Cincinnati Financial (CINF) 10-Q 27 Oct 15 2015 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2015	Oct. 23, 2015
Document Documentand Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2015
Document Fiscal Year Focus	2,015
Document Fiscal Period Focus	Q3
Trading Symbol	CINF
Entity Registrant Name	CINCINNATI FINANCIAL CORP
Entity Central Index Key	20,286
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		163,851,889

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Millions	Sep. 30, 2015	Dec. 31, 2014
Investments
Fixed maturities, at fair value (amortized cost: 2015—$9,320; 2014—$8,871)	$ 9,756	$ 9,460
Equity securities, at fair value (cost: 2015—$2,970; 2014—$2,728)	4,526	4,858
Short-term investments, at fair value (amortized cost: 2015—$75; 2014—$0)	75	0
Other invested assets	69	68
Total investments	14,426	14,386
Cash and cash equivalents	419	591
Investment income receivable	119	123
Finance receivable	65	75
Premiums receivable	1,494	1,405
Reinsurance recoverable	552	545
Prepaid reinsurance premiums	29	29
Deferred policy acquisition costs	609	578
Land, building and equipment, net, for company use (accumulated depreciation: 2015—$452; 2014—$446)	188	194
Other assets	77	75
Separate accounts	773	752
Total assets	18,751	18,753
Insurance reserves
Loss and loss expense reserves	4,700	4,485
Life policy and investment contract reserves	2,564	2,497
Unearned premiums	2,215	2,082
Other liabilities	692	648
Deferred income tax	596	840
Note payable	35	49
Long-term debt and capital lease obligations	826	827
Separate accounts	773	752
Total liabilities	12,401	12,180
Commitments and contingent liabilities (Note 12)	0	0
Shareholders' Equity
Common stock, par value—$2 per share; (authorized: 2015 and 2014—500 million shares; issued: 2015 and 2014—198.3 million shares)	397	397
Paid-in capital	1,223	1,214
Retained earnings	4,756	4,505
Accumulated other comprehensive income	1,280	1,744
Treasury stock at cost (2015— 34.5 million shares and 2014—34.6 million shares)	(1,306)	(1,287)
Total shareholders' equity	6,350	6,573
Total liabilities and shareholders' equity	$ 18,751	$ 18,753

Condensed Consolidated Balance3

Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) shares in Millions, $ in Millions	Sep. 30, 2015	Dec. 31, 2014
Statement of Financial Position [Abstract]
Fixed maturities, amortized cost	$ 9,320	$ 8,871
Equity securities, cost	2,970	2,728
Short-term investments, amortized cost	75	0
Land, building and equipment, accumulated depreciation	$ 452	$ 446
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	34.5	34.6

Condensed Consolidated Statemen

Condensed Consolidated Statements of Income - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Revenues [Abstract]
Earned premiums	$ 1,127	$ 1,071	$ 3,332	$ 3,157
Investment income, net of expenses	143	138	422	409
Realized investment gains, net	3	65	110	101
Fee revenues	4	3	10	9
Other revenues	1	3	5	7
Total revenues	1,278	1,280	3,879	3,683
Benefits and Expenses
Insurance losses and contract holders' benefits	670	686	2,131	2,181
Underwriting, acquisition and insurance expenses	348	319	1,033	967
Interest expense	14	13	40	40
Other operating expenses	3	3	10	10
Total benefits and expenses	1,035	1,021	3,214	3,198
Income Before Income Taxes	243	259	665	485
Provision for Income Taxes
Current	64	68	180	106
Deferred	5	8	7	21
Total provision for income taxes	69	76	187	127
Net Income	$ 174	$ 183	$ 478	$ 358
Per Common Share
Net income-basic (in USD per share)	$ 1.06	$ 1.12	$ 2.91	$ 2.19
Net income-diluted (in USD per share)	$ 1.05	$ 1.11	$ 2.89	$ 2.17

Condensed Consolidated Stateme5

Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Net Income	$ 174	$ 183	$ 478	$ 358
Change in unrealized gains on investments, net of tax of $(127), $(42), $(254) and $81, respectively	(238)	(78)	(473)	151
Amortization of pension actuarial loss and prior service cost, net of tax of $0, $0, $1 and $0, respectively	1	1	3	0
Change in life deferred acquisition costs, life policy reserves and other, net of tax of $1, $2, $2 and $2, respectively	3	3	6	3
Other comprehensive (loss) income, net of tax	(234)	(74)	(464)	154
Comprehensive (Loss) Income	$ (60)	$ 109	$ 14	$ 512

Condensed Consolidated Stateme6

Condensed Consolidated Statements of Comprehensive Income (Parenthetical) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Statement of Comprehensive Income [Abstract]
Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, Tax	$ (127)	$ (42)	$ (254)	$ 81
Other Comprehensive Income Loss, Pension And Other Postretirement Benefit Plans, Net Actuarial Loss And Prior Service Cost Arising During Period, Tax	0	0	1	0
Other Comprehensive Income, Change in Life Deferred Acquisition Costs, Life Policy Reserves and Other, Tax	$ 1	$ 2	$ 2	$ 2

Condensed Consolidated Stateme7

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
Balance (in shares) at Dec. 31, 2013		163.1
Balance at Dec. 31, 2013	$ 6,070	$ 397	$ 1,191	$ 4,268	$ 1,504	$ (1,290)
Net Income	358			358
Other comprehensive income, net	154				154
Dividends declared	(217)			(217)
Stock-based awards exercised and vested		$ 0
Treasury Stock, Shares, Acquired		(0.5)
Purchases	(21)					(21)
Stock Issued During Period, Shares, Other		0.8
Stockholders' Equity, Other	32		14			18
Balance (in shares) at Sep. 30, 2014		163.4
Balance at Sep. 30, 2014	$ 6,376	$ 397	1,205	4,409	1,658	(1,293)
Balance (in shares) at Dec. 31, 2014	198.3	163.7
Balance at Dec. 31, 2014	$ 6,573	$ 397	1,214	4,505	1,744	(1,287)
Net Income	478			478
Other comprehensive income, net	(464)				(464)
Dividends declared	(227)			(227)
Stock-based awards exercised and vested		$ 0
Treasury Stock, Shares, Acquired		(0.8)
Purchases	(41)					(41)
Stock Issued During Period, Shares, Other		0.9
Stockholders' Equity, Other	$ 31		9			22
Balance (in shares) at Sep. 30, 2015	198.3	163.8
Balance at Sep. 30, 2015	$ 6,350	$ 397	$ 1,223	$ 4,756	$ 1,280	$ (1,306)

Condensed Consolidated Stateme8

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Cash Flows From Operating Activities
Net Income	$ 478	$ 358
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	39	38
Realized investment gains, net	(110)	(101)
Stock-based compensation	16	15
Interest credited to contract holders'	32	35
Deferred income tax expense	7	21
Changes in:
Investment income receivable	4	2
Premiums and reinsurance receivable	(96)	(105)
Deferred policy acquisition costs	(20)	(32)
Other assets	0	0
Loss and loss expense reserves	215	124
Life policy reserves	70	104
Unearned premiums	133	152
Other liabilities	(11)	(30)
Current income tax receivable/payable	(2)	52
Net cash provided by operating activities	755	633
Cash Flows From Investing Activities
Sale of fixed maturities	25	26
Call or maturity of fixed maturities	961	675
Sale of equity securities	241	225
Purchase of fixed maturities	(1,397)	(974)
Purchase of equity securities	(379)	(294)
Purchase of short-term investments	(75)	0
Investment in finance receivables	(10)	(13)
Collection of finance receivables	22	23
Investment in buildings and equipment, net	(7)	(6)
Change in other invested assets, net	(1)	7
Net cash used in investing activities	(620)	(331)
Cash Flows From Financing Activities
Payment of cash dividends to shareholders	(218)	(208)
Purchase of treasury shares	(41)	(21)
Payments of note payable	(14)	(55)
Proceeds from stock options exercised	14	14
Contract holders' funds deposited	62	66
Contract holders' funds withdrawn	(101)	(108)
Excess tax benefits on stock-based compensation	4	2
Other	(13)	(13)
Net cash used in financing activities	(307)	(323)
Net change in cash and cash equivalents	(172)	(21)
Cash and cash equivalents at beginning of year	591	433
Cash and cash equivalents at end of period	419	412
Supplemental Disclosures of Cash Flow Information:
Interest paid	26	27
Income taxes paid	179	52
Noncash Activities:
Conversion of securities	0	7
Equipment acquired under capital lease obligations	16	10
Cashless exercise of stock options	$ 11	$ 11

Accounting Policies

Accounting Policies	9 Months Ended
	Sep. 30, 2015
Accounting Policies [Abstract]
Accounting Policies	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). 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. Our December 31, 2014 , condensed consolidated balance sheet amounts are derived from the audited financial statements but do not include all disclosures required by GAAP. Our September 30, 2015 , condensed consolidated financial statements are unaudited. Certain financial information that is included in annual financial statements prepared in accordance with GAAP is not required for interim reporting and has been condensed or omitted. 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 2014 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. Pending Accounting Updates ASU 2014-09 Revenue from Contracts with Customers In May 2014, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) 2014-09, Revenue from Contracts with Customers . ASU 2014-09 requires an entity to recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods and services. Insurance contracts do not fall within the scope of this ASU. The effective date of ASU 2014-09 is for annual reporting periods beginning after December 15, 2017. In July 2015, the FASB decided to defer by one year the effective date of this ASU. The ASU has not yet been adopted and will not have a material impact on our company’s financial position, cash flows or results of operations. ASU 2014-12, Compensation-Stock Compensation: Accounting for Share-Based Payments When the Terms of an Award Provide That a Performance Target Could Be Achieved after the Requisite Service Period In June 2014, the FASB issued ASU 2014-12, Compensation-Stock Compensation: Accounting for Share-Based Payments When the Terms of an Award Provide That a Performance Target Could Be Achieved after the Requisite Service Period. ASU 2014-12 requires that performance targets that affect vesting and that could be achieved after the requisite service period be treated as performance conditions. The effective date of ASU 2014-12 is for interim and annual reporting periods beginning after December 15, 2015. The ASU has not yet been adopted and will not have a material impact on our company’s financial position, cash flows or results of operations. ASU 2015-02, Consolidation-Amendments to the Consolidation Analysis In February 2015, the FASB issued ASU 2015-02, Consolidation-Amendments to the Consolidation Analysis. ASU 2015-02 makes amendments to the current consolidation guidance, focusing mainly on the investment management industry; however, entities across all industries may be impacted. The effective date of ASU 2015-02 is for interim and annual reporting periods beginning after December 15, 2015. The ASU has not yet been adopted and will not have a material impact on our company’s financial position, cash flows or results of operations. ASU 2015-03, Interest-Imputation of Interest In April 2015, the FASB issued ASU 2015-03, Interest-Imputation of Interest. ASU 2015-03 reduces the complexity of disclosing debt issuance costs and debt discount and premium on the balance sheet by requiring that debt issuance costs related to a recognized debt liability be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability, consistent with debt discounts. The effective date of ASU 2015-03 is for interim and annual reporting periods beginning after December 15, 2015. The ASU has not yet been adopted and will not have a material impact on our company’s financial position, cash flows or results of operations. ASU 2015-09, Financial Services-Insurance: Disclosures about Short-Duration Contracts In May 2015, the FASB issued ASU 2015-09, Financial Services-Insurance: Disclosures About Short-Duration Contracts. ASU 2015-09 requires entities to provide additional disclosures about the liability for unpaid claims and claim adjustment expenses to increase the transparency of significant estimates. ASU 2015-09 also requires entities to disclose information about significant changes in methodologies and assumptions used to calculate the liability for unpaid claims and claim adjustment expenses, including reasons for the change and the effects on the financial statements. ASU 2015-09 also requires entities to disclose a rollforward of the liability of unpaid claims and claim adjustment expense for annual and interim reporting periods. The effective date of ASU 2015-09 is for annual reporting periods beginning after December 15, 2015, and interim reporting periods within annual period beginning after December 15, 2016. The ASU has not yet been adopted and will not have a material impact on our company’s financial position, cash flows or results of operations, but the ASU will require additional disclosures to our annual and interim reporting periods. ASU 2015-15, Interest-Imputation of Interest: Presentation and Subsequent Measurement of Debt Issuance Costs Associated with Line-of-Credit Arrangements. In August 2015, the FASB issued ASU 2015-15, Interest-Imputation of Interest: Presentation and Subsequent Measurement of Debt Issuance Costs Associated with Line-of-Credit Arrangements. ASU 2015-15 allows entities to defer and present debt issuance costs as an asset and subsequently amortizing the deferred debt issuance costs ratably over the term of the line-of-credit arrangement, regardless of whether there are any outstanding borrowings on the line-of-credit arrangement. The effective date of ASU 2015-15 is for interim and annual reporting periods beginning after December 15, 2015. The ASU has not yet been adopted and will not have a material impact on our company’s financial position, cash flows or results of operations.

Investments

Investments	9 Months Ended
	Sep. 30, 2015
Investments [Abstract]
Investments	Investments The following table provides cost or amortized cost, gross unrealized gains, gross unrealized losses and fair value for our investment portfolio: (Dollars in millions) Cost or amortized cost Gross unrealized Fair value At September 30, 2015 gains losses Fixed maturity securities: Corporate $ 5,333 $ 325 $ 49 $ 5,609 States, municipalities and political subdivisions 3,401 159 3 3,557 Commercial mortgage-backed 284 9 1 292 Government-sponsored enterprises 280 — 4 276 Foreign government 10 — — 10 Convertibles and bonds with warrants attached 8 — — 8 United States government 4 — — 4 Subtotal 9,320 493 57 9,756 Equity securities: Common equities 2,784 1,585 56 4,313 Nonredeemable preferred equities 186 28 1 213 Subtotal 2,970 1,613 57 4,526 Short-term investments 75 — — 75 Total $ 12,365 $ 2,106 $ 114 $ 14,357 At December 31, 2014 Fixed maturity securities: Corporate $ 5,117 $ 420 $ 11 $ 5,526 States, municipalities and political subdivisions 3,267 178 2 3,443 Commercial mortgage-backed 250 9 — 259 Government-sponsored enterprises 213 — 5 208 Foreign government 10 — — 10 Convertibles and bonds with warrants attached 7 — — 7 United States government 7 — — 7 Subtotal 8,871 607 18 9,460 Equity securities: Common equities 2,583 2,099 3 4,679 Nonredeemable preferred equities 145 35 1 179 Subtotal 2,728 2,134 4 4,858 Total $ 11,599 $ 2,741 $ 22 $ 14,318 The net unrealized investment gains in our fixed-maturity portfolio 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 September 30, 2015 , and December 31, 2014 . At December 31, 2014 , we held no short-term investments. The seven largest unrealized investment gains in our common stock portfolio are from Exxon Mobil Corporation (NYSE:XOM), Honeywell International Incorporated (NYSE:HON), The Procter & Gamble Company (NYSE:PG), Apple Inc. (Nasdaq:AAPL), Hasbro Incorporated (Nasdaq:HAS), BlackRock Inc. (NYSE:BLK), and JPMorgan Chase & Co. (NYSE:JPM), which had a combined gross unrealized gain of $494 million . At September 30, 2015 , Apple was our largest single common stock holding with a fair value of 3.6 percent of our publicly traded common stock portfolio and 1.1 percent 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 Fair value Unrealized losses Fair value Unrealized losses Fair value Unrealized losses At September 30, 2015 Fixed maturity securities: Corporate $ 729 $ 42 $ 85 $ 7 $ 814 $ 49 States, municipalities and political subdivisions 227 3 51 — 278 3 Commercial mortgage-backed 57 1 2 — 59 1 Government-sponsored enterprises 74 1 139 3 213 4 Foreign government 10 — — — 10 — Subtotal 1,097 47 277 10 1,374 57 Equity securities: Common equities 511 56 — — 511 56 Nonredeemable preferred equities 43 1 — — 43 1 Subtotal 554 57 — — 554 57 Total $ 1,651 $ 104 $ 277 $ 10 $ 1,928 $ 114 At December 31, 2014 Fixed maturity securities: Corporate $ 261 $ 8 $ 90 $ 3 $ 351 $ 11 States, municipalities and political subdivisions 17 — 135 2 152 2 Commercial mortgage-backed 3 — 23 — 26 — Government-sponsored enterprises 11 — 181 5 192 5 Subtotal 292 8 429 10 721 18 Equity securities: Common equities 85 3 — — 85 3 Nonredeemable preferred equities 16 — 17 1 33 1 Subtotal 101 3 17 1 118 4 Total $ 393 $ 11 $ 446 $ 11 $ 839 $ 22 The following table provides investment income, realized investment gains and losses, the change in unrealized investment gains and losses, and other items: (Dollars in millions) Three months ended September 30, Nine months ended September 30, 2015 2014 2015 2014 Investment income: Interest $ 108 $ 105 $ 319 $ 312 Dividends 37 35 108 101 Other 1 — 2 2 Total 146 140 429 415 Less investment expenses 3 2 7 6 Total $ 143 $ 138 $ 422 $ 409 Realized investment gains and losses summary: Fixed maturities: Gross realized gains $ 4 $ 6 $ 14 $ 12 Gross realized losses — — — (4 ) Other-than-temporary impairments (8 ) — (11 ) — Equity securities: Gross realized gains 6 59 106 93 Gross realized losses — — (1 ) — Other-than-temporary impairments — — (1 ) (1 ) Other 1 — 3 1 Total $ 3 $ 65 $ 110 $ 101 Change in unrealized investment gains and losses: Fixed maturities $ (15 ) $ (66 ) $ (153 ) $ 115 Equity securities (350 ) (54 ) (574 ) 117 Less income taxes 127 42 254 (81 ) Total $ (238 ) $ (78 ) $ (473 ) $ 151 During the three months ended September 30, 2015 , one new equity security was other-than-temporarily impaired along with two other-than-temporarily impaired fixed-maturity securities. During the nine months ended September 30, 2015 , there were three equity securities and three 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 and nine months ended September 30, 2015 and 2014 . At September 30, 2015 , 73 fixed-maturity investments with a total unrealized loss of $10 million had been in an unrealized loss position for 12 months or more. Of that total, one fixed-maturity investment had a fair value below 70 percent of amortized cost. There were no equity investments in an unrealized loss position for 12 months or more as of September 30, 2015 . During 2014 , we other-than-temporarily impaired six fixed-maturity securities. At December 31, 2014 , 144 fixed-maturity investments with a total unrealized loss of $10 million had been in an unrealized loss position for 12 months or more. Of that total, no fixed-maturity investments had fair values below 70 percent of amortized cost. There were three equity security investments in an unrealized loss position for 12 months or more with a total unrealized loss of $1 million as of December 31, 2014 . Of that total, no equity security investments had fair values below 70 percent of cost.

Fair Value Measurements

Fair Value Measurements	9 Months Ended
	Sep. 30, 2015
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements Fair Value Hierarchy 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, 2014 , and ultimately management determines fair value. See our 2014 Annual Report on Form 10-K, Item 8, Note 3, Fair Value Measurements, Page 137, 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 September 30, 2015 , and December 31, 2014 . We do not have any material 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 September 30, 2015 Fixed maturities, available for sale: Corporate $ — $ 5,568 $ 41 $ 5,609 States, municipalities and political subdivisions — 3,557 — 3,557 Commercial mortgage-backed — 292 — 292 Government-sponsored enterprises — 276 — 276 Foreign government — 10 — 10 Convertibles and bonds with warrants attached — 8 — 8 United States government 4 — — 4 Subtotal 4 9,711 41 9,756 Common equities, available for sale 4,313 — — 4,313 Nonredeemable preferred equities, available for sale — 211 2 213 Short-term investments — 75 — 75 Separate accounts taxable fixed maturities — 754 — 754 Top Hat savings plan mutual funds and common equity (included in Other assets) 20 — — 20 Total $ 4,337 $ 10,751 $ 43 $ 15,131 At December 31, 2014 Fixed maturities, available for sale: Corporate $ — $ 5,508 $ 18 $ 5,526 States, municipalities and political subdivisions — 3,443 — 3,443 Commercial mortgage-backed — 259 — 259 Government-sponsored enterprises — 208 — 208 Foreign government — 10 — 10 Convertibles and bonds with warrants attached — 7 — 7 United States government 7 — — 7 Subtotal 7 9,435 18 9,460 Common equities, available for sale 4,679 — — 4,679 Nonredeemable preferred equities, available for sale — 177 2 179 Separate accounts taxable fixed maturities — 731 — 731 Top Hat savings plan mutual funds and common equity (included in Other assets) 18 — — 18 Total $ 4,704 $ 10,343 $ 20 $ 15,067 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 September 30, 2015 . Total Level 3 assets continue to be less than 1 percent 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. 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 September 30 : (Dollars in millions) Asset fair value measurements using significant unobservable inputs (Level 3) Corporate Commercial States, Nonredeemable preferred Total Beginning balance, June 30, 2015 $ 18 $ — $ 1 $ 2 $ 21 Total gains or losses (realized/unrealized): Included in net income — — — — — Included in other comprehensive income 1 — — — 1 Purchases 22 — — — 22 Sales — — — — — Transfers into Level 3 — — — — — Transfers out of Level 3 — — (1 ) — (1 ) Ending balance, September 30, 2015 $ 41 $ — $ — $ 2 $ 43 Beginning balance, June 30, 2014 $ 9 $ — $ — $ 2 $ 11 Total gains or losses (realized/unrealized): Included in net income — — — — — Included in other comprehensive income — — — — — Purchases — — — — — Sales — — — — — Transfers into Level 3 19 — — — 19 Transfers out of Level 3 — — — — — Ending balance, September 30, 2014 $ 28 $ — $ — $ 2 $ 30 The following table provides the change in Level 3 assets for the nine months ended September 30 : (Dollars in millions) Asset fair value measurements using significant unobservable inputs (Level 3) Corporate fixed maturities Commercial mortgage- backed fixed maturities States, municipalities and political subdivisions fixed maturities Nonredeemable preferred equities Total Beginning balance, January 1, 2015 $ 18 $ — $ — $ 2 $ 20 Total gains or losses (realized/unrealized): Included in net income — — — — — Included in other comprehensive income 1 — — — 1 Purchases 22 — — — 22 Sales — — — — — Transfers into Level 3 — — 1 — 1 Transfers out of Level 3 — — (1 ) — (1 ) Ending balance, September 30, 2015 $ 41 $ — $ — $ 2 $ 43 Beginning balance, January 1, 2014 $ 2 $ — $ — $ 2 $ 4 Total gains or losses (realized/unrealized): Included in net income — — — — — Included in other comprehensive income — — — — — Purchases — — — — — Sales — — — — — Transfers into Level 3 26 5 — — 31 Transfers out of Level 3 — (5 ) — — (5 ) Ending balance, September 30, 2014 $ 28 $ — $ — $ 2 $ 30 Additional disclosures for the Level 3 category are not material. Fair Value Disclosures for Assets and Liabilities Not Carried at Fair Value The disclosures below are presented to provide timely 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 September 30, December 31, September 30, December 31, Interest rate Year of issue 2015 2014 2015 2014 6.900 % 1998 Senior debentures, due 2028 $ 28 $ 28 $ 28 $ 28 6.920 % 2005 Senior debentures, due 2028 391 391 391 391 6.125 % 2004 Senior notes, due 2034 372 372 374 374 Total $ 791 $ 791 $ 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 September 30, 2015 Note payable $ — $ 35 $ — $ 35 6.900% senior debentures, due 2028 — 34 — 34 6.920% senior debentures, due 2028 — 498 — 498 6.125% senior notes, due 2034 — 441 — 441 Total $ — $ 1,008 $ — $ 1,008 At December 31, 2014 Note payable $ — $ 49 $ — $ 49 6.900% senior debentures, due 2028 — 34 — 34 6.920% senior debentures, due 2028 — 496 — 496 6.125% senior notes, due 2034 — 449 — 449 Total $ — $ 1,028 $ — $ 1,028 The following table shows the fair value of our life policy loans included in other invested assets: (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 September 30, 2015 Life policy loans $ — $ — $ 40 $ 40 At December 31, 2014 Life policy loans $ — $ — $ 39 $ 39 Outstanding principal and interest for these life policy loans totaled $32 million and $31 million at September 30, 2015 , and December 31, 2014 , respectively. The following table shows 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 September 30, 2015 Deferred annuities $ — $ — $ 892 $ 892 Structured settlements — 208 — 208 Total $ — $ 208 $ 892 $ 1,100 At December 31, 2014 Deferred annuities $ — $ — $ 897 $ 897 Structured settlements — 217 — 217 Total $ — $ 217 $ 897 $ 1,114 Recorded reserves for the deferred annuities were $864 million and $863 million at September 30, 2015 , and December 31, 2014 , respectively. Recorded reserves for the structured settlements were $177 million and $182 million at September 30, 2015 , and December 31, 2014 , respectively.

Property Casualty Loss and Loss

Property Casualty Loss and Loss Expenses	9 Months Ended
	Sep. 30, 2015
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 September 30, Nine months ended September 30, 2015 2014 2015 2014 Gross loss and loss expense reserves, beginning of period $ 4,647 $ 4,408 $ 4,438 $ 4,241 Less reinsurance recoverable 292 282 282 299 Net loss and loss expense reserves, beginning of period 4,355 4,126 4,156 3,942 Net incurred loss and loss expenses related to: Current accident year 661 647 2,096 2,125 Prior accident years (48 ) (25 ) (140 ) (120 ) Total incurred 613 622 1,956 2,005 Net paid loss and loss expenses related to: Current accident year 343 353 794 859 Prior accident years 261 286 954 979 Total paid 604 639 1,748 1,838 Net loss and loss expense reserves, end of period 4,364 4,109 4,364 4,109 Plus reinsurance recoverable 289 284 289 284 Gross loss and loss expense reserves, end of period $ 4,653 $ 4,393 $ 4,653 $ 4,393 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 management that 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 $47 million at September 30, 2015 , and $42 million at September 30, 2014 , for certain life and health loss and loss expense reserves. For the three months ended September 30, 2015, we experienced $48 million of favorable development on prior accident years, including $43 million of favorable development in commercial lines, $2 million of adverse development in personal lines and $7 million of favorable development in excess and surplus lines. We recognized favorable reserve development during the three months ended September 30, 2015 , of $25 million for the workers' compensation line and $16 million for the commercial casualty line due to reduced uncertainty of prior accident year loss and loss adjustment expense for these lines. Our commercial auto line developed unfavorably by $4 million for the three months ended September 30, 2015, due to higher loss cost effects in recent accident years, resulting in an increase of our reserve estimate for claims that have not yet been settled. For the nine months ended September 30, 2015 , we experienced $140 million of favorable development on prior accident years, including $120 million of favorable development in commercial lines, $1 million of adverse development in personal lines and $21 million of favorable development in excess and surplus lines. This included $12 million from favorable development of catastrophe losses for the nine months ended September 30, 2015 . We recognized favorable reserve development during the nine months ended September 30, 2015 , of $80 million for the workers' compensation line, $36 million for the commercial casualty line and $17 million for the other commercial line due to reduced uncertainty of prior accident year loss and loss adjustment expense for these lines. Our commercial auto line developed unfavorably by $27 million for the nine months ended September 30, 2015 , due to higher loss cost effects in recent accident years, resulting in an increase of our reserve estimate for claims that have not yet been settled. For the three months ended September 30, 2014 , we experienced $25 million of favorable development on prior accident years, including $24 million of favorable development in commercial lines, $5 million of adverse development in personal lines and $6 million of favorable development in excess and surplus lines. This included $5 million from favorable development of catastrophe losses for the three months ended September 30, 2014 . We recognized favorable development during the three months ended September 30, 2014 , of $15 million for workers' compensation line, $8 million for each the commercial property line and the commercial casualty line and $12 million of adverse development for the commercial auto line, due to reduced uncertainty of prior accident year loss and loss adjustment expense for these lines. For the nine months ended September 30, 2014 , we experienced $120 million of favorable development on prior accident years, including $84 million of favorable development in commercial lines, $13 million of favorable development in personal lines and $23 million of favorable development in excess and surplus lines. This included $19 million from favorable development of catastrophe losses for the nine months ended September 30, 2014 . We recognized favorable development during the nine months ended September 30, 2014 , of $45 million for the workers' compensation line, $33 million for the commercial property line, $25 million for the commercial casualty line and $24 million of adverse development in the commercial auto line, due to reduced uncertainty of prior accident year loss and loss adjustment expense for these lines.

Life Policy and Investment Cont

Life Policy and Investment Contract Reserves	9 Months Ended
	Sep. 30, 2015
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 universal life, deferred annuity 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) September 30, December 31, 2014 Ordinary/traditional life $ 928 $ 875 Deferred annuities 864 863 Universal life 547 530 Structured settlements 177 182 Other 48 47 Total life policy and investment contract reserves $ 2,564 $ 2,497

Deferred Acquisition Costs

Deferred Acquisition Costs	9 Months Ended
	Sep. 30, 2015
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 September 30, Nine months ended September 30, 2015 2014 2015 2014 Deferred policy acquisition costs asset, beginning of period $ 600 $ 571 $ 578 $ 565 Capitalized deferred policy acquisition costs 212 208 640 630 Amortized deferred policy acquisition costs (207 ) (195 ) (620 ) (598 ) Amortized shadow deferred policy acquisition costs 4 6 11 (7 ) Deferred policy acquisition costs asset, end of period $ 609 $ 590 $ 609 $ 590 No premium deficiencies were recorded in the condensed consolidated statements of income, as the sum of the anticipated loss and loss adjustment 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	9 Months Ended
	Sep. 30, 2015
Accumulated Other Comprehensive Income [Abstract]
Comprehensive Income (Loss) Note	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 September 30, 2015 2014 Before tax Income tax Net Before tax Income tax Net Investments: AOCI, beginning of period $ 2,357 $ 815 $ 1,542 $ 2,687 $ 931 $ 1,756 OCI before realized gains recognized in net income (363 ) (126 ) (237 ) (55 ) (20 ) (35 ) Realized gains recognized in net income (2 ) (1 ) (1 ) (65 ) (22 ) (43 ) OCI (365 ) (127 ) (238 ) (120 ) (42 ) (78 ) AOCI, end of period $ 1,992 $ 688 $ 1,304 $ 2,567 $ 889 $ 1,678 Pension obligations: AOCI, beginning of period $ (33 ) $ (11 ) $ (22 ) $ (19 ) $ (6 ) $ (13 ) OCI excluding amortization recognized in net income — — — — — — Amortization recognized in net income 1 — 1 — — — OCI 1 — 1 1 — 1 AOCI, end of period $ (32 ) $ (11 ) $ (21 ) $ (18 ) $ (6 ) $ (12 ) Life deferred acquisition costs, life policy reserves and other: AOCI, beginning of period $ (8 ) $ (2 ) $ (6 ) $ (16 ) $ (5 ) $ (11 ) OCI before realized gains recognized in net income 5 1 4 5 2 3 Realized gains recognized in net income (1 ) — (1 ) — — — OCI 4 1 3 5 2 3 AOCI, end of period $ (4 ) $ (1 ) $ (3 ) $ (11 ) $ (3 ) $ (8 ) Summary of AOCI: AOCI, beginning of period $ 2,316 $ 802 $ 1,514 $ 2,652 $ 920 $ 1,732 Investments OCI (365 ) (127 ) (238 ) (120 ) (42 ) (78 ) Pension obligations OCI 1 — 1 1 — 1 Life deferred acquisition costs, life policy reserves and other OCI 4 1 3 5 2 3 Total OCI (360 ) (126 ) (234 ) (114 ) (40 ) (74 ) AOCI, end of period $ 1,956 $ 676 $ 1,280 $ 2,538 $ 880 $ 1,658 (Dollars in millions) Nine months ended September 30, 2015 2014 Before tax Income tax Net Before tax Income tax Net Investments: AOCI, beginning of period $ 2,719 $ 942 $ 1,777 $ 2,335 $ 808 $ 1,527 OCI excluding realized gains recognized in net income (620 ) (216 ) (404 ) 332 115 217 Realized gains recognized in net income (107 ) (38 ) (69 ) (100 ) (34 ) (66 ) OCI (727 ) (254 ) (473 ) 232 81 151 AOCI, end of period $ 1,992 $ 688 $ 1,304 $ 2,567 $ 889 $ 1,678 Pension obligations: AOCI, beginning of period $ (36 ) $ (12 ) $ (24 ) $ (18 ) $ (6 ) $ (12 ) OCI excluding amortization recognized in net income — — — — — — Amortization recognized in net income 4 1 3 — — — OCI 4 1 3 — — — AOCI, end of period $ (32 ) $ (11 ) $ (21 ) $ (18 ) $ (6 ) $ (12 ) Life deferred acquisition costs, life policy reserves and other: AOCI, beginning of period $ (12 ) $ (3 ) $ (9 ) $ (16 ) $ (5 ) $ (11 ) OCI excluding realized gains recognized in net income 11 3 8 6 3 3 Realized gains recognized in net income (3 ) (1 ) (2 ) (1 ) (1 ) — OCI 8 2 6 5 2 3 AOCI, end of period $ (4 ) $ (1 ) $ (3 ) $ (11 ) $ (3 ) $ (8 ) Summary of AOCI: AOCI, beginning of period $ 2,671 $ 927 $ 1,744 $ 2,301 $ 797 $ 1,504 Investments OCI (727 ) (254 ) (473 ) 232 81 151 Pension obligations OCI 4 1 3 — — — Life deferred acquisition costs, life policy reserves and other OCI 8 2 6 5 2 3 Total OCI (715 ) (251 ) (464 ) 237 83 154 AOCI, end of period $ 1,956 $ 676 $ 1,280 $ 2,538 $ 880 $ 1,658 Investments realized gains and life deferred acquisition costs, life policy reserves and other realized gains are recorded in the realized investment gains, 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	9 Months Ended
	Sep. 30, 2015
Reinsurance Disclosures [Abstract]
Reinsurance	Reinsurance Reinsurance mitigates the risk of highly uncertain exposures and reduces the maximum net loss that can arise from large risks or risks concentrated in areas of exposure. 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 main components of our assumed reinsurance include involuntary as well as voluntary from our new assumed reinsurance operation. Primary components of our property casualty ceded reinsurance program include a property per risk treaty, property excess treaty, casualty per occurrence treaty, casualty excess treaty, property catastrophe treaty and catastrophe bonds and voluntary business from our new assumed reinsurance operation. Our condensed consolidated statements of income include earned consolidated property casualty insurance premiums on assumed and ceded business: (Dollars in millions) Three months ended September 30, Nine months ended September 30, 2015 2014 2015 2014 Direct earned premiums $ 1,110 $ 1,067 $ 3,279 $ 3,134 Assumed earned premiums 3 3 8 8 Ceded earned premiums (37 ) (45 ) (111 ) (132 ) Earned premiums $ 1,076 $ 1,025 $ 3,176 $ 3,010 Our condensed consolidated statements of income include incurred consolidated property casualty insurance loss and loss expenses on assumed and ceded business: (Dollars in millions) Three months ended September 30, Nine months ended September 30, 2015 2014 2015 2014 Direct incurred loss and loss expenses $ 618 $ 633 $ 1,984 $ 2,026 Assumed incurred loss and loss expenses 2 1 2 5 Ceded incurred loss and loss expenses (7 ) (12 ) (30 ) (26 ) Incurred loss and loss expenses $ 613 $ 622 $ 1,956 $ 2,005 Our ceded incurred results generally vary with our catastrophe experience. Our life insurance company purchases reinsurance for protection of a portion of the risk that is written. Primary components of our life reinsurance program include individual mortality coverage and aggregate catastrophe and accidental death coverage in excess of certain deductibles. Our condensed consolidated statements of income include earned life insurance premiums on ceded business: (Dollars in millions) Three months ended September 30, Nine months ended September 30, 2015 2014 2015 2014 Direct earned premiums $ 67 $ 61 $ 200 $ 191 Ceded earned premiums (16 ) (15 ) (44 ) (44 ) Earned premiums $ 51 $ 46 $ 156 $ 147 Our condensed consolidated statements of income include life insurance contract holders' benefits incurred on ceded business: (Dollars in millions) Three months ended September 30, Nine months ended September 30, 2015 2014 2015 2014 Direct contract holders' benefits incurred $ 70 $ 80 $ 214 $ 228 Ceded contract holders' benefits incurred (13 ) (16 ) (39 ) (52 ) Contract holders' benefits incurred $ 57 $ 64 $ 175 $ 176 The ceded benefits incurred can vary depending on the type of life insurance policy held and the year the policy was sold.

Income Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2015
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes As of September 30, 2015 , and December 31, 2014 , we had no liability for unrecognized tax benefits. The differences between the 35 percent statutory federal income tax rate and our effective income tax rate were as follows: (Dollars in millions) Three months ended September 30, Nine months ended September 30, 2015 2014 2015 2014 Tax at statutory rate: $ 85 35.0 % $ 91 35.0 % $ 233 35.0 % $ 170 35.0 % Increase (decrease) resulting from: Tax-exempt income from municipal bonds (9 ) (3.7 ) (9 ) (3.5 ) (25 ) (3.8 ) (25 ) (5.2 ) Dividend received exclusion (8 ) (3.3 ) (7 ) (2.7 ) (23 ) (3.5 ) (21 ) (4.3 ) Other 1 0.4 1 0.5 2 0.4 3 0.7 Provision for income taxes $ 69 28.4 % $ 76 29.3 % $ 187 28.1 % $ 127 26.2 % The provision for federal income taxes is based upon filing a consolidated income tax return for the company and its subsidiaries. As of September 30, 2015, we had no operating or capital loss carry forwards.

Net Income Per Common Share

Net Income Per Common Share	9 Months Ended
	Sep. 30, 2015
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 September 30, Nine months ended September 30, 2015 2014 2015 2014 Numerator: Net income—basic and diluted $ 174 $ 183 $ 478 $ 358 Denominator: Basic weighted-average common shares outstanding 164.0 163.5 164.1 163.5 Effect of share-based awards: Stock options 1.0 0.9 0.9 0.9 Nonvested shares 0.5 0.6 0.5 0.6 Diluted weighted-average shares 165.5 165.0 165.5 165.0 Earnings per share: Basic $ 1.06 $ 1.12 $ 2.91 $ 2.19 Diluted 1.05 1.11 2.89 2.17 Number of anti-dilutive share-based awards: 0.3 0.7 0.7 0.7 The sources of dilution of our common shares are certain equity-based awards. See our 2014 Annual Report on Form 10-K, Item 8, Note 17, Share-Based Associate Compensation Plans, Page 154, for information about equity-based awards. The above table shows the number of anti-dilutive share-based awards for the three and nine months ended September 30, 2015 and 2014. We did not include these share-based awards in the computation of net income per common share (diluted) because their exercise would have anti-dilutive effects.

Employee Retirement Benefits

Employee Retirement Benefits	9 Months Ended
	Sep. 30, 2015
Compensation and Retirement Disclosure [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 September 30, Nine months ended September 30, 2015 2014 2015 2014 Service cost $ 3 $ 3 $ 9 $ 8 Interest cost 3 4 10 11 Expected return on plan assets (4 ) (5 ) (13 ) (13 ) Amortization of actuarial loss and prior service cost 1 1 4 2 Net periodic benefit cost $ 3 $ 3 $ 10 $ 8 See our 2014 Annual Report on Form 10-K, Item 8, Note 13, Employee Retirement Benefits, Page 148, for information on our retirement benefits. We made matching contributions totaling $2 million and $3 million to our 401(k) and Top Hat savings plans during the third quarter of 2015 and 2014 and contributions of $9 million during both the first nine months of 2015 and 2014, respectively. We contributed $5 million to our qualified pension plan during the first quarter of 2015. We do not anticipate further contributions to our qualified pension plan during the remainder of 2015.

Commitments and Contingent Liab

Commitments and Contingent Liabilities	9 Months Ended
	Sep. 30, 2015
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 less than $1 million .

Segment Information

Segment Information	9 Months Ended
	Sep. 30, 2015
Segment Reporting [Abstract]
Segment Information	Segment Information We operate primarily in two industries, property casualty insurance and life insurance. We regularly review 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. In addition, in the third quarter of 2015, we began including results of our new assumed reinsurance operation in Other. See our 2014 Annual Report on Form 10-K, Item 8, Note 18, Segment Information, Page 157, 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 September 30, Nine months ended September 30, 2015 2014 2015 2014 Revenues: Commercial lines insurance Commercial casualty $ 257 $ 237 $ 753 $ 695 Commercial property 205 186 604 537 Commercial auto 141 133 416 391 Workers' compensation 93 93 276 280 Other commercial 61 71 186 223 Commercial lines insurance premiums 757 720 2,235 2,126 Fee revenues 1 1 3 3 Total commercial lines insurance 758 721 2,238 2,129 Personal lines insurance Personal auto 128 121 376 354 Homeowner 117 110 345 330 Other personal 32 32 96 91 Personal lines insurance premiums 277 263 817 775 Fee revenues 1 1 2 2 Total personal lines insurance 278 264 819 777 Excess and surplus lines insurance 42 42 124 109 Fee revenues — — 1 — Total excess and surplus lines insurance 42 42 125 109 Life insurance premiums 51 46 156 147 Separate account investment management fees 2 1 4 4 Total life insurance 53 47 160 151 Investments Investment income, net of expenses 143 138 422 409 Realized investment gains, net 3 65 110 101 Total investment revenue 146 203 532 510 Other 1 3 5 7 Total revenues $ 1,278 $ 1,280 $ 3,879 $ 3,683 Income (loss) before income taxes: Insurance underwriting results Commercial lines insurance $ 121 $ 67 $ 244 $ 97 Personal lines insurance (2 ) 14 (30 ) (33 ) Excess and surplus lines insurance 14 13 29 22 Life insurance 1 (4 ) (1 ) (5 ) Investments 125 182 468 448 Other (16 ) (13 ) (45 ) (44 ) Total income before income taxes $ 243 $ 259 $ 665 $ 485 Identifiable assets: September 30, December 31, 2014 Property casualty insurance $ 2,568 $ 2,656 Life insurance 1,328 1,316 Investments 14,476 14,441 Other 379 340 Total $ 18,751 $ 18,753

Accounting Policies Pending Acc

Accounting Policies Pending Accounting Updates (Policies)	9 Months Ended
	Sep. 30, 2015
Accounting Policies [Abstract]
Revenue Recognition, Policy [Policy Text Block]	ASU 2014-09 Revenue from Contracts with Customers
Compensation Related Costs, Policy [Policy Text Block]	ASU 2014-12, Compensation-Stock Compensation: Accounting for Share-Based Payments When the Terms of an Award Provide That a Performance Target Could Be Achieved after the Requisite Service Period In June 2014, the FASB issued ASU 2014-12, Compensation-Stock Compensation: Accounting for Share-Based Payments When the Terms of an Award Provide That a Performance Target Could Be Achieved after the Requisite Service Period. ASU 2014-12 requires that performance targets that affect vesting and that could be achieved after the requisite service period be treated as performance conditions. The effective date of ASU 2014-12 is for interim and annual reporting periods beginning after December 15, 2015. The ASU has not yet been adopted and will not have a material impact on our company’s financial position, cash flows or results of operations.
Consolidation, Policy [Policy Text Block]	ASU 2015-02, Consolidation-Amendments to the Consolidation Analysis In February 2015, the FASB issued ASU 2015-02, Consolidation-Amendments to the Consolidation Analysis. ASU 2015-02 makes amendments to the current consolidation guidance, focusing mainly on the investment management industry; however, entities across all industries may be impacted. The effective date of ASU 2015-02 is for interim and annual reporting periods beginning after December 15, 2015. The ASU has not yet been adopted and will not have a material impact on our company’s financial position, cash flows or results of operations.
Interest Capitalization, Policy [Policy Text Block]	ASU 2015-15, Interest-Imputation of Interest: Presentation and Subsequent Measurement of Debt Issuance Costs Associated with Line-of-Credit Arrangements. In August 2015, the FASB issued ASU 2015-15, Interest-Imputation of Interest: Presentation and Subsequent Measurement of Debt Issuance Costs Associated with Line-of-Credit Arrangements. ASU 2015-15 allows entities to defer and present debt issuance costs as an asset and subsequently amortizing the deferred debt issuance costs ratably over the term of the line-of-credit arrangement, regardless of whether there are any outstanding borrowings on the line-of-credit arrangement. The effective date of ASU 2015-15 is for interim and annual reporting periods beginning after December 15, 2015. The ASU has not yet been adopted and will not have a material impact on our company’s financial position, cash flows or results of operations. ASU 2015-03, Interest-Imputation of Interest In April 2015, the FASB issued ASU 2015-03, Interest-Imputation of Interest. ASU 2015-03 reduces the complexity of disclosing debt issuance costs and debt discount and premium on the balance sheet by requiring that debt issuance costs related to a recognized debt liability be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability, consistent with debt discounts. The effective date of ASU 2015-03 is for interim and annual reporting periods beginning after December 15, 2015. The ASU has not yet been adopted and will not have a material impact on our company’s financial position, cash flows or results of operations.
Short-Duration Contracts, Policy [Policy Text Block]	ASU 2015-09, Financial Services-Insurance: Disclosures about Short-Duration Contracts In May 2015, the FASB issued ASU 2015-09, Financial Services-Insurance: Disclosures About Short-Duration Contracts. ASU 2015-09 requires entities to provide additional disclosures about the liability for unpaid claims and claim adjustment expenses to increase the transparency of significant estimates. ASU 2015-09 also requires entities to disclose information about significant changes in methodologies and assumptions used to calculate the liability for unpaid claims and claim adjustment expenses, including reasons for the change and the effects on the financial statements. ASU 2015-09 also requires entities to disclose a rollforward of the liability of unpaid claims and claim adjustment expense for annual and interim reporting periods. The effective date of ASU 2015-09 is for annual reporting periods beginning after December 15, 2015, and interim reporting periods within annual period beginning after December 15, 2016. The ASU has not yet been adopted and will not have a material impact on our company’s financial position, cash flows or results of operations, but the ASU will require additional disclosures to our annual and interim reporting periods.

Investments (Tables)

Investments (Tables)	9 Months Ended
	Sep. 30, 2015
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 investment portfolio: (Dollars in millions) Cost or amortized cost Gross unrealized Fair value At September 30, 2015 gains losses Fixed maturity securities: Corporate $ 5,333 $ 325 $ 49 $ 5,609 States, municipalities and political subdivisions 3,401 159 3 3,557 Commercial mortgage-backed 284 9 1 292 Government-sponsored enterprises 280 — 4 276 Foreign government 10 — — 10 Convertibles and bonds with warrants attached 8 — — 8 United States government 4 — — 4 Subtotal 9,320 493 57 9,756 Equity securities: Common equities 2,784 1,585 56 4,313 Nonredeemable preferred equities 186 28 1 213 Subtotal 2,970 1,613 57 4,526 Short-term investments 75 — — 75 Total $ 12,365 $ 2,106 $ 114 $ 14,357 At December 31, 2014 Fixed maturity securities: Corporate $ 5,117 $ 420 $ 11 $ 5,526 States, municipalities and political subdivisions 3,267 178 2 3,443 Commercial mortgage-backed 250 9 — 259 Government-sponsored enterprises 213 — 5 208 Foreign government 10 — — 10 Convertibles and bonds with warrants attached 7 — — 7 United States government 7 — — 7 Subtotal 8,871 607 18 9,460 Equity securities: Common equities 2,583 2,099 3 4,679 Nonredeemable preferred equities 145 35 1 179 Subtotal 2,728 2,134 4 4,858 Total $ 11,599 $ 2,741 $ 22 $ 14,318
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 Fair value Unrealized losses Fair value Unrealized losses Fair value Unrealized losses At September 30, 2015 Fixed maturity securities: Corporate $ 729 $ 42 $ 85 $ 7 $ 814 $ 49 States, municipalities and political subdivisions 227 3 51 — 278 3 Commercial mortgage-backed 57 1 2 — 59 1 Government-sponsored enterprises 74 1 139 3 213 4 Foreign government 10 — — — 10 — Subtotal 1,097 47 277 10 1,374 57 Equity securities: Common equities 511 56 — — 511 56 Nonredeemable preferred equities 43 1 — — 43 1 Subtotal 554 57 — — 554 57 Total $ 1,651 $ 104 $ 277 $ 10 $ 1,928 $ 114 At December 31, 2014 Fixed maturity securities: Corporate $ 261 $ 8 $ 90 $ 3 $ 351 $ 11 States, municipalities and political subdivisions 17 — 135 2 152 2 Commercial mortgage-backed 3 — 23 — 26 — Government-sponsored enterprises 11 — 181 5 192 5 Subtotal 292 8 429 10 721 18 Equity securities: Common equities 85 3 — — 85 3 Nonredeemable preferred equities 16 — 17 1 33 1 Subtotal 101 3 17 1 118 4 Total $ 393 $ 11 $ 446 $ 11 $ 839 $ 22
Investment Income, Realized Investment Gains And Losses And Change In Unrealized Investment Gains And Losses	The following table provides investment income, realized investment gains and losses, the change in unrealized investment gains and losses, and other items: (Dollars in millions) Three months ended September 30, Nine months ended September 30, 2015 2014 2015 2014 Investment income: Interest $ 108 $ 105 $ 319 $ 312 Dividends 37 35 108 101 Other 1 — 2 2 Total 146 140 429 415 Less investment expenses 3 2 7 6 Total $ 143 $ 138 $ 422 $ 409 Realized investment gains and losses summary: Fixed maturities: Gross realized gains $ 4 $ 6 $ 14 $ 12 Gross realized losses — — — (4 ) Other-than-temporary impairments (8 ) — (11 ) — Equity securities: Gross realized gains 6 59 106 93 Gross realized losses — — (1 ) — Other-than-temporary impairments — — (1 ) (1 ) Other 1 — 3 1 Total $ 3 $ 65 $ 110 $ 101 Change in unrealized investment gains and losses: Fixed maturities $ (15 ) $ (66 ) $ (153 ) $ 115 Equity securities (350 ) (54 ) (574 ) 117 Less income taxes 127 42 254 (81 ) Total $ (238 ) $ (78 ) $ (473 ) $ 151

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	9 Months Ended
	Sep. 30, 2015
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
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 September 30, 2015 , and December 31, 2014 . We do not have any material 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 September 30, 2015 Fixed maturities, available for sale: Corporate $ — $ 5,568 $ 41 $ 5,609 States, municipalities and political subdivisions — 3,557 — 3,557 Commercial mortgage-backed — 292 — 292 Government-sponsored enterprises — 276 — 276 Foreign government — 10 — 10 Convertibles and bonds with warrants attached — 8 — 8 United States government 4 — — 4 Subtotal 4 9,711 41 9,756 Common equities, available for sale 4,313 — — 4,313 Nonredeemable preferred equities, available for sale — 211 2 213 Short-term investments — 75 — 75 Separate accounts taxable fixed maturities — 754 — 754 Top Hat savings plan mutual funds and common equity (included in Other assets) 20 — — 20 Total $ 4,337 $ 10,751 $ 43 $ 15,131 At December 31, 2014 Fixed maturities, available for sale: Corporate $ — $ 5,508 $ 18 $ 5,526 States, municipalities and political subdivisions — 3,443 — 3,443 Commercial mortgage-backed — 259 — 259 Government-sponsored enterprises — 208 — 208 Foreign government — 10 — 10 Convertibles and bonds with warrants attached — 7 — 7 United States government 7 — — 7 Subtotal 7 9,435 18 9,460 Common equities, available for sale 4,679 — — 4,679 Nonredeemable preferred equities, available for sale — 177 2 179 Separate accounts taxable fixed maturities — 731 — 731 Top Hat savings plan mutual funds and common equity (included in Other assets) 18 — — 18 Total $ 4,704 $ 10,343 $ 20 $ 15,067
Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3)	(Dollars in millions) Asset fair value measurements using significant unobservable inputs (Level 3) Corporate Commercial States, Nonredeemable preferred Total Beginning balance, June 30, 2015 $ 18 $ — $ 1 $ 2 $ 21 Total gains or losses (realized/unrealized): Included in net income — — — — — Included in other comprehensive income 1 — — — 1 Purchases 22 — — — 22 Sales — — — — — Transfers into Level 3 — — — — — Transfers out of Level 3 — — (1 ) — (1 ) Ending balance, September 30, 2015 $ 41 $ — $ — $ 2 $ 43 Beginning balance, June 30, 2014 $ 9 $ — $ — $ 2 $ 11 Total gains or losses (realized/unrealized): Included in net income — — — — — Included in other comprehensive income — — — — — Purchases — — — — — Sales — — — — — Transfers into Level 3 19 — — — 19 Transfers out of Level 3 — — — — — Ending balance, September 30, 2014 $ 28 $ — $ — $ 2 $ 30 The following table provides the change in Level 3 assets for the nine months ended September 30 : (Dollars in millions) Asset fair value measurements using significant unobservable inputs (Level 3) Corporate fixed maturities Commercial mortgage- backed fixed maturities States, municipalities and political subdivisions fixed maturities Nonredeemable preferred equities Total Beginning balance, January 1, 2015 $ 18 $ — $ — $ 2 $ 20 Total gains or losses (realized/unrealized): Included in net income — — — — — Included in other comprehensive income 1 — — — 1 Purchases 22 — — — 22 Sales — — — — — Transfers into Level 3 — — 1 — 1 Transfers out of Level 3 — — (1 ) — (1 ) Ending balance, September 30, 2015 $ 41 $ — $ — $ 2 $ 43 Beginning balance, January 1, 2014 $ 2 $ — $ — $ 2 $ 4 Total gains or losses (realized/unrealized): Included in net income — — — — — Included in other comprehensive income — — — — — Purchases — — — — — Sales — — — — — Transfers into Level 3 26 5 — — 31 Transfers out of Level 3 — (5 ) — — (5 ) Ending balance, September 30, 2014 $ 28 $ — $ — $ 2 $ 30
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 September 30, December 31, September 30, December 31, Interest rate Year of issue 2015 2014 2015 2014 6.900 % 1998 Senior debentures, due 2028 $ 28 $ 28 $ 28 $ 28 6.920 % 2005 Senior debentures, due 2028 391 391 391 391 6.125 % 2004 Senior notes, due 2034 372 372 374 374 Total $ 791 $ 791 $ 793 $ 793
Fair Value of Life Policy Loans	The following table shows the fair value of our life policy loans included in other invested assets: (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 September 30, 2015 Life policy loans $ — $ — $ 40 $ 40 At December 31, 2014 Life policy loans $ — $ — $ 39 $ 39
Debt
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
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 September 30, 2015 Note payable $ — $ 35 $ — $ 35 6.900% senior debentures, due 2028 — 34 — 34 6.920% senior debentures, due 2028 — 498 — 498 6.125% senior notes, due 2034 — 441 — 441 Total $ — $ 1,008 $ — $ 1,008 At December 31, 2014 Note payable $ — $ 49 $ — $ 49 6.900% senior debentures, due 2028 — 34 — 34 6.920% senior debentures, due 2028 — 496 — 496 6.125% senior notes, due 2034 — 449 — 449 Total $ — $ 1,028 $ — $ 1,028
Deferred Annuities, Structured Settlements, And Other
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fair Values of Deferred Annuities, Structured Settlements and Other Items	The following table shows 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 September 30, 2015 Deferred annuities $ — $ — $ 892 $ 892 Structured settlements — 208 — 208 Total $ — $ 208 $ 892 $ 1,100 At December 31, 2014 Deferred annuities $ — $ — $ 897 $ 897 Structured settlements — 217 — 217 Total $ — $ 217 $ 897 $ 1,114

Property Casualty Loss and Lo25

Property Casualty Loss and Loss Expenses (Tables)	9 Months Ended
	Sep. 30, 2015
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 September 30, Nine months ended September 30, 2015 2014 2015 2014 Gross loss and loss expense reserves, beginning of period $ 4,647 $ 4,408 $ 4,438 $ 4,241 Less reinsurance recoverable 292 282 282 299 Net loss and loss expense reserves, beginning of period 4,355 4,126 4,156 3,942 Net incurred loss and loss expenses related to: Current accident year 661 647 2,096 2,125 Prior accident years (48 ) (25 ) (140 ) (120 ) Total incurred 613 622 1,956 2,005 Net paid loss and loss expenses related to: Current accident year 343 353 794 859 Prior accident years 261 286 954 979 Total paid 604 639 1,748 1,838 Net loss and loss expense reserves, end of period 4,364 4,109 4,364 4,109 Plus reinsurance recoverable 289 284 289 284 Gross loss and loss expense reserves, end of period $ 4,653 $ 4,393 $ 4,653 $ 4,393

Life Policy and Investment Co26

Life Policy and Investment Contract Reserves (Tables)	9 Months Ended
	Sep. 30, 2015
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) September 30, December 31, 2014 Ordinary/traditional life $ 928 $ 875 Deferred annuities 864 863 Universal life 547 530 Structured settlements 177 182 Other 48 47 Total life policy and investment contract reserves $ 2,564 $ 2,497

Deferred Acquisition Costs (Ta

Deferred Acquisition Costs (Tables)	9 Months Ended
	Sep. 30, 2015
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 September 30, Nine months ended September 30, 2015 2014 2015 2014 Deferred policy acquisition costs asset, beginning of period $ 600 $ 571 $ 578 $ 565 Capitalized deferred policy acquisition costs 212 208 640 630 Amortized deferred policy acquisition costs (207 ) (195 ) (620 ) (598 ) Amortized shadow deferred policy acquisition costs 4 6 11 (7 ) Deferred policy acquisition costs asset, end of period $ 609 $ 590 $ 609 $ 590

Accumulated Other Comprehensi28

Accumulated Other Comprehensive Income (Tables)	9 Months Ended
	Sep. 30, 2015
Accumulated Other Comprehensive Income [Abstract]
Schedule of Accumulated Other Comprehensive Income (Loss)	(Dollars in millions) Three months ended September 30, 2015 2014 Before tax Income tax Net Before tax Income tax Net Investments: AOCI, beginning of period $ 2,357 $ 815 $ 1,542 $ 2,687 $ 931 $ 1,756 OCI before realized gains recognized in net income (363 ) (126 ) (237 ) (55 ) (20 ) (35 ) Realized gains recognized in net income (2 ) (1 ) (1 ) (65 ) (22 ) (43 ) OCI (365 ) (127 ) (238 ) (120 ) (42 ) (78 ) AOCI, end of period $ 1,992 $ 688 $ 1,304 $ 2,567 $ 889 $ 1,678 Pension obligations: AOCI, beginning of period $ (33 ) $ (11 ) $ (22 ) $ (19 ) $ (6 ) $ (13 ) OCI excluding amortization recognized in net income — — — — — — Amortization recognized in net income 1 — 1 — — — OCI 1 — 1 1 — 1 AOCI, end of period $ (32 ) $ (11 ) $ (21 ) $ (18 ) $ (6 ) $ (12 ) Life deferred acquisition costs, life policy reserves and other: AOCI, beginning of period $ (8 ) $ (2 ) $ (6 ) $ (16 ) $ (5 ) $ (11 ) OCI before realized gains recognized in net income 5 1 4 5 2 3 Realized gains recognized in net income (1 ) — (1 ) — — — OCI 4 1 3 5 2 3 AOCI, end of period $ (4 ) $ (1 ) $ (3 ) $ (11 ) $ (3 ) $ (8 ) Summary of AOCI: AOCI, beginning of period $ 2,316 $ 802 $ 1,514 $ 2,652 $ 920 $ 1,732 Investments OCI (365 ) (127 ) (238 ) (120 ) (42 ) (78 ) Pension obligations OCI 1 — 1 1 — 1 Life deferred acquisition costs, life policy reserves and other OCI 4 1 3 5 2 3 Total OCI (360 ) (126 ) (234 ) (114 ) (40 ) (74 ) AOCI, end of period $ 1,956 $ 676 $ 1,280 $ 2,538 $ 880 $ 1,658 (Dollars in millions) Nine months ended September 30, 2015 2014 Before tax Income tax Net Before tax Income tax Net Investments: AOCI, beginning of period $ 2,719 $ 942 $ 1,777 $ 2,335 $ 808 $ 1,527 OCI excluding realized gains recognized in net income (620 ) (216 ) (404 ) 332 115 217 Realized gains recognized in net income (107 ) (38 ) (69 ) (100 ) (34 ) (66 ) OCI (727 ) (254 ) (473 ) 232 81 151 AOCI, end of period $ 1,992 $ 688 $ 1,304 $ 2,567 $ 889 $ 1,678 Pension obligations: AOCI, beginning of period $ (36 ) $ (12 ) $ (24 ) $ (18 ) $ (6 ) $ (12 ) OCI excluding amortization recognized in net income — — — — — — Amortization recognized in net income 4 1 3 — — — OCI 4 1 3 — — — AOCI, end of period $ (32 ) $ (11 ) $ (21 ) $ (18 ) $ (6 ) $ (12 ) Life deferred acquisition costs, life policy reserves and other: AOCI, beginning of period $ (12 ) $ (3 ) $ (9 ) $ (16 ) $ (5 ) $ (11 ) OCI excluding realized gains recognized in net income 11 3 8 6 3 3 Realized gains recognized in net income (3 ) (1 ) (2 ) (1 ) (1 ) — OCI 8 2 6 5 2 3 AOCI, end of period $ (4 ) $ (1 ) $ (3 ) $ (11 ) $ (3 ) $ (8 ) Summary of AOCI: AOCI, beginning of period $ 2,671 $ 927 $ 1,744 $ 2,301 $ 797 $ 1,504 Investments OCI (727 ) (254 ) (473 ) 232 81 151 Pension obligations OCI 4 1 3 — — — Life deferred acquisition costs, life policy reserves and other OCI 8 2 6 5 2 3 Total OCI (715 ) (251 ) (464 ) 237 83 154 AOCI, end of period $ 1,956 $ 676 $ 1,280 $ 2,538 $ 880 $ 1,658

Reinsurance (Tables)

Reinsurance (Tables)	9 Months Ended
	Sep. 30, 2015
Reinsurance Disclosures [Abstract]
Earned Consolidated Property Casualty Insurance Premiums On Assumed And Ceded Business	Our condensed consolidated statements of income include earned consolidated property casualty insurance premiums on assumed and ceded business: (Dollars in millions) Three months ended September 30, Nine months ended September 30, 2015 2014 2015 2014 Direct earned premiums $ 1,110 $ 1,067 $ 3,279 $ 3,134 Assumed earned premiums 3 3 8 8 Ceded earned premiums (37 ) (45 ) (111 ) (132 ) Earned premiums $ 1,076 $ 1,025 $ 3,176 $ 3,010
Incurred Consolidated Property Casualty Insurance Loss And Loss Expenses On Assumed And Ceded Business	Our condensed consolidated statements of income include incurred consolidated property casualty insurance loss and loss expenses on assumed and ceded business: (Dollars in millions) Three months ended September 30, Nine months ended September 30, 2015 2014 2015 2014 Direct incurred loss and loss expenses $ 618 $ 633 $ 1,984 $ 2,026 Assumed incurred loss and loss expenses 2 1 2 5 Ceded incurred loss and loss expenses (7 ) (12 ) (30 ) (26 ) Incurred loss and loss expenses $ 613 $ 622 $ 1,956 $ 2,005
Earned Life Insurance Premiums On Ceded Business	Our condensed consolidated statements of income include earned life insurance premiums on ceded business: (Dollars in millions) Three months ended September 30, Nine months ended September 30, 2015 2014 2015 2014 Direct earned premiums $ 67 $ 61 $ 200 $ 191 Ceded earned premiums (16 ) (15 ) (44 ) (44 ) Earned premiums $ 51 $ 46 $ 156 $ 147
Life Insurance Contract Holders' Benefits Incurred On Ceded Business	Our condensed consolidated statements of income include life insurance contract holders' benefits incurred on ceded business: (Dollars in millions) Three months ended September 30, Nine months ended September 30, 2015 2014 2015 2014 Direct contract holders' benefits incurred $ 70 $ 80 $ 214 $ 228 Ceded contract holders' benefits incurred (13 ) (16 ) (39 ) (52 ) Contract holders' benefits incurred $ 57 $ 64 $ 175 $ 176

Income Taxes (Tables)

Income Taxes (Tables)	9 Months Ended
	Sep. 30, 2015
Income Tax Disclosure [Abstract]
Differences Between The 35 Percent Statutory Income Tax Rate And Effective Income Tax Rate	The differences between the 35 percent statutory federal income tax rate and our effective income tax rate were as follows: (Dollars in millions) Three months ended September 30, Nine months ended September 30, 2015 2014 2015 2014 Tax at statutory rate: $ 85 35.0 % $ 91 35.0 % $ 233 35.0 % $ 170 35.0 % Increase (decrease) resulting from: Tax-exempt income from municipal bonds (9 ) (3.7 ) (9 ) (3.5 ) (25 ) (3.8 ) (25 ) (5.2 ) Dividend received exclusion (8 ) (3.3 ) (7 ) (2.7 ) (23 ) (3.5 ) (21 ) (4.3 ) Other 1 0.4 1 0.5 2 0.4 3 0.7 Provision for income taxes $ 69 28.4 % $ 76 29.3 % $ 187 28.1 % $ 127 26.2 %

Net Income Per Common Share (Ta

Net Income Per Common Share (Tables)	9 Months Ended
	Sep. 30, 2015
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 September 30, Nine months ended September 30, 2015 2014 2015 2014 Numerator: Net income—basic and diluted $ 174 $ 183 $ 478 $ 358 Denominator: Basic weighted-average common shares outstanding 164.0 163.5 164.1 163.5 Effect of share-based awards: Stock options 1.0 0.9 0.9 0.9 Nonvested shares 0.5 0.6 0.5 0.6 Diluted weighted-average shares 165.5 165.0 165.5 165.0 Earnings per share: Basic $ 1.06 $ 1.12 $ 2.91 $ 2.19 Diluted 1.05 1.11 2.89 2.17 Number of anti-dilutive share-based awards: 0.3 0.7 0.7 0.7

Employee Retirement Benefits (T

Employee Retirement Benefits (Tables)	9 Months Ended
	Sep. 30, 2015
Compensation and Retirement Disclosure [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 September 30, Nine months ended September 30, 2015 2014 2015 2014 Service cost $ 3 $ 3 $ 9 $ 8 Interest cost 3 4 10 11 Expected return on plan assets (4 ) (5 ) (13 ) (13 ) Amortization of actuarial loss and prior service cost 1 1 4 2 Net periodic benefit cost $ 3 $ 3 $ 10 $ 8

Segment Information (Tables)

Segment Information (Tables)	9 Months Ended
	Sep. 30, 2015
Segment Reporting [Abstract]
Segment Information	Segment information is summarized in the following table: (Dollars in millions) Three months ended September 30, Nine months ended September 30, 2015 2014 2015 2014 Revenues: Commercial lines insurance Commercial casualty $ 257 $ 237 $ 753 $ 695 Commercial property 205 186 604 537 Commercial auto 141 133 416 391 Workers' compensation 93 93 276 280 Other commercial 61 71 186 223 Commercial lines insurance premiums 757 720 2,235 2,126 Fee revenues 1 1 3 3 Total commercial lines insurance 758 721 2,238 2,129 Personal lines insurance Personal auto 128 121 376 354 Homeowner 117 110 345 330 Other personal 32 32 96 91 Personal lines insurance premiums 277 263 817 775 Fee revenues 1 1 2 2 Total personal lines insurance 278 264 819 777 Excess and surplus lines insurance 42 42 124 109 Fee revenues — — 1 — Total excess and surplus lines insurance 42 42 125 109 Life insurance premiums 51 46 156 147 Separate account investment management fees 2 1 4 4 Total life insurance 53 47 160 151 Investments Investment income, net of expenses 143 138 422 409 Realized investment gains, net 3 65 110 101 Total investment revenue 146 203 532 510 Other 1 3 5 7 Total revenues $ 1,278 $ 1,280 $ 3,879 $ 3,683 Income (loss) before income taxes: Insurance underwriting results Commercial lines insurance $ 121 $ 67 $ 244 $ 97 Personal lines insurance (2 ) 14 (30 ) (33 ) Excess and surplus lines insurance 14 13 29 22 Life insurance 1 (4 ) (1 ) (5 ) Investments 125 182 468 448 Other (16 ) (13 ) (45 ) (44 ) Total income before income taxes $ 243 $ 259 $ 665 $ 485 Identifiable assets: September 30, December 31, 2014 Property casualty insurance $ 2,568 $ 2,656 Life insurance 1,328 1,316 Investments 14,476 14,441 Other 379 340 Total $ 18,751 $ 18,753

Investments - Analysis of Cost

Investments - Analysis of Cost or Amortized Cost, Gross Unrealized Gains and Losses and Fair Value for Investments (Detail) - USD ($) $ in Millions	Sep. 30, 2015	Dec. 31, 2014
Debt Securities
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	$ 9,320	$ 8,871
Gross Unrealized Gains	493	607
Gross Unrealized Losses	57	18
Fair Value	9,756	9,460
Debt Securities | Corporate
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	5,333	5,117
Gross Unrealized Gains	325	420
Gross Unrealized Losses	49	11
Fair Value	5,609	5,526
Debt Securities | States, municipalities and political subdivisions
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	3,401	3,267
Gross Unrealized Gains	159	178
Gross Unrealized Losses	3	2
Fair Value	3,557	3,443
Debt Securities | Commercial mortgage-backed
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	284	250
Gross Unrealized Gains	9	9
Gross Unrealized Losses	1	0
Fair Value	292	259
Debt Securities | Government-sponsored enterprises
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	280	213
Gross Unrealized Gains	0	0
Gross Unrealized Losses	4	5
Fair Value	276	208
Debt Securities | Foreign government
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	10	10
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	10	10
Debt Securities | Convertibles and bonds with warrants attached
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	8	7
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	8	7
Debt Securities | United States government
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	4	7
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	4	7
Equity Securities
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	2,970	2,728
Gross Unrealized Gains	1,613	2,134
Gross Unrealized Losses	57	4
Fair Value	4,526	4,858
Equity Securities | Common equities
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	2,784	2,583
Gross Unrealized Gains	1,585	2,099
Gross Unrealized Losses	56	3
Fair Value	4,313	4,679
Equity Securities | Nonredeemable preferred equities
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	186	145
Gross Unrealized Gains	28	35
Gross Unrealized Losses	1	1
Fair Value	213	179
Fixed Maturities And Equity Securities
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	12,365	11,599
Gross Unrealized Gains	2,106	2,741
Gross Unrealized Losses	114	22
Fair Value	$ 14,357	$ 14,318

Investments - Fair Values and U

Investments - Fair Values and Unrealized Losses by Investment Category and by Duration of Securities' Continuous Unrealized Loss Position (Detail) - USD ($) $ in Millions	Sep. 30, 2015	Dec. 31, 2014
Investments, Unrealized Loss Position [Line Items]
Less than 12 months Fair Value	$ 1,651	$ 393
Less than 12 months Unrealized Losses	104	11
12 months or more Fair Value	277	446
12 months or more Unrealized Losses	10	11
Total Fair Value	1,928	839
Total Unrealized Losses	114	22
Fixed Maturities
Investments, Unrealized Loss Position [Line Items]
Less than 12 months Fair Value	1,097	292
Less than 12 months Unrealized Losses	47	8
12 months or more Fair Value	277	429
12 months or more Unrealized Losses	10	10
Total Fair Value	1,374	721
Total Unrealized Losses	57	18
Fixed Maturities | Corporate
Investments, Unrealized Loss Position [Line Items]
Less than 12 months Fair Value	729	261
Less than 12 months Unrealized Losses	42	8
12 months or more Fair Value	85	90
12 months or more Unrealized Losses	7	3
Total Fair Value	814	351
Total Unrealized Losses	49	11
Fixed Maturities | States, municipalities and political subdivisions
Investments, Unrealized Loss Position [Line Items]
Less than 12 months Fair Value	227	17
Less than 12 months Unrealized Losses	3	0
12 months or more Fair Value	51	135
12 months or more Unrealized Losses	0	2
Total Fair Value	278	152
Total Unrealized Losses	3	2
Fixed Maturities | Commercial mortgage-backed
Investments, Unrealized Loss Position [Line Items]
Less than 12 months Fair Value	57	3
Less than 12 months Unrealized Losses	1	0
12 months or more Fair Value	2	23
12 months or more Unrealized Losses	0	0
Total Fair Value	59	26
Total Unrealized Losses	1	0
Fixed Maturities | Government-sponsored enterprises
Investments, Unrealized Loss Position [Line Items]
Less than 12 months Fair Value	74	11
Less than 12 months Unrealized Losses	1	0
12 months or more Fair Value	139	181
12 months or more Unrealized Losses	3	5
Total Fair Value	213	192
Total Unrealized Losses	4	5
Fixed Maturities | Foreign government
Investments, Unrealized Loss Position [Line Items]
Less than 12 months Fair Value	10
Less than 12 months Unrealized Losses	0
12 months or more Fair Value	0
12 months or more Unrealized Losses	0
Total Fair Value	10
Total Unrealized Losses	0
Equity Securities
Investments, Unrealized Loss Position [Line Items]
Less than 12 months Fair Value	554	101
Less than 12 months Unrealized Losses	57	3
12 months or more Fair Value	0	17
12 months or more Unrealized Losses	0	1
Total Fair Value	554	118
Total Unrealized Losses	57	4
Equity Securities | Common equities
Investments, Unrealized Loss Position [Line Items]
Less than 12 months Fair Value	511	85
Less than 12 months Unrealized Losses	56	3
12 months or more Fair Value	0	0
12 months or more Unrealized Losses	0	0
Total Fair Value	511	85
Total Unrealized Losses	56	3
Equity Securities | Nonredeemable preferred equities
Investments, Unrealized Loss Position [Line Items]
Less than 12 months Fair Value	43	16
Less than 12 months Unrealized Losses	1	0
12 months or more Fair Value	0	17
12 months or more Unrealized Losses	0	1
Total Fair Value	43	33
Total Unrealized Losses	$ 1	$ 1

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		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Investment income summary:
Interest	$ 108	$ 105	$ 319	$ 312
Dividends	37	35	108	101
Other	1	0	2	2
Total	146	140	429	415
Less investment expenses	3	2	7	6
Total	143	138	422	409
Realized investment gains and losses summary:
Realized investment gains, net	3	65	110	101
Change in unrealized gains and losses summary:
Fixed maturities	(238)	(78)	(473)	151
Less income taxes	127	42	(254)	81
Fixed Maturities
Realized investment gains and losses summary:
Gross realized gains	4	6	14	12
Gross realized losses	0	0	0	(4)
Other-than-temporary impairments	(8)	0	(11)	0
Change in unrealized gains and losses summary:
Fixed maturities	(15)	(66)	(153)	115
Equity Securities
Realized investment gains and losses summary:
Gross realized gains	6	59	106	93
Gross realized losses	0	0	(1)	0
Other-than-temporary impairments	0	0	(1)	(1)
Other	1	0	3	1
Change in unrealized gains and losses summary:
Fixed maturities	$ (350)	$ (54)	$ (574)	$ 117

Investments - Additional Inform

Investments - Additional Information (Detail) $ in Millions	3 Months Ended	9 Months Ended	12 Months Ended
	Sep. 30, 2015USD ($)security	Sep. 30, 2015USD ($)security	Dec. 31, 2014USD ($)security
Gain (Loss) on Investments [Line Items]
Short-term investments, at fair value (amortized cost: 2015—$75; 2014—$0)	$ 75	$ 75	$ 0
Largest equity holdings to total equity portfolio	3.60%	3.60%
Largest equity holdings to total portfolio	1.10%	1.10%
Unrealized losses 12 months or more (equity investment less than $500,000)	$ 10	$ 10	$ 11
Number Of Securities Other Than Temporary Impairment Losses			6
Fixed maturity investments, Percentage of amortized costs		70.00%	70.00%
Fixed Maturities
Gain (Loss) on Investments [Line Items]
Unrealized investment gains due to a net gain position	$ 493	$ 493	$ 607
Number Of Securities Other Than Temporary Impairment Losses1 | security	2	3
Number Of Securities Continuous Unrealized Loss Position More Than Twelve Months | security	73	73	144
Unrealized losses 12 months or more (equity investment less than $500,000)	$ 10	$ 10	$ 10
Equity Securities
Gain (Loss) on Investments [Line Items]
Unrealized investment gains due to a net gain position	$ 1,613	$ 1,613	$ 2,134
Number Of Securities Other Than Temporary Impairment Losses1 | security	1	3
Number Of Securities Continuous Unrealized Loss Position More Than Twelve Months	0	0	3
Unrealized losses 12 months or more (equity investment less than $500,000)	$ 0	$ 0	$ 1
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Loss, Accumulated in Investments			$ 1
Procter And Gamble Company, Exxon Mobile Corporation And Chevron Corporation [Member]
Gain (Loss) on Investments [Line Items]
Unrealized investment gains due to a net gain position	$ 494	$ 494
Common equities
Gain (Loss) on Investments [Line Items]
Number of securities	7	7

Fair Value Measurements - Fair

Fair Value Measurements - Fair Value Hierarchy for Assets Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Millions	Sep. 30, 2015	Dec. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value	$ 9,756	$ 9,460
Equity securities, at fair value	4,526	4,858
Short-term investments, at fair value (amortized cost: 2015—$75; 2014—$0)	75	0
Separate accounts	773	752
Fair value of asset	15,131	15,067
Short-term investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments, at fair value (amortized cost: 2015—$75; 2014—$0)	75
Top Hat savings plan mutual funds and common equity (included in Other assets)
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)	20	18
Debt Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value	9,756	9,460
Debt Securities | Corporate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value	5,609	5,526
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	3,557	3,443
Debt Securities | Commercial mortgage-backed
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value	292	259
Debt Securities | Government-sponsored enterprises
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value	276	208
Debt Securities | Foreign government
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value	10	10
Debt Securities | Convertibles and bonds with warrants attached
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value	8	7
Debt Securities | United States government
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value	4	7
Equity Securities | Common equities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities, at fair value	4,313	4,679
Equity Securities | Nonredeemable preferred equities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities, at fair value	213	179
Taxable Fixed Maturities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Separate accounts	754	731
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 asset	4,337	4,704
Quoted prices in active markets for identical assets (Level 1) | Short-term investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments, at fair value (amortized cost: 2015—$75; 2014—$0)	0
Quoted prices in active markets for identical assets (Level 1) | Top Hat savings plan mutual funds and common equity (included in Other assets)
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)	20	18
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	4	7
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 | 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 | 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 | 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) | Debt Securities | Convertibles and bonds with warrants attached
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	4	7
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	4,313	4,679
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]
Fair value of asset	10,751	10,343
Significant other observable inputs (Level 2) | Short-term investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments, at fair value (amortized cost: 2015—$75; 2014—$0)	75
Significant other observable inputs (Level 2) | Top Hat savings plan mutual funds and common equity (included in Other assets)
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
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	9,711	9,435
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	5,568	5,508
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	3,557	3,443
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	292	259
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	276	208
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	10	10
Significant other observable inputs (Level 2) | Debt Securities | Convertibles and bonds with warrants attached
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value	8	7
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) | 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	211	177
Significant other observable inputs (Level 2) | Taxable Fixed Maturities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Separate accounts	754	731
Significant unobservable inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of asset	43	20
Significant unobservable inputs (Level 3) | Short-term investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments, at fair value (amortized cost: 2015—$75; 2014—$0)	0
Significant unobservable inputs (Level 3) | Top Hat savings plan mutual funds and common equity (included in Other assets)
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
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	41	18
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	41	18
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	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 | 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 | 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) | Debt Securities | Convertibles and bonds with warrants attached
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) | 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	2	2
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		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	$ 21	$ 11	$ 20	$ 4
Total gains or losses (realized/unrealized):
Included in net income	0	0	0	0
Included in other comprehensive income	1	0	1	0
Purchases	22	0	22	0
Sales	0	0	0	0
Transfers into Level 3	0	19	1	31
Transfers out of Level 3	(1)	0	(1)	(5)
Ending balance	43	30	43	30
Corporate Fixed Maturities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	18	9	18	2
Total gains or losses (realized/unrealized):
Included in net income	0	0	0	0
Included in other comprehensive income	1	0	1	0
Purchases	22	0	22	0
Sales	0	0	0	0
Transfers into Level 3	0	19	0	26
Transfers out of Level 3	0	0	0	0
Ending balance	41	28	41	28
Commercial mortgage-backed
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	0	0	0	0
Total gains or losses (realized/unrealized):
Included in net income	0	0	0	0
Included in other comprehensive income	0	0	0	0
Purchases	0	0	0	0
Sales	0	0	0	0
Transfers into Level 3	0	0	0	5
Transfers out of Level 3	0	0	0	(5)
Ending balance	0	0	0	0
States, Municipalities And Political Subdivisions Fixed Maturities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	1	0	0	0
Total gains or losses (realized/unrealized):
Included in net income	0	0	0	0
Included in other comprehensive income	0	0	0	0
Purchases	0	0	0	0
Sales	0	0	0	0
Transfers into Level 3	0	0	1	0
Transfers out of Level 3	(1)	0	(1)	0
Ending balance	0	0	0	0
Preferred Equities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	2	2	2	2
Total gains or losses (realized/unrealized):
Included in net income	0	0	0	0
Included in other comprehensive income	0	0	0	0
Purchases	0	0	0	0
Sales	0	0	0	0
Transfers into Level 3	0	0	0	0
Transfers out of Level 3	0	0	0	0
Ending balance	$ 2	$ 2	$ 2	$ 2

Fair Value Measurements - Summa

Fair Value Measurements - Summary of Book Value and Principal Amounts of Long-Term Debt (Detail) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
	Sep. 30, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Book value	$ 791	$ 791
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	1,998	1,998
Book value	$ 28	$ 28
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	2,005	2,005
Book value	$ 391	$ 391
Principal amount of debt	$ 391	$ 391
Senior Notes 6.152% Due 2034
Debt Instrument [Line Items]
Interest rate	6.125%	6.125%
Debt issuance year	2,004	2,004
Book value	$ 372	$ 372
Principal amount of debt	$ 374	$ 374

Fair Value Measurements - Fai41

Fair Value Measurements - Fair Values of Note Payable and Long-Term Debt (Detail) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
	Sep. 30, 2015	Dec. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of note payable	$ 35	$ 49
Total	1,008	1,028
Finance receivable	$ 65	$ 75
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	2,028	2,028
Fair value of senior debt	$ 34	$ 34
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	2,028	2,028
Fair value of senior debt	$ 498	$ 496
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	2,034	2,034
Fair value of senior debt	$ 441	$ 449
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	35	49
Total	1,008	1,028
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	34	34
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	498	496
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	441	449
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
Deferred Annuities And Structured Settlements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liability for Future Policy Benefits, Individual and Group Annuities and Supplementary Contracts	864	863
Policy Loans [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Finance receivable	$ 32	$ 31

Fair Value Measurements - Fai42

Fair Value Measurements - Fair Value of Life Policy Loans (Detail) - USD ($) $ in Millions	Sep. 30, 2015	Dec. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Finance receivable	$ 65	$ 75
Fair value of life policy loans	40	39
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
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
Significant unobservable inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of life policy loans	40	39
Policy Loans [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Finance receivable	$ 32	$ 31

Fair Value Measurements - Fai43

Fair Value Measurements - Fair Values of Deferred Annuities, Structured Settlements and Other Items (Detail) - USD ($) $ in Millions	Sep. 30, 2015	Dec. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value of life insurance liabilities	$ 1,100	$ 1,114
Deferred Annuities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value of life insurance liabilities	892	897
Structured Settlements
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value of life insurance liabilities	208	217
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 insurance liabilities	0	0
Quoted prices in active markets for identical assets (Level 1) | Deferred Annuities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value of life insurance liabilities	0	0
Quoted prices in active markets for identical assets (Level 1) | Structured Settlements
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value of life insurance liabilities	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 insurance liabilities	208	217
Significant other observable inputs (Level 2) | Deferred Annuities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value of life insurance liabilities	0	0
Significant other observable inputs (Level 2) | Structured Settlements
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value of life insurance liabilities	208	217
Significant unobservable inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value of life insurance liabilities	892	897
Significant unobservable inputs (Level 3) | Deferred Annuities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value of life insurance liabilities	892	897
Significant unobservable inputs (Level 3) | Structured Settlements
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value of life insurance liabilities	$ 0	$ 0

Fair Value Measurements - Addit

Fair Value Measurements - Additional Information (Detail) - USD ($) $ in Millions	Sep. 30, 2015	Dec. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Finance receivable	$ 65	$ 75
Loss and loss expense reserves	4,700	4,485
Life Policy Loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Finance receivable	32	31
Deferred Annuities And Structured Settlements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liability for Future Policy Benefits, Individual and Group Annuities and Supplementary Contracts	864	863
Loss and loss expense reserves	$ 177	$ 182
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 Lo45

Property Casualty Loss and Loss Expenses - Consolidated Property Casualty Loss and Loss Expense Reserves (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Summary of Consolidated Property Casualty Loss and Loss Expense Reserves [Roll Forward]
Gross loss and loss expense reserves, beginning of period	$ 4,647	$ 4,408	$ 4,438	$ 4,241
Less reinsurance recoverable	292	282	282	299
Net loss and loss expense reserves, beginning of period	4,355	4,126	4,156	3,942
Current accident year	661	647	2,096	2,125
Prior accident years	(48)	(25)	(140)	(120)
Total incurred	613	622	1,956	2,005
Current accident year	343	353	794	859
Prior accident years	261	286	954	979
Total paid	604	639	1,748	1,838
Net loss and loss expense reserves, end of period	4,364	4,109	4,364	4,109
Plus reinsurance recoverable	289	284	289	284
Gross loss and loss expense reserves, end of period	$ 4,653	$ 4,393	$ 4,653	$ 4,393

Property Casualty Loss and Lo46

Property Casualty Loss and Loss Expenses - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Jun. 30, 2015	Dec. 31, 2014	Jun. 30, 2014	Dec. 31, 2013
Supplemental Information for Property, Casualty Insurance Underwriters [Line Items]
Reserve for loss and loss expenses	$ 4,653	$ 4,393	$ 4,653	$ 4,393	$ 4,647	$ 4,438	$ 4,408	$ 4,241
Prior accident years	(48)	(25)	(140)	(120)
Life and Health Loss Reserves
Supplemental Information for Property, Casualty Insurance Underwriters [Line Items]
Reserve for loss and loss expenses	47	42	47	42
Commercial Lines
Supplemental Information for Property, Casualty Insurance Underwriters [Line Items]
Prior accident years	(43)	(24)	(120)	(84)
Commercial Lines | Workers' Compensation
Supplemental Information for Property, Casualty Insurance Underwriters [Line Items]
Prior accident years	(25)	(15)	(80)	(45)
Commercial Lines | Commercial Casualty Segment [Member]
Supplemental Information for Property, Casualty Insurance Underwriters [Line Items]
Prior accident years	(16)	(8)	(36)	(25)
Commercial Lines | Other Commercial Lines [Member]
Supplemental Information for Property, Casualty Insurance Underwriters [Line Items]
Prior accident years			(17)
Commercial Lines | Commercial Auto
Supplemental Information for Property, Casualty Insurance Underwriters [Line Items]
Prior accident years	4	12	27	24
Commercial Lines | Commercial Property Segment [Member]
Supplemental Information for Property, Casualty Insurance Underwriters [Line Items]
Prior accident years		(8)		(33)
Personal Lines
Supplemental Information for Property, Casualty Insurance Underwriters [Line Items]
Prior accident years	2	5	1	(13)
Excess and Surplus Lines Insurance
Supplemental Information for Property, Casualty Insurance Underwriters [Line Items]
Prior accident years	$ (7)	(6)	(21)	(23)
Consolidated Property and Casualty Insurance Entity | Catastrophe Development
Supplemental Information for Property, Casualty Insurance Underwriters [Line Items]
Prior accident years		$ (5)	$ (12)	$ (19)

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	Sep. 30, 2015	Dec. 31, 2014
Liability for Future Policy Benefit, by Product Segment [Line Items]
Life policy and investment contract reserves	$ 2,564	$ 2,497
Ordinary/Traditional Life
Liability for Future Policy Benefit, by Product Segment [Line Items]
Life policy and investment contract reserves	928	875
Deferred Annuities
Liability for Future Policy Benefit, by Product Segment [Line Items]
Life policy and investment contract reserves	864	863
Universal Life
Liability for Future Policy Benefit, by Product Segment [Line Items]
Life policy and investment contract reserves	547	530
Structured Settlements
Liability for Future Policy Benefit, by Product Segment [Line Items]
Life policy and investment contract reserves	177	182
Other
Liability for Future Policy Benefit, by Product Segment [Line Items]
Life policy and investment contract reserves	$ 48	$ 47

Deferred Acquisition Costs - De

Deferred Acquisition Costs - Deferred Policy Acquisition Costs and Asset Reconciliation (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Movement Analysis of Deferred Policy Acquisition Costs [Roll Forward]
Deferred policy acquisition costs asset, beginning of period	$ 600	$ 571	$ 578	$ 565
Capitalized deferred policy acquisition costs	212	208	640	630
Amortized deferred policy acquisition costs	(207)	(195)	(620)	(598)
Amortized shadow deferred policy acquisition costs	4	6	11	(7)
Deferred policy acquisition costs asset, end of period	$ 609	$ 590	$ 609	$ 590

Accumulated Other Comprehensi49

Accumulated Other Comprehensive Income (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Jun. 30, 2015	Dec. 31, 2014	Jun. 30, 2014	Dec. 31, 2013
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Accumulated other comprehensive income, net of tax, beginning of period	$ 1,280		$ 1,280			$ 1,744
Accumulated other comprehensive income, net of tax, end of period	1,280		1,280
Accumulated Net Unrealized Investment Gain (Loss)
Accumulated Other Comprehensive Income Loss Before Tax [Abstract]
Accumulated other comprehensive income, before tax, beginning of period	2,357	$ 2,687	2,719	$ 2,335
Other comprehensive income before reclassification, before tax	(363)	(55)	(620)	332
Reclassification adjustment, before tax	(2)	(65)	(107)	(100)
Effect on other comprehensive income, before tax	(365)	(120)	(727)	232
Accumulated other comprehensive income, before tax, end of period	1,992	2,567	1,992	2,567
Accumulated Other Comprehensive Income (Loss), Tax [Abstract]
Accumulated other comprehensive income, tax, beginning of period	815	931	942	808
Other comprehensive income before reclassification, tax	(126)	(20)	(216)	115
Reclassification adjustment, tax	(1)	(22)	(38)	(34)
Effect on other comprehensive income, tax	(127)	(42)	(254)	81
Accumulated other comprehensive income, tax, end of period	688	889	688	889
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Accumulated other comprehensive income, net of tax, beginning of period	1,304	1,678	1,304	1,678	$ 1,542	1,777	$ 1,756	$ 1,527
Other comprehensive income before reclassification, net of tax	(237)	(35)	(404)	217
Reclassification adjustment, net of tax	(1)	(43)	(69)	(66)
Effect on other comprehensive income, net of tax	(238)	(78)	(473)	151
Accumulated other comprehensive income, net of tax, end of period	1,304	1,678	1,304	1,678
Accumulated Defined Benefit Plans Adjustment
Accumulated Other Comprehensive Income Loss Before Tax [Abstract]
Accumulated other comprehensive income, before tax, beginning of period	(33)	(19)	(36)	(18)
Other comprehensive income before reclassification, before tax	0	0	0	0
Reclassification adjustment, before tax	1	0	4	0
Effect on other comprehensive income, before tax	1	1	4	0
Accumulated other comprehensive income, before tax, end of period	(32)	(18)	(32)	(18)
Accumulated Other Comprehensive Income (Loss), Tax [Abstract]
Accumulated other comprehensive income, tax, beginning of period	(11)	(6)	(12)	(6)
Other comprehensive income before reclassification, tax	0	0	0	0
Reclassification adjustment, tax	0	0	1	0
Effect on other comprehensive income, tax	0	0	1	0
Accumulated other comprehensive income, tax, end of period	(11)	(6)	(11)	(6)
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Accumulated other comprehensive income, net of tax, beginning of period	(21)	(12)	(21)	(12)	(22)	(24)	(13)	(12)
Other comprehensive income before reclassification, net of tax	0	0	0	0
Reclassification adjustment, net of tax	1	0	3	0
Effect on other comprehensive income, net of tax	1	1	3	0
Accumulated other comprehensive income, net of tax, end of period	(21)	(12)	(21)	(12)
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	(8)	(16)	(12)	(16)
Other comprehensive income before reclassification, before tax	5	5	11	6
Reclassification adjustment, before tax	(1)	0	(3)	(1)
Effect on other comprehensive income, before tax	4	5	8	5
Accumulated other comprehensive income, before tax, end of period	(4)	(11)	(4)	(11)
Accumulated Other Comprehensive Income (Loss), Tax [Abstract]
Accumulated other comprehensive income, tax, beginning of period	(2)	(5)	(3)	(5)
Other comprehensive income before reclassification, tax	1	2	3	3
Reclassification adjustment, tax	0	0	(1)	(1)
Effect on other comprehensive income, tax	1	2	2	2
Accumulated other comprehensive income, tax, end of period	(1)	(3)	(1)	(3)
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Accumulated other comprehensive income, net of tax, beginning of period	(3)	(8)	(3)	(8)	(6)	(9)	(11)	(11)
Other comprehensive income before reclassification, net of tax	4	3	8	3
Reclassification adjustment, net of tax	(1)	0	(2)	0
Effect on other comprehensive income, net of tax	3	3	6	3
Accumulated other comprehensive income, net of tax, end of period	(3)	(8)	(3)	(8)
Accumulated Other Comprehensive Income (Loss)
Accumulated Other Comprehensive Income Loss Before Tax [Abstract]
Accumulated other comprehensive income, before tax, beginning of period	2,316	2,652	2,671	2,301
Change in unrealized gains, net, on investments available for sale, before tax	(365)	(120)	(727)	232
Change in pension obligations, before tax	1	1	4	0
Change in life deferred acquisition costs, life policy reserves and other, before tax	4	5	8	5
Effect on other comprehensive income, before tax	(360)	(114)	(715)	237
Accumulated other comprehensive income, before tax, end of period	1,956	2,538	1,956	2,538
Accumulated Other Comprehensive Income (Loss), Tax [Abstract]
Accumulated other comprehensive income, tax, beginning of period	802	920	927	797
Change in unrealized gains, net, on investments available for sale, tax	(127)	(42)	(254)	81
Change in pension obligations, tax	0	0	1	0
Change in life deferred acquisition costs, life policy reserves and other, tax	1	2	2	2
Effect on other comprehensive income, tax	(126)	(40)	(251)	83
Accumulated other comprehensive income, tax, end of period	676	880	676	880
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Accumulated other comprehensive income, net of tax, beginning of period	1,280	1,658	1,280	1,658	$ 1,514	$ 1,744	$ 1,732	$ 1,504
Change in unrealized gains, net, on investments available for sale, net of tax	(238)	(78)	(473)	151
Change in pension obligations, net of tax	1	1	3	0
Change in life deferred acquisition costs, life policy reserves and other, net of tax	3	3	6	3
Effect on other comprehensive income, net of tax	(234)	(74)	(464)	154
Accumulated other comprehensive income, net of tax, end of period	$ 1,280	$ 1,658	$ 1,280	$ 1,658

Reinsurance - Earned Consolidat

Reinsurance - Earned Consolidated Property Casualty Insurance Premiums on Assumed and Ceded Business (Detail) - Consolidated Property and Casualty Insurance Entity - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Direct earned premiums	$ 1,110	$ 1,067	$ 3,279	$ 3,134
Assumed earned premiums	3	3	8	8
Ceded earned premiums	(37)	(45)	(111)	(132)
Earned premiums	$ 1,076	$ 1,025	$ 3,176	$ 3,010

Reinsurance - Incurred Consolid

Reinsurance - Incurred Consolidated Property Casualty Insurance Loss and Loss Expenses on Assumed and Ceded Business (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Incurred loss and loss expenses	$ 670	$ 686	$ 2,131	$ 2,181
Consolidated Property and Casualty Insurance Entity
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Direct incurred loss and loss expenses	618	633	1,984	2,026
Assumed incurred loss and loss expenses	2	1	2	5
Ceded incurred loss and loss expenses	(7)	(12)	(30)	(26)
Incurred loss and loss expenses	$ 613	$ 622	$ 1,956	$ 2,005

Reinsurance - Earned Life Insur

Reinsurance - Earned Life Insurance Premiums on Ceded Business (Detail) - Life Insurance Segment - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Direct earned premiums	$ 67	$ 61	$ 200	$ 191
Ceded earned premiums	(16)	(15)	(44)	(44)
Earned premiums	$ 51	$ 46	$ 156	$ 147

Reinsurance - Life Insurance Co

Reinsurance - Life Insurance Contract Holders' Benefits Incurred on Ceded Business (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Insurance losses and contract holders' benefits	$ 670	$ 686	$ 2,131	$ 2,181
Life Insurance Segment
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Direct contract holders' benefits incurred	70	80	214	228
Ceded contract holders' benefits incurred	(13)	(16)	(39)	(52)
Insurance losses and contract holders' benefits	$ 57	$ 64	$ 175	$ 176

Income Taxes - Differences Betw

Income Taxes - Differences Between 35 Percent Statutory Income Tax Rate and Effective Income Tax Rate (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Income Tax Disclosure [Abstract]
Tax at statutory rate	$ 85	$ 91	$ 233	$ 170
Increase (decrease) resulting from:
Tax-exempt income from municipal bonds	(9)	(9)	(25)	(25)
Dividend received exclusion	(8)	(7)	(23)	(21)
Other	1	1	2	3
Total provision for income taxes	$ 69	$ 76	$ 187	$ 127
Tax at statutory rate	35.00%	35.00%	35.00%	35.00%
Increase (decrease) resulting from:
Tax-exempt income from municipal bonds	(3.70%)	(3.50%)	(3.80%)	(5.20%)
Dividend received exclusion	(3.30%)	(2.70%)	(3.50%)	(4.30%)
Other	0.40%	0.50%	0.40%	0.70%
Provision for income taxes	28.40%	29.30%	28.10%	26.20%

Income Taxes (Narrative) (Detai

Income Taxes (Narrative) (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Income Tax Disclosure [Abstract]
Tax at statutory rate, percentage	35.00%	35.00%	35.00%	35.00%

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		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Numerator:
Net income-basic and diluted	$ 174	$ 183	$ 478	$ 358
Denominator:
Basic weighted-average common shares outstanding (in shares)	164	163.5	164.1	163.5
Diluted weighted-average shares	165.5	165	165.5	165
Earnings per share:
Basic (in USD per share)	$ 1.06	$ 1.12	$ 2.91	$ 2.19
Diluted (in USD per share)	$ 1.05	$ 1.11	$ 2.89	$ 2.17
Number of anti-dilutive stock-based awards (in shares)	0.3	0.7	0.7	0.7
Stock Options
Denominator:
Effect of stock-based awards (in shares)	1	0.9	0.9	0.9
Nonvested shares
Denominator:
Effect of stock-based awards (in shares)	0.5	0.6	0.5	0.6

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		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 3	$ 3	$ 9	$ 8
Interest cost	3	4	10	11
Expected return on plan assets	(4)	(5)	(13)	(13)
Amortization of actuarial loss and prior service cost	1	1	4	2
Net periodic benefit cost	$ 3	$ 3	$ 10	$ 8

Employee Retirement Benefits 58

Employee Retirement Benefits - Defined Contribution Plan (Detail) - USD ($) $ in Millions	3 Months Ended			9 Months Ended
	Sep. 30, 2015	Mar. 31, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Defined Benefit Plan Disclosure [Line Items]
Matching contributions to 401(k) and Top Hat plans	$ 2		$ 3	$ 9	$ 9
Qualified Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected contributions by employer in the remainder of year	$ 0			$ 0
Pension contributions		$ 5

Commitments and Contingent Li59

Commitments and Contingent Liabilities (Narrative) (Details) $ in Millions	9 Months Ended
	Sep. 30, 2015USD ($)
Commitments and Contingencies Disclosure [Abstract]
Estimate for which the risk of loss is more than remote but not probable	$ 1

Segment Information (Detail)

Segment Information (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Segment Reporting Information [Line Items]
Earned premiums	$ 1,127	$ 1,071	$ 3,332	$ 3,157
Fee revenues	4	3	10	9
Investment income, net of expenses	143	138	422	409
Realized investment gains, net	3	65	110	101
Other	1	3	5	7
Total revenues	1,278	1,280	3,879	3,683
Income (loss) before income taxes	243	259	665	485
Identifiable assets	18,751		18,751		$ 18,753
Consolidated Property and Casualty Insurance Entity
Segment Reporting Information [Line Items]
Identifiable assets	2,568		2,568		2,656
Life Insurance Segment
Segment Reporting Information [Line Items]
Identifiable assets	1,328		1,328		1,316
Investments Segment
Segment Reporting Information [Line Items]
Identifiable assets	14,476		14,476		14,441
Operating Segments | Commercial Lines
Segment Reporting Information [Line Items]
Earned premiums	757	720	2,235	2,126
Fee revenues	1	1	3	3
Total revenues	758	721	2,238	2,129
Income (loss) before income taxes	121	67	244	97
Operating Segments | Personal Lines
Segment Reporting Information [Line Items]
Earned premiums	277	263	817	775
Fee revenues	1	1	2	2
Total revenues	278	264	819	777
Income (loss) before income taxes	(2)	14	(30)	(33)
Operating Segments | Excess and Surplus Lines Insurance
Segment Reporting Information [Line Items]
Earned premiums	42	42	124	109
Fee revenues	0	0	1	0
Total revenues	42	42	125	109
Income (loss) before income taxes	14	13	29	22
Operating Segments | Life Insurance Segment
Segment Reporting Information [Line Items]
Earned premiums	51	46	156	147
Fee revenues	2	1	4	4
Total revenues	53	47	160	151
Income (loss) before income taxes	1	(4)	(1)	(5)
Operating Segments | Investments Segment
Segment Reporting Information [Line Items]
Investment income, net of expenses	143	138	422	409
Realized investment gains, net	3	65	110	101
Total revenues	146	203	532	510
Income (loss) before income taxes	125	182	468	448
Corporate and Other Non-Segment
Segment Reporting Information [Line Items]
Other	1	3	5	7
Income (loss) before income taxes	(16)	(13)	(45)	(44)
Identifiable assets	379		379		$ 340
Commercial Casualty | Operating Segments | Commercial Lines
Segment Reporting Information [Line Items]
Earned premiums	257	237	753	695
Commercial Property | Operating Segments | Commercial Lines
Segment Reporting Information [Line Items]
Earned premiums	205	186	604	537
Commercial Auto | Operating Segments | Commercial Lines
Segment Reporting Information [Line Items]
Earned premiums	141	133	416	391
Workers' Compensation | Operating Segments | Commercial Lines
Segment Reporting Information [Line Items]
Earned premiums	93	93	276	280
Other Commercial Lines | Operating Segments | Commercial Lines
Segment Reporting Information [Line Items]
Earned premiums	61	71	186	223
Personal Auto | Operating Segments | Personal Lines
Segment Reporting Information [Line Items]
Earned premiums	128	121	376	354
Home Owner Segment | Operating Segments | Personal Lines
Segment Reporting Information [Line Items]
Earned premiums	117	110	345	330
Other Personal Lines | Operating Segments | Personal Lines
Segment Reporting Information [Line Items]
Earned premiums	$ 32	$ 32	$ 96	$ 91

Segment Information - Narrative

Segment Information - Narrative (Details)	9 Months Ended
	Sep. 30, 2015segmentindustry
Segment Reporting [Abstract]
Number of Industries Operating In | industry	2
Number of Reportable Segments	5