87
States, municipalities and political subdivisions
Investments, Unrealized Loss Position [Line Items]
Less than 12 months Fair Value	10	823
Less than 12 months Unrealized Losses	0	18
12 months or more Fair Value	237	340
12 months or more Unrealized Losses	3	13
Total Fair Value	247	1,163
Total Unrealized Losses	3	31
Government-sponsored enterprises
Investments, Unrealized Loss Position [Line Items]
Less than 12 months Fair Value	7	49
Less than 12 months Unrealized Losses	0	1
12 months or more Fair Value	204	211
12 months or more Unrealized Losses	3	6
Total Fair Value	211	260
Total Unrealized Losses	3	7
Commercial mortgage-backed
Investments, Unrealized Loss Position [Line Items]
Less than 12 months Fair Value	2	77
Less than 12 months Unrealized Losses	0	0
12 months or more Fair Value	45	64
12 months or more Unrealized Losses	1	2
Total Fair Value	47	141
Total Unrealized Losses	1	2
United States government
Investments, Unrealized Loss Position [Line Items]
Less than 12 months Fair Value	0	0
Less than 12 months Unrealized Losses	0	0
12 months or more Fair Value	23	33
12 months or more Unrealized Losses	0	1
Total Fair Value	23	33
Total Unrealized Losses	$ 0	$ 1

Investments - Schedule of Contr

Investments - Schedule of Contractual Maturities of Investments (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Amortized cost
Due in one year or less	$ 598
Due after one year through five years	2,977
Due after five years through ten years	3,656
Due after ten years	3,503
Total	10,734	$ 10,643
Fair value
Due in one year or less	604
Due after one year through five years	3,039
Due after five years through ten years	3,742
Due after ten years	3,637
Total	$ 11,022	$ 10,689
% of fair value
Due in one year or less	5.50%
Due after one year through five years	27.60%
Due after five years through ten years	33.90%
Due after ten years	33.00%
Total	100.00%

Investments - Realized Investme

Investments - Realized Investment Gains and Losses and Change in Unrealized Investment Gains and Losses and Other Items (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Investment income:
Interest	$ 111	$ 110
Dividends	46	42
Other	3	1
Total	160	153
Less investment expenses	3	3
Total	157	150
Gain (Loss) on Sale of Investments	660	(191)
Investment gains and losses, net:
Investment gains and losses, net	663	(191)
Equity securities
Investment income:
Gain (Loss) on Sale of Investments	4	3
Unrealized Gain (Loss) on Investments	652	(198)
Investment gains and losses, net:
Other	5	0
Investment gains and losses, net	656	(195)
Fixed maturities
Investment gains and losses, net:
Gross realized gains	2	4
Investment gains and losses, net	$ 2	$ 4

Investments - Additional Inform

Investments - Additional Information (Detail)	3 Months Ended		12 Months Ended
	Mar. 31, 2019USD ($)security	Mar. 31, 2018USD ($)security	Dec. 31, 2018USD ($)security
Gain (Loss) on Investments [Line Items]
Largest Single Common Stock Holding | $	$ 296,000,000
Largest equity holdings to total equity portfolio	4.60%
Largest equity holdings to total portfolio	1.70%
Fixed maturity investments, Percentage of amortized costs	70.00%		70.00%
Fixed maturities
Gain (Loss) on Investments [Line Items]
Number Of Securities Other Than Temporary Impairment Losses1 | security	0	0
Provision for Other Credit Losses | $	$ 0	$ 0
Number Of Securities Continuous Unrealized Loss Position More Than Twelve Months | security	358		400
Unrealized losses 12 months or more (equity investment less than $500,000) | $	$ (27,000,000)		$ (58,000,000)
Number Of Securities Continuous Unrealized Loss Position More Than Twelve Months and Below 70 Percent of Amortized Cost	0		0
Equity securities
Gain (Loss) on Investments [Line Items]
Number Of Securities Other Than Temporary Impairment Losses1 | security		0

Fair Value Measurements - Fair

Fair Value Measurements - Fair Value Hierarchy for Assets Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value	$ 11,022	$ 10,689
Equity securities, at fair value	6,571	5,920
Separate accounts	831	803
Top Hat savings plan mutual funds and common equity (included in Other assets)	38	34
Fair value of asset	18,451	17,434
Debt Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value	11,022	10,689
Debt Securities | Corporate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value	5,888	5,710
Debt Securities | States, municipalities and political subdivisions
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value	4,419	4,304
Debt Securities | Government-sponsored enterprises
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value	302	310
Debt Securities | Commercial mortgage-backed
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value	297	288
Debt Securities | United States government
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value	100	67
Debt Securities | Foreign government
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value	16	10
Equity securities | Common equities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities, at fair value	6,381	5,742
Equity securities | Nonredeemable preferred equities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities, at fair value	190	178
Taxable Fixed Maturities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Separate accounts	820	791
Quoted prices in active markets for identical assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Top Hat savings plan mutual funds and common equity (included in Other assets)	38	34
Fair value of asset	6,519	5,843
Quoted prices in active markets for identical assets (Level 1) | Debt Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value	100	67
Quoted prices in active markets for identical assets (Level 1) | Debt Securities | Corporate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value	0	0
Quoted prices in active markets for identical assets (Level 1) | Debt Securities | States, municipalities and political subdivisions
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value	0	0
Quoted prices in active markets for identical assets (Level 1) | Debt Securities | Government-sponsored enterprises
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value	0	0
Quoted prices in active markets for identical assets (Level 1) | Debt Securities | Commercial mortgage-backed
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value	0	0
Quoted prices in active markets for identical assets (Level 1) | Debt Securities | United States government
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value	100	67
Quoted prices in active markets for identical assets (Level 1) | Debt Securities | Foreign government
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value	0	0
Quoted prices in active markets for identical assets (Level 1) | Equity securities | Common equities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities, at fair value	6,381	5,742
Quoted prices in active markets for identical assets (Level 1) | Equity securities | Nonredeemable preferred equities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities, at fair value	0	0
Quoted prices in active markets for identical assets (Level 1) | Taxable Fixed Maturities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Separate accounts	0	0
Significant other observable inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Top Hat savings plan mutual funds and common equity (included in Other assets)	0	0
Fair value of asset	11,927	11,586
Significant other observable inputs (Level 2) | Debt Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value	10,917	10,617
Significant other observable inputs (Level 2) | Debt Securities | Corporate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value	5,887	5,709
Significant other observable inputs (Level 2) | Debt Securities | States, municipalities and political subdivisions
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value	4,415	4,300
Significant other observable inputs (Level 2) | Debt Securities | Government-sponsored enterprises
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value	302	310
Significant other observable inputs (Level 2) | Debt Securities | Commercial mortgage-backed
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value	297	288
Significant other observable inputs (Level 2) | Debt Securities | United States government
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value	0	0
Significant other observable inputs (Level 2) | Debt Securities | Foreign government
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value	16	10
Significant other observable inputs (Level 2) | Equity securities | Common equities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities, at fair value	0	0
Significant other observable inputs (Level 2) | Equity securities | Nonredeemable preferred equities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities, at fair value	190	178
Significant other observable inputs (Level 2) | Taxable Fixed Maturities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Separate accounts	820	791
Significant unobservable inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Top Hat savings plan mutual funds and common equity (included in Other assets)	0	0
Fair value of asset	5	5
Significant unobservable inputs (Level 3) | Debt Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value	5	5
Significant unobservable inputs (Level 3) | Debt Securities | Corporate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value	1	1
Significant unobservable inputs (Level 3) | Debt Securities | States, municipalities and political subdivisions
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value	4	4
Significant unobservable inputs (Level 3) | Debt Securities | Government-sponsored enterprises
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value	0	0
Significant unobservable inputs (Level 3) | Debt Securities | Commercial mortgage-backed
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value	0	0
Significant unobservable inputs (Level 3) | Debt Securities | United States government
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value	0	0
Significant unobservable inputs (Level 3) | Debt Securities | Foreign government
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value	0	0
Significant unobservable inputs (Level 3) | Equity securities | Common equities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities, at fair value	0	0
Significant unobservable inputs (Level 3) | Equity securities | Nonredeemable preferred equities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities, at fair value	0	0
Significant unobservable inputs (Level 3) | Taxable Fixed Maturities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Separate accounts	$ 0	$ 0

Fair Value Measurements - Chang

Fair Value Measurements - Change in Level 3 Assets (Detail) - 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]
Beginning balance	$ 5	$ 6
Total gains or losses (realized/unrealized):
Included in net income	0	0
Included in other comprehensive income	0	(1)
Purchases	0	0
Sales	0	0
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Ending balance	5	5
Corporate Fixed Maturities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	1	1
Total gains or losses (realized/unrealized):
Included in net income	0	0
Included in other comprehensive income	0	0
Purchases	0	0
Sales	0	0
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Ending balance	1	1
States, Municipalities And Political Subdivisions Fixed Maturities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	4	5
Total gains or losses (realized/unrealized):
Included in net income	0	0
Included in other comprehensive income	0	(1)
Purchases	0	0
Sales	0	0
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Ending balance	$ 4	$ 4

Fair Value Measurements - Summa

Fair Value Measurements - Summary of Book Value and Principal Amounts of Long-Term Debt (Detail) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Book value	$ 788	$ 788
Principal amount of debt	$ 793	$ 793
Senior Debentures 6.900% Due 2028
Debt Instrument [Line Items]
Interest rate	6.90%	6.90%
Debt issuance year	1998	1998
Book value	$ 27	$ 27
Principal amount of debt	$ 28	$ 28
Senior Debentures 6.920% Due 2028
Debt Instrument [Line Items]
Interest rate	6.92%	6.92%
Debt issuance year	2005	2005
Book value	$ 391	$ 391
Principal amount of debt	$ 391	$ 391
Senior Notes 6.125% Due 2034
Debt Instrument [Line Items]
Interest rate	6.125%	6.125%
Debt issuance year	2004	2004
Book value	$ 370	$ 370
Principal amount of debt	$ 374	$ 374

Fair Value Measurements - Fai_2

Fair Value Measurements - Fair Values of Note Payable and Long-Term Debt (Detail) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of note payable	$ 32	$ 32
Total	$ 1,010	$ 975
Senior Debentures 6.900 % Due 2028
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest rate	6.90%	6.90%
Debt instrument, year of maturity	2028	2028
Fair value of senior debt	$ 33	$ 32
Senior Debentures 6.920 % Due 2028
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest rate	6.92%	6.92%
Debt instrument, year of maturity	2028	2028
Fair value of senior debt	$ 486	$ 471
Senior Notes 6.125 % Due 2034
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest rate	6.125%	6.125%
Debt instrument, year of maturity	2034	2034
Fair value of senior debt	$ 459	$ 440
Quoted prices in active markets for identical assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of note payable	0	0
Total	0	0
Quoted prices in active markets for identical assets (Level 1) | Senior Debentures 6.900 % Due 2028
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of senior debt	0	0
Quoted prices in active markets for identical assets (Level 1) | Senior Debentures 6.920 % Due 2028
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of senior debt	0	0
Quoted prices in active markets for identical assets (Level 1) | Senior Notes 6.125 % Due 2034
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of senior debt	0	0
Significant other observable inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of note payable	32	32
Total	1,010	975
Significant other observable inputs (Level 2) | Senior Debentures 6.900 % Due 2028
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of senior debt	33	32
Significant other observable inputs (Level 2) | Senior Debentures 6.920 % Due 2028
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of senior debt	486	471
Significant other observable inputs (Level 2) | Senior Notes 6.125 % Due 2034
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of senior debt	459	440
Significant unobservable inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of note payable	0	0
Total	0	0
Significant unobservable inputs (Level 3) | Senior Debentures 6.900 % Due 2028
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of senior debt	0	0
Significant unobservable inputs (Level 3) | Senior Debentures 6.920 % Due 2028
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of senior debt	0	0
Significant unobservable inputs (Level 3) | Senior Notes 6.125 % Due 2034
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of senior debt	$ 0	$ 0

Fair Value Measurements - Fai_3

Fair Value Measurements - Fair Value of Life Policy Loans, Deferred Annuities, and Structured Settlements (Detail) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of life policy loans	$ 41	$ 40
Liabilities Related to Investment Contracts, Fair Value Disclosure	946	927
Quoted prices in active markets for identical assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of life policy loans	0	0
Liabilities Related to Investment Contracts, Fair Value Disclosure	0	0
Significant other observable inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of life policy loans	0	0
Liabilities Related to Investment Contracts, Fair Value Disclosure	195	185
Significant unobservable inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of life policy loans	41	40
Liabilities Related to Investment Contracts, Fair Value Disclosure	751	742
Deferred annuities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities Related to Investment Contracts, Fair Value Disclosure	751	742
Deferred annuities | Quoted prices in active markets for identical assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities Related to Investment Contracts, Fair Value Disclosure	0	0
Deferred annuities | Significant other observable inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities Related to Investment Contracts, Fair Value Disclosure	0	0
Deferred annuities | Significant unobservable inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities Related to Investment Contracts, Fair Value Disclosure	751	742
Structured settlements
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities Related to Investment Contracts, Fair Value Disclosure	195	185
Structured settlements | Quoted prices in active markets for identical assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities Related to Investment Contracts, Fair Value Disclosure	0	0
Structured settlements | Significant other observable inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities Related to Investment Contracts, Fair Value Disclosure	195	185
Structured settlements | Significant unobservable inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities Related to Investment Contracts, Fair Value Disclosure	$ 0	$ 0

Fair Value Measurements - Addit

Fair Value Measurements - Additional Information (Detail) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Finance receivable	$ 72	$ 71
Loss and loss expense reserves	5,944	5,707
Life Policy Loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Finance receivable	32	33
Deferred annuities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loss and loss expense reserves	776	787
Structured settlements
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loss and loss expense reserves	$ 154	$ 156
Maximum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Percentage Of Level 3 Assets To Total Financial Instruments Measured At Fair Value	1.00%

Property Casualty Loss and Lo_3

Property Casualty Loss and Loss Expenses - Consolidated Property Casualty Loss and Loss Expense Reserves (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Feb. 28, 2019
Summary of Consolidated Property Casualty Loss and Loss Expense Reserves [Roll Forward]
Gross loss and loss expense reserves, beginning of period	$ 5,646	$ 5,219
Less reinsurance recoverable	238	187
Net loss and loss expense reserves, beginning of period	5,408	5,032
Current accident year	857	839
Prior accident years	(67)	(48)
Total incurred	790	791
Current accident year	177	195
Prior accident years	647	519
Total paid	824	714
Net loss and loss expense reserves, end of period	5,620	5,109
Plus reinsurance recoverable	266	184
Gross loss and loss expense reserves, end of period	$ 5,886	$ 5,293
MSP Underwriting Limited
Summary of Consolidated Property Casualty Loss and Loss Expense Reserves [Roll Forward]
Net loss and loss expense reserves related to acquisition of MSP at February 28, 2019			$ 246

Property Casualty Loss and Lo_4

Property Casualty Loss and Loss Expenses - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018	Dec. 31, 2017
Supplemental Information for Property, Casualty Insurance Underwriters [Line Items]
Reserve for loss and loss expenses	$ 5,886	$ 5,293	$ 5,646	$ 5,219
Prior accident years	(67)	(48)
Life and Health Loss Reserves
Supplemental Information for Property, Casualty Insurance Underwriters [Line Items]
Reserve for loss and loss expenses	58	52
Commercial Lines
Supplemental Information for Property, Casualty Insurance Underwriters [Line Items]
Prior accident years	(62)	(35)
Commercial Lines | Workers' Compensation
Supplemental Information for Property, Casualty Insurance Underwriters [Line Items]
Prior accident years	(15)	(13)
Commercial Lines | Commercial Casualty Segment [Member]
Supplemental Information for Property, Casualty Insurance Underwriters [Line Items]
Prior accident years	(31)	5
Commercial Lines | Other Commercial Lines [Member]
Supplemental Information for Property, Casualty Insurance Underwriters [Line Items]
Prior accident years		(4)
Commercial Lines | Commercial Auto
Supplemental Information for Property, Casualty Insurance Underwriters [Line Items]
Prior accident years	(11)	(2)
Commercial Lines | Commercial Property Segment [Member]
Supplemental Information for Property, Casualty Insurance Underwriters [Line Items]
Prior accident years		(21)
Personal Lines
Supplemental Information for Property, Casualty Insurance Underwriters [Line Items]
Prior accident years	3	(1)
Personal Lines | Homeowner [Member]
Supplemental Information for Property, Casualty Insurance Underwriters [Line Items]
Prior accident years	11
Excess and Surplus Lines Insurance
Supplemental Information for Property, Casualty Insurance Underwriters [Line Items]
Prior accident years	$ (2)	(10)
Reinsurance assumed and other non segment [Member]
Supplemental Information for Property, Casualty Insurance Underwriters [Line Items]
Prior accident years		(2)
Consolidated Property and Casualty Insurance Entity | Catastrophe Development
Supplemental Information for Property, Casualty Insurance Underwriters [Line Items]
Prior accident years		$ (7)

Reserves in Addition to Account

Reserves in Addition to Account Balance, Based on Expected No-Lapse Guarantee Benefits and Expected Policy Assessments (Detail) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Liability for Future Policy Benefit, by Product Segment [Line Items]
Life policy and investment contract reserves	$ 2,784	$ 2,779
Life policy reserves:
Liability for Future Policy Benefit, by Product Segment [Line Items]
Life policy and investment contract reserves	1,216	1,197
Life policy reserves: | Ordinary/traditional life
Liability for Future Policy Benefit, by Product Segment [Line Items]
Life policy and investment contract reserves	1,168	1,149
Life policy reserves: | Other
Liability for Future Policy Benefit, by Product Segment [Line Items]
Life policy and investment contract reserves	48	48
Investment contract reserves:
Liability for Future Policy Benefit, by Product Segment [Line Items]
Life policy and investment contract reserves	1,568	1,582
Investment contract reserves: | Deferred annuities
Liability for Future Policy Benefit, by Product Segment [Line Items]
Life policy and investment contract reserves	776	787
Investment contract reserves: | Universal life
Liability for Future Policy Benefit, by Product Segment [Line Items]
Life policy and investment contract reserves	632	632
Investment contract reserves: | Structured Settlement Annuity [Member]
Liability for Future Policy Benefit, by Product Segment [Line Items]
Life policy and investment contract reserves	154	156
Investment contract reserves: | Other
Liability for Future Policy Benefit, by Product Segment [Line Items]
Life policy and investment contract reserves	$ 6	$ 7

Deferred Acquisition Costs - De

Deferred Acquisition Costs - Deferred Policy Acquisition Costs and Asset Reconciliation (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Movement Analysis of Deferred Policy Acquisition Costs [Roll Forward]
Deferred policy acquisition costs asset, beginning of period	$ 738	$ 670
Capitalized deferred policy acquisition costs	270	245
Deferred Policy Acquisition Costs, Amortization Expense	(246)	(234)
Deferred Policy Acquisition Cost, Amortization Expense, Other	(11)	10
Deferred policy acquisition costs asset, end of period	751	691
Consolidated Property and Casualty Insurance Entity
Movement Analysis of Deferred Policy Acquisition Costs [Roll Forward]
Deferred policy acquisition costs asset, beginning of period	464	438
Capitalized deferred policy acquisition costs	254	232
Deferred Policy Acquisition Costs, Amortization Expense	(233)	(224)
Deferred policy acquisition costs asset, end of period	485	446
Life Insurance Segment
Movement Analysis of Deferred Policy Acquisition Costs [Roll Forward]
Deferred policy acquisition costs asset, beginning of period	274	232
Capitalized deferred policy acquisition costs	16	13
Deferred Policy Acquisition Costs, Amortization Expense	(13)	(10)
Deferred Policy Acquisition Cost, Amortization Expense, Other	(11)	10
Deferred policy acquisition costs asset, end of period	$ 266	$ 245

Accumulated Other Comprehensi_3

Accumulated Other Comprehensive Income (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Accumulated other comprehensive income, net of tax, beginning of period	$ 210		$ 210	$ 22
Accumulated other comprehensive income, net of tax, end of period	210
Accumulated Net Unrealized Investment Gain (Loss)
Accumulated Other Comprehensive Income Loss Before Tax [Abstract]
Accumulated other comprehensive income, before tax, beginning of period	46	$ 385
Cumulative effect of change in accounting for equity securities, before tax				0	$ (3,155)
Other comprehensive income before reclassification, before tax	244	(217)
Reclassification adjustment, before tax	(2)	(4)
Effect on other comprehensive income, before tax	242	(221)
Accumulated other comprehensive income, before tax, end of period	288	164
Accumulated Other Comprehensive Income (Loss), Tax [Abstract]
Accumulated other comprehensive income, tax, beginning of period	9	81
Cumulative effect of change in accounting for equity securities, tax				0	(652)
Other comprehensive income before reclassification, tax	51	(45)
Reclassification adjustment, tax	(1)	(1)
Effect on other comprehensive income, tax	50	(46)
Accumulated other comprehensive income, tax, end of period	59	35
Unrealized gains reclassified to retained earnings for ASU 2016-01, after tax				0	(2,503)
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Accumulated other comprehensive income, net of tax, beginning of period	229	129	229	37	304
Other comprehensive income before reclassification, net of tax	193	(172)
Reclassification adjustment, net of tax	(1)	(3)
Effect on other comprehensive income, net of tax	192	(175)
Accumulated other comprehensive income, net of tax, end of period	229	129
Accumulated Defined Benefit Plans Adjustment
Accumulated Other Comprehensive Income Loss Before Tax [Abstract]
Accumulated other comprehensive income, before tax, beginning of period	(16)	(12)
Other comprehensive income before reclassification, before tax	0	0
Reclassification adjustment, before tax	0	0
Effect on other comprehensive income, before tax	0	0
Accumulated other comprehensive income, before tax, end of period	(16)	(12)
Accumulated Other Comprehensive Income (Loss), Tax [Abstract]
Accumulated other comprehensive income, tax, beginning of period	(2)	(1)
Other comprehensive income before reclassification, tax	0	0
Reclassification adjustment, tax	0	0
Effect on other comprehensive income, tax	0	0
Accumulated other comprehensive income, tax, end of period	(2)	(1)
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Accumulated other comprehensive income, net of tax, beginning of period	(14)	(11)	(14)	(14)	(11)
Other comprehensive income before reclassification, net of tax	0	0
Reclassification adjustment, net of tax	0	0
Effect on other comprehensive income, net of tax	0	0
Accumulated other comprehensive income, net of tax, end of period	(14)	(11)
Accumulated Net Unrealized Gain (Loss) on Deferred Costs, Reserves And Other
Accumulated Other Comprehensive Income Loss Before Tax [Abstract]
Accumulated other comprehensive income, before tax, beginning of period	(1)	(10)
Other comprehensive income before reclassification, before tax	0	6
Reclassification adjustment, before tax	(5)	0
Effect on other comprehensive income, before tax	(5)	6
Accumulated other comprehensive income, before tax, end of period	(6)	(4)
Accumulated Other Comprehensive Income (Loss), Tax [Abstract]
Accumulated other comprehensive income, tax, beginning of period	0	(2)
Other comprehensive income before reclassification, tax	0	1
Reclassification adjustment, tax	(1)	0
Effect on other comprehensive income, tax	(1)	1
Accumulated other comprehensive income, tax, end of period	(1)	(1)
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Accumulated other comprehensive income, net of tax, beginning of period	(5)	(3)	(5)	(1)	(8)
Other comprehensive income before reclassification, net of tax	0	5
Reclassification adjustment, net of tax	(4)	0
Effect on other comprehensive income, net of tax	(4)	5
Accumulated other comprehensive income, net of tax, end of period	(5)	(3)
Accumulated Other Comprehensive Income (Loss)
Accumulated Other Comprehensive Income Loss Before Tax [Abstract]
Accumulated other comprehensive income, before tax, beginning of period	29	363
Cumulative effect of change in accounting for equity securities, before tax				0	(3,155)
Change in unrealized gains, net, on investments available for sale, before tax	242	(221)
Change in pension obligations, before tax	0	0
Change in life deferred acquisition costs, life policy reserves and other, before tax	(5)	6
Effect on other comprehensive income, before tax	237	(215)
Accumulated other comprehensive income, before tax, end of period	266	148
Accumulated Other Comprehensive Income (Loss), Tax [Abstract]
Accumulated other comprehensive income, tax, beginning of period	7	78
Cumulative effect of change in accounting for equity securities, tax				0	(652)
Change in unrealized gains, net, on investments available for sale, tax	50	(46)
Change in pension obligations, tax	0	0
Change in life deferred acquisition costs, life policy reserves and other, tax	(1)	1
Effect on other comprehensive income, tax	49	(45)
Accumulated other comprehensive income, tax, end of period	56	33
Unrealized gains reclassified to retained earnings for ASU 2016-01, after tax			0	0	(2,503)
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Accumulated other comprehensive income, net of tax, beginning of period	210	115	$ 210	22	285
Cumulative effect of change in accounting for equity securities, net					(2,503)
Change in unrealized gains, net, on investments available for sale, net of tax	192	(175)
Change in pension obligations, net of tax	0	0
Change in life deferred acquisition costs, life policy reserves and other, net of tax	(4)	5
Effect on other comprehensive income, net of tax	188	(170)
Accumulated other comprehensive income, net of tax, end of period	210	115
Previously Reported | Accumulated Net Unrealized Investment Gain (Loss)
Accumulated Other Comprehensive Income Loss Before Tax [Abstract]
Accumulated other comprehensive income, before tax, beginning of period	46	3,540
Accumulated Other Comprehensive Income (Loss), Tax [Abstract]
Accumulated other comprehensive income, tax, beginning of period	9	733
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Accumulated other comprehensive income, net of tax, beginning of period				37	2,807
Previously Reported | Accumulated Other Comprehensive Income (Loss)
Accumulated Other Comprehensive Income Loss Before Tax [Abstract]
Accumulated other comprehensive income, before tax, beginning of period	29	3,518
Accumulated Other Comprehensive Income (Loss), Tax [Abstract]
Accumulated other comprehensive income, tax, beginning of period	$ 7	$ 730
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Accumulated other comprehensive income, net of tax, beginning of period				$ 22	$ 2,788

Reinsurance - Consolidated Prop

Reinsurance - Consolidated Property Casualty Insurance Assumed and Ceded Business (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Property Casualty Insurance Assumed And Ceded Business [Line Items]
Incurred loss and loss expenses	$ 860	$ 854
Consolidated Property and Casualty Insurance Entity
Property Casualty Insurance Assumed And Ceded Business [Line Items]
Direct written premiums	1,335	1,247
Assumed written premiums	87	49
Ceded written premiums	(41)	(38)
Net written premiums	1,381	1,258
Direct earned premiums	1,266	1,207
Assumed earned premiums	43	33
Ceded earned premiums	(42)	(40)
Earned premiums	1,267	1,200
Direct incurred loss and loss expenses	787	781
Assumed incurred loss and loss expenses	25	16
Ceded incurred loss and loss expenses	(22)	(6)
Incurred loss and loss expenses	$ 790	$ 791

Reinsurance - Life Insurance Ce

Reinsurance - Life Insurance Ceded Business (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Reinsurance for Insurance Companies, by Product Segment [Line Items]
Insurance losses and contract holders' benefits	$ 860	$ 854
Life Insurance Segment
Reinsurance for Insurance Companies, by Product Segment [Line Items]
Direct earned premiums	83	77
Ceded earned premiums	(17)	(17)
Earned premiums	66	60
Direct contract holders' benefits incurred	85	76
Ceded contract holders' benefits incurred	(15)	(13)
Insurance losses and contract holders' benefits	$ 70	$ 63

Income Taxes - Differences Betw

Income Taxes - Differences Between Statutory Income Tax Rate and Effective Income Tax Rate (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Income Tax Disclosure [Abstract]
Tax at statutory rate	$ 182	$ (11)
Increase (decrease) resulting from:
Tax-exempt income from municipal bonds	(5)	(5)
Dividend received exclusion	(4)	(3)
Other	(1)	0
Total provision (benefit) for income taxes	$ 172	$ (19)
Tax at statutory rate	21.00%	21.00%
Increase (decrease) resulting from:
Tax-exempt income from municipal bonds	(0.60%)	10.00%
Dividend received exclusion	(0.50%)	6.00%
Other	(0.10%)	1.00%
Provision for income taxes	19.80%	38.00%

Income Taxes (Narrative) (Detai

Income Taxes (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Feb. 28, 2019	Dec. 31, 2018
Income Tax Contingency [Line Items]
Tax at statutory rate, percentage	21.00%	21.00%
Unrecognized Tax Benefits	$ 34			$ 34
MSP Underwriting Limited
Income Tax Contingency [Line Items]
Net deferred tax assets			$ 59
Valuation allowance			$ 55
Operating Loss Carryforwards	$ 192

Net Income Per Common Share - C

Net Income Per Common Share - Calculations for Basic and Diluted Earnings Per Share (Detail) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Numerator:
Net income (loss)—basic and diluted	$ 695	$ (31)
Denominator:
Basic weighted-average common shares outstanding (in shares)	163	164
Diluted weighted-average shares	164.6	164
Earnings per share:
Basic (in USD per share)	$ 4.27	$ (0.19)
Diluted (in USD per share)	$ 4.22	$ (0.19)
Number of anti-dilutive stock-based awards (in shares)	0.7	2.8
Stock Options
Denominator:
Effect of stock-based awards (in shares)	0.9	0
Nonvested shares
Denominator:
Effect of stock-based awards (in shares)	0.7	0

Employee Retirement Benefits -

Employee Retirement Benefits - Components of Net Periodic Costs for Qualified and Supplemental Pension Plans (Detail) - Qualified Pension Plans [Member] - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 2	$ 3
Interest cost	3	3
Expected return on plan assets	(5)	(5)
Amortization of actuarial loss and prior service cost	0	0
Other	1	0
Total non-service benefit	(1)	(2)
Net periodic benefit cost	$ 1	$ 1

Employee Retirement Benefits _2

Employee Retirement Benefits - Defined Contribution Plan (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Defined Benefit Plan Disclosure [Line Items]
Matching contributions to 401(k) and Top Hat plans	$ 5,000,000	$ 6,000,000
Qualified Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Pension contributions	$ 0

Segment Information (Detail)

Segment Information (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Segment Reporting Information [Line Items]
Other revenues	$ 2	$ 1
Total revenues	2,159	1,224
Investment gains and losses, net	663	(191)
ERROR in label resolution.	867	(50)
Earned premiums	1,333	1,260
Investment income, net of expenses	157	150
ERROR in label resolution.	23,352		$ 21,935
Fee revenues	4	4
Consolidated Property and Casualty Insurance Entity
Segment Reporting Information [Line Items]
ERROR in label resolution.	3,308		3,285
Life Insurance Segment
Segment Reporting Information [Line Items]
ERROR in label resolution.	1,472		1,424
Investments Segment
Segment Reporting Information [Line Items]
ERROR in label resolution.	17,738		16,741
Corporate, Non-Segment [Member]
Segment Reporting Information [Line Items]
Other revenues	2	1
Total revenues	52	30
ERROR in label resolution.	(11)	(11)
ERROR in label resolution.	834		$ 485
Corporate, Non-Segment [Member] | Reinsurance assumed and other non segment [Member]
Segment Reporting Information [Line Items]
Earned premiums	50	29
Operating Segments | Commercial Lines
Segment Reporting Information [Line Items]
Total revenues	811	792
ERROR in label resolution.	76	15
Earned premiums	810	790
Fee revenues	1	2
Operating Segments | Personal Lines
Segment Reporting Information [Line Items]
Total revenues	345	326
ERROR in label resolution.	(4)	(9)
Earned premiums	344	325
Fee revenues	1	1
Operating Segments | Excess and Surplus Lines Insurance
Segment Reporting Information [Line Items]
Total revenues	64	56
ERROR in label resolution.	11	18
Earned premiums	63	56
Fee revenues	1	0
Operating Segments | Life Insurance Segment
Segment Reporting Information [Line Items]
Total revenues	67	61
ERROR in label resolution.	(1)	2
Earned premiums	66	60
Fee revenues	1	1
Operating Segments | Investments Segment
Segment Reporting Information [Line Items]
Total revenues	820	(41)
Investment gains and losses, net	663	(191)
ERROR in label resolution.	796	(65)
Investment income, net of expenses	157	150
Commercial Casualty | Operating Segments | Commercial Lines
Segment Reporting Information [Line Items]
Earned premiums	268	265
Commercial Property | Operating Segments | Commercial Lines
Segment Reporting Information [Line Items]
Earned premiums	234	228
Commercial Auto | Operating Segments | Commercial Lines
Segment Reporting Information [Line Items]
Earned premiums	170	161
Workers' Compensation | Operating Segments | Commercial Lines
Segment Reporting Information [Line Items]
Earned premiums	77	80
Other Commercial Lines | Operating Segments | Commercial Lines
Segment Reporting Information [Line Items]
Earned premiums	61	56
Personal Auto | Operating Segments | Personal Lines
Segment Reporting Information [Line Items]
Earned premiums	155	151
Home Owner Segment | Operating Segments | Personal Lines
Segment Reporting Information [Line Items]
Earned premiums	147	136
Other Personal Lines | Operating Segments | Personal Lines
Segment Reporting Information [Line Items]
Earned premiums	$ 42	$ 38

Segment Information - Narrative

Segment Information - Narrative (Details)	3 Months Ended
	Mar. 31, 2019segmentindustry
Segment Reporting [Abstract]
Number of Industries Operating In | industry	2
Number of Reportable Segments | segment	5

Acquisition - Narrative (Detail

Acquisition - Narrative (Details) - MSP Underwriting Limited £ in Millions, $ in Millions	Feb. 28, 2019USD ($)	Feb. 28, 2019GBP (£)
Business Acquisition [Line Items]
Aggregate consideration paid	$ 64	£ 48
Amount originally estimated to be paid		£ 102
Broker Relationships And Internally Developed Technology | Minimum [Member]
Business Acquisition [Line Items]
Useful life	5 years	5 years
Broker Relationships And Internally Developed Technology | Maximum
Business Acquisition [Line Items]
Useful life	15 years	15 years

Acquisition - Schedule of Asset

Acquisition - Schedule of Assets and Liabilities Acquired (Details) - MSP Underwriting Limited $ in Millions	Feb. 28, 2019USD ($)
Assets
Investments and other invested assets	$ 198
Cash and cash equivalents	64
Premiums receivable	45
Reinsurance recoverable	42
Other assets	23
Total assets acquired	372
Liabilities
Loss and loss expense reserves	277
Unearned premiums	88
Other liabilities	24
Total liabilities assumed	389
Fair value of identifiable intangible assets:
Indefinite lived intangible assets	31
Total fair value of identifiable intangible assets	50
Total purchase price paid	64
Total assets acquired (including fair value of identifiable intangible assets)	422
Total liabilities assumed	389
Fair value of net assets acquired prior to allocation of goodwill	33
Excess of purchase price paid over fair value of net assets acquired assigned to goodwill	31
Syndicate broker relationships
Fair value of identifiable intangible assets:
Definite lived intangible assets	12
Value of business acquired (VOBA)
Fair value of identifiable intangible assets:
Definite lived intangible assets	4
Internally developed technology
Fair value of identifiable intangible assets:
Definite lived intangible assets	$ 3