Cincinnati Financial (CINF) 10-Q 29 Jul 14 2014 Q2 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	6 Months Ended
	Jun. 30, 2014	Jul. 24, 2014
Document Documentand Entity Information [Abstract]	'	'
Document Type	'10-Q	'
Amendment Flag	'false	'
Document Period End Date	30-Jun-14	'
Document Fiscal Year Focus	'2014	'
Document Fiscal Period Focus	'Q2	'
Trading Symbol	'CINF	'
Entity Registrant Name	'CINCINNATI FINANCIAL CORP	'
Entity Central Index Key	'0000020286	'
Current Fiscal Year End Date	'--12-31	'
Entity Filer Category	'Large Accelerated Filer	'
Entity Common Stock, Shares Outstanding	'	163,651,181

Condensed_Consolidated_Balance

Condensed Consolidated Balance Sheets (USD $)	Jun. 30, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Investments	'	'
Fixed maturities, at fair value (amortized cost: 2014—$8,719; 2013—$8,638)	$9,383	$9,121
Equity securities, at fair value (cost: 2014—$2,582; 2013—$2,523)	4,605	4,375
Other invested assets	72	68
Total investments	14,060	13,564
Cash and cash equivalents	462	433
Investment income receivable	116	121
Finance receivable	80	85
Premiums receivable	1,462	1,346
Reinsurance recoverable	526	547
Prepaid reinsurance premiums	26	26
Deferred policy acquisition costs	571	565
Land, building and equipment, net, for company use (accumulated depreciation: 2014—$431; 2013—$420)	203	210
Other assets	98	73
Separate accounts	731	692
Total assets	18,335	17,662
Insurance reserves	'	'
Loss and loss expense reserves	4,444	4,311
Life policy and investment contract reserves	2,454	2,390
Unearned premiums	2,110	1,976
Other liabilities	563	611
Deferred income tax	810	673
Note payable	49	104
Long-term debt and capital lease obligations	831	835
Separate accounts	731	692
Total liabilities	11,992	11,592
Commitments and contingent liabilities (Note 12)	0	0
Shareholders' Equity	'	'
Common stock, par value—$2 per share; (authorized: 2014 and 2013—500 million shares; issued: 2014 and 2013—198 million shares)	397	397
Paid-in capital	1,198	1,191
Retained earnings	4,299	4,268
Accumulated other comprehensive income	1,732	1,504
Treasury stock at cost (2014—34 million and 2013—35 million shares)	-1,283	-1,290
Total shareholders' equity	6,343	6,070
Total liabilities and shareholders' equity	$18,335	$17,662

Condensed_Consolidated_Balance1

Condensed Consolidated Balance Sheets (Parenthetical) (USD $)	Jun. 30, 2014	Dec. 31, 2013
In Millions, except Per Share data, unless otherwise specified
Statement of Financial Position [Abstract]	'	'
Fixed maturities, amortized cost	$8,719	$8,638
Equity securities, cost	2,582	2,523
Land, building and equipment, accumulated depreciation	$431	$420
Common stock, par value	$2	$2
Common stock, authorized	500	500
Common stock, issued	198	198
Common stock, outstanding	198	198
Treasury stock, shares	34	35

Condensed_Consolidated_Stateme

Condensed Consolidated Statements of Income (USD $)	3 Months Ended		6 Months Ended
In Millions, except Per Share data, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Revenues [Abstract]	'	'	'	'
Earned premiums	$1,059	$954	$2,086	$1,885
Investment income, net of expenses	136	131	271	259
Realized investment gains, net	14	14	36	55
Fee revenues	3	3	6	4
Other revenues	2	2	4	4
Total revenues	1,214	1,104	2,403	2,207
Benefits and Expenses	'	'	'	'
Insurance losses and policyholder benefits	763	631	1,495	1,199
Underwriting, acquisition and insurance expenses	328	307	648	607
Interest expense	13	14	27	27
Other operating expenses	3	4	7	9
Total benefits and expenses	1,107	956	2,177	1,842
Income Before Income Taxes	107	148	226	365
Provision for Income Taxes	'	'	'	'
Current	18	37	38	91
Deferred	5	1	13	10
Total provision for income taxes	23	38	51	101
Net Income	$84	$110	$175	$264
Per Common Share	'	'	'	'
Net income-basic (in USD per share)	$0.51	$0.67	$1.07	$1.62
Net income-diluted (in USD per share)	$0.51	$0.66	$1.06	$1.60

Condensed_Consolidated_Stateme1

Condensed Consolidated Statements of Comprehensive Income (USD $)	3 Months Ended		6 Months Ended
In Millions, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Net Income	$84	$110	$175	$264
Change in unrealized gains (losses) on investments available-for-sale, net of tax of $82, ($85), $123 and $39, respectively	153	-159	229	73
Net change in pension actuarial loss and prior service cost, net of tax of $0, $1, $0 and $2 respectively	0	2	-1	3
Change in life deferred acquisition costs, life policy reserves and other, net of tax of $0, $8, $0 and $8 respectively	1	16	0	16
Other comprehensive income (loss), net of tax	154	-141	228	92
Comprehensive Income (Loss)	$238	($31)	$403	$356

Condensed_Consolidated_Stateme2

Condensed Consolidated Statements of Comprehensive Income (Parenthetical) (USD $)	3 Months Ended		6 Months Ended
In Millions, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Statement of Comprehensive Income [Abstract]	'	'	'	'
Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, Tax	$82	($85)	$123	$39
Other Comprehensive Income Loss, Pension And Other Postretirement Benefit Plans, Net Actuarial Loss And Prior Service Cost Arising During Period, Tax	0	1	0	2
Other Comprehensive Income, Change in Life Deferred Acquisition Costs, Life Policy Reserves and Other, Tax	$0	$8	$0	$8

Condensed_Consolidated_Stateme3

Condensed Consolidated Statements of Shareholders' Equity (USD $)	Total	Common Stock	Paid-In Capital	Retained Earnings	Accumulated Other Comprehensive Income	Treasury Stock
In Millions
Balance at Dec. 31, 2012	$5,453	$394	$1,134	$4,021	$1,129	($1,225)
Balance (in shares) at Dec. 31, 2012	'	163	'	'	'	'
Net Income	264	'	'	264	'	'
Other comprehensive income, net	92	'	'	'	92	'
Dividends declared	-133	'	'	-133	'	'
Stock-based awards exercised and vested	'	2	'	'	'	'
Purchases	0	'	'	'	'	0
Stockholders' Equity, Other	23	'	28	'	'	-7
Balance at Jun. 30, 2013	5,699	396	1,162	4,152	1,221	-1,232
Balance (in shares) at Jun. 30, 2013	'	164	'	'	'	'
Balance at Dec. 31, 2013	6,070	397	1,191	4,268	1,504	-1,290
Balance (in shares) at Dec. 31, 2013	198	163	'	'	'	'
Net Income	175	'	'	175	'	'
Other comprehensive income, net	228	'	'	'	228	'
Dividends declared	-144	'	'	-144	'	'
Stock-based awards exercised and vested	'	0	'	'	'	'
Purchases	-7	'	'	'	'	-7
Stockholders' Equity, Other	21	'	7	'	'	14
Balance at Jun. 30, 2014	$6,343	$397	$1,198	$4,299	$1,732	($1,283)
Balance (in shares) at Jun. 30, 2014	198	164	'	'	'	'

Condensed_Consolidated_Stateme4

Condensed Consolidated Statements of Cash Flows (USD $)	6 Months Ended
In Millions, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013
Cash Flows From Operating Activities	'	'
Net Income	$175	$264
Adjustments to reconcile net income to net cash provided by operating activities:	'	'
Depreciation and amortization	25	20
Realized gains on investments, net	-36	-55
Stock-based compensation	10	10
Interest credited to contract holders	23	22
Deferred income tax expense	13	10
Changes in:	'	'
Investment income receivable	5	-1
Premiums and reinsurance receivable	-95	-103
Deferred policy acquisition costs	-19	-39
Other assets	-5	-10
Loss and loss expense reserves	133	54
Life policy reserves	76	33
Unearned premiums	134	155
Other liabilities	-72	-39
Current income tax receivable	-16	-70
Net cash provided by operating activities	351	251
Cash Flows From Investing Activities	'	'
Sale of fixed maturities	24	14
Call or maturity of fixed maturities	481	459
Sale of equity securities	82	157
Purchase of fixed maturities	-584	-666
Purchase of equity securities	-104	-190
Investment in finance receivables	-9	-18
Collection of finance receivables	15	14
Investment in buildings and equipment, net	-5	-3
Change in other invested assets, net	3	3
Net cash used in investing activities	-97	-230
Cash Flows From Financing Activities	'	'
Payment of cash dividends to shareholders	-138	-130
Purchase of treasury shares	7	0
Decrease in notes payable	-55	0
Proceeds from stock options exercised	11	12
Contract holders' funds deposited	45	45
Contract holders' funds withdrawn	-75	-55
Excess tax benefits on stock-based compensation	2	9
Other	-8	-7
Net cash used in financing activities	-225	-126
Net change in cash and cash equivalents	29	-105
Cash and cash equivalents at beginning of year	433	487
Cash and cash equivalents at end of period	462	382
Supplemental disclosures of cash flow information:	'	'
Interest paid	26	27
Income taxes paid	52	158
Non-cash activities:	'	'
Conversion of securities	7	54
Equipment acquired under capital lease obligations	7	17
Cashless exercise of stock options	$8	$15

Accounting_Policies

Accounting Policies	6 Months Ended
	Jun. 30, 2014
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, 2013, condensed consolidated balance sheet amounts are derived from the audited financial statements but do not include all disclosures required by GAAP.
	Our June 30, 2014, 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 2013 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, 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.
	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.

Investments

Investments	6 Months Ended
	Jun. 30, 2014
Investments [Abstract]	'
Investments	'
	INVESTMENTS
	The following table provides cost or amortized cost, gross unrealized gains, gross unrealized losses and fair value for our invested assets:
	(In millions)	Cost or
		amortized			Gross unrealized						Fair
	At June 30, 2014	cost			gains			losses			value
	Fixed maturity securities:
	States, municipalities and political subdivisions	$	3,205		$	170		$	5		$	3,370
	Convertibles and bonds with warrants attached	7			—			—			7
	United States government	7			—			—			7
	Government-sponsored enterprises	221			—			13			208
	Foreign government	10			—			—			10
	Commercial mortgage-backed	220			7			1			226
	Corporate	5,049			509			3			5,555
	Subtotal	8,719			686			22			9,383
	Equity securities:
	Common equities	2,458			1,992			3			4,447
	Nonredeemable preferred equities	124			35			1			158
	Subtotal	2,582			2,027			4			4,605
	Total	$	11,301		$	2,713		$	26		$	13,988
	At December 31, 2013
	Fixed maturity securities:
	States, municipalities and political subdivisions	$	3,107		$	125		$	21		$	3,211
	Convertibles and bonds with warrants attached	17			—			—			17
	United States government	7			—			—			7
	Government-sponsored enterprises	227			—			27			200
	Foreign government	10			—			—			10
	Commercial mortgage-backed	148			—			5			143
	Corporate	5,122			433			22			5,533
	Subtotal	8,638			558			75			9,121
	Equity securities:
	Common equities	2,396			1,818			1			4,213
	Nonredeemable preferred equities	127			38			3			162
	Subtotal	2,523			1,856			4			4,375
	Total	$	11,161		$	2,414		$	79		$	13,496
	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. The seven largest unrealized investment gains in our common stock portfolio are from Exxon Mobil Corporation (NYSE:XOM), Chevron Corporation (NYSE:CVX), Dover Corporation (NYSE:DOV), The Procter & Gamble Company (NYSE:PG), Honeywell International Incorporated (NYSE:HON), Johnson & Johnson (NYSE:JNJ), and RPM International (NYSE:RPM), which had a combined gross unrealized gain of $599 million. At June 30, 2014, we had $7 million fair value of hybrid securities included in fixed maturities that follow Accounting Standards Codification (ASC) 815-15-25, Accounting for Certain Hybrid Financial Instruments, compared with $18 million fair value of hybrid securities at December 31, 2013. The hybrid securities are carried at fair value, and the changes in fair value are included in realized investment gains and losses.
	The table below provides fair values and gross unrealized losses by investment category and by the duration of the securities’ continuous unrealized loss positions:
	(In millions)	Less than 12 months						12 months or more						Total		Total
		Fair			Unrealized			Fair			Unrealized			fair		unrealized
	At June 30, 2014	value			losses			value			losses			value		losses
	Fixed maturity securities:
	States, municipalities and political	$	61		$	1		$	267		$	4		$	328	$	5
	subdivisions
	United States government	—			—			1			—			1		—
	Government-sponsored enterprises	10			—			175			13			185		13
	Foreign government	—			—			10			—			10		—
	Commercial mortgage-backed	—			—			32			1			32		1
	Corporate	49			—			127			3			176		3
	Subtotal	120			1			612			21			732		22
	Equity securities:
	Common equities	39			—			79			3			118		3
	Nonredeemable preferred equities	5			—			17			1			22		1
	Subtotal	44			—			96			4			140		4
	Total	$	164		$	1		$	708		$	25		$	872	$	26
	At December 31, 2013
	Fixed maturity securities:
	States, municipalities and political	$	490		$	18		$	42		$	3		$	532	$	21
	subdivisions
	United States government	1			—			—			—			1		—
	Government-sponsored enterprises	199			27			1			—			200		27
	Foreign government	10			—			—			—			10		—
	Commercial mortgage-backed	125			5			—			—			125		5
	Corporate	572			20			43			2			615		22
	Subtotal	1,397			70			86			5			1,483		75
Equity securities:
Common equities	77			1			—			—			77		1
Nonredeemable preferred equities	42			3			—			—			42		3
Subtotal	119			4			—			—			119		4
Total	$	1,516		$	74		$	86		$	5		$	1,602	$	79
The following table provides investment income, realized investment gains and losses, the change in unrealized investment gains and losses, and other items:
(In millions)	Three months ended June 30,						Six months ended June 30,
	2014			2013			2014			2013
Investment income summary:
Interest on fixed maturities	$	103		$	103		$	207		$	205
Dividends on equity securities	34			30			66			57
Other investment income	1			—			2			1
Total	138			133			275			263
Less investment expenses	2			2			4			4
Total	$	136		$	131		$	271		$	259
Realized investment gains and losses summary:
Fixed maturities:
Gross realized gains	$	4		$	2		$	6		$	4
Gross realized losses	—			—			—			—
Other-than-temporary impairments	—			—			—			(2		)
Equity securities:
Gross realized gains	16			12			34			49
Gross realized losses	—			—			—			—
Other-than-temporary impairments	—			—			(1		)	—
Securities with embedded derivatives	(3		)	—			(4		)	1
Other	(3		)	—			1			3
Total	$	14		$	14		$	36		$	55
Change in unrealized gains and losses summary:
Fixed maturities	$	93		$	(282	)	$	181		$	(307	)
Equity securities	142			38			171			419
Net change in pension actuarial loss and prior	—			3			(1		)	5
service cost
Adjustment to deferred acquisition costs and life	(5		)	26			(8		)	29
policy reserves
Other	6			(2		)	8			(5		)
Income taxes on above	(82		)	76			(123		)	(49		)
Total	$	154		$	(141	)	$	228		$	92
During the three and six months ended June 30, 2014 and 2013, 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.
During the three months ended June 30, 2014, there was one equity security and no fixed-maturity securities other-than-temporarily impaired. During the six months ended June 30, 2014, there were three equity securities and one fixed-maturity security other-than-temporarily impaired. At June 30, 2014, 247 fixed-maturity investments with a total unrealized loss of $21 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. Four equity investments with a total unrealized loss of $4 million had been in an unrealized loss position for 12 months or more as of June 30, 2014. Of that total, no equity investments were trading below 70 percent of cost.
During 2013, we other-than-temporarily impaired seven fixed-maturity securities. At December 31, 2013, 40 fixed-maturity investments with a total unrealized loss of $5 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 no equity investments in an unrealized loss position for 12 months or more as of December 31, 2013.

Fair_Value_Measurements

Fair Value Measurements	6 Months Ended
	Jun. 30, 2014
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, 2013, and ultimately management determines fair value. See our 2013 Annual Report on Form 10-K, Item 8, Note 3, Fair Value Measurements, Page 121, 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 June 30, 2014, and December 31, 2013. We do not have any material liabilities carried at fair value. There were no transfers between Level 1 and Level 2.
	(In millions)		Quoted prices in			Significant other			Significant			Total
			active markets for			observable inputs			unobservable
			identical assets			(Level 2)			inputs
	At June 30, 2014		(Level 1)						(Level 3)
	Fixed maturities, available for sale:
	States, municipalities and political subdivisions		$	—		$	3,370		$	—		$	3,370
	Convertibles and bonds with warrants attached		—			7			—			7
	United States government		7			—			—			7
	Government-sponsored enterprises		—			208			—			208
	Foreign government		—			10			—			10
	Commercial mortgage-backed		—			226			—			226
	Corporate		—			5,546			9			5,555
	Subtotal		7			9,367			9			9,383
	Common equities, available for sale		4,447			—			—			4,447
	Nonredeemable preferred equities, available for sale		—			156			2			158
	Separate accounts taxable fixed maturities		—			719			—			719
	Top Hat Savings Plan mutual funds and common		17			—			—			17
	equity (included in Other assets)
	Total		$	4,471		$	10,242		$	11		$	14,724
	At December 31, 2013
	Fixed maturities, available for sale:
	States, municipalities and political subdivisions		$	—		$	3,211		$	—		$	3,211
	Convertibles and bonds with warrants attached		—			17			—			17
	United States government		7			—			—			7
	Government-sponsored enterprises		—			200			—			200
	Foreign government		—			10			—			10
	Commercial mortgage-backed		—			143			—			143
	Corporate		—			5,531			2			5,533
	Subtotal		7			9,112			2			9,121
	Common equities, available for sale		4,213			—			—			4,213
	Nonredeemable preferred equities, available for sale		—			160			2			162
	Separate accounts taxable fixed-maturities		—			682			—			682
	Top Hat Savings Plan mutual funds and common		14			—			—			14
	equity (included in Other assets)
	Total		$	4,234		$	9,954		$	4		$	14,192
	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 June 30, 2014. 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 tables provide the change in Level 3 assets for the three months ended June 30:
	(In millions)		Asset fair value measurements using significant unobservable inputs (Level 3)
			Corporate			Commercial			States,			Nonredeemable preferred			Total
			fixed			mortgage-			municipalities			equities
			maturities			backed fixed maturities			and political
									subdivisions
									fixed maturities
	Beginning balance, March 31, 2014		$	8		$	5		$	—		$	2		$	15
	Total gains or losses (realized/unrealized):
	Included in net income		—			—			—			—			—
	Included in other comprehensive income		—			—			—			—			—
	Purchases		—			—			—			—			—
	Sales		—			—			—			—			—
	Transfers into Level 3		1			—			—			—			1
	Transfers out of Level 3		—			(5		)	—			—			(5		)
	Ending balance, June 30, 2014		$	9		$	—		$	—		$	2		$	11
	Beginning balance, March 31, 2013		$	3		—			$	1		$	2		$	6
	Total gains or losses (realized/unrealized):
	Included in net income		—			—			—			—			—
	Included in other comprehensive income		—			—			—			—			—
	Purchases		—			—			—			—			—
	Sales		—			—			—			—			—
Transfers into Level 3		—			—			—			—			—
Transfers out of Level 3		—			—			—			—			—
Ending balance, June 30, 2013		$	3		—			$	1		$	2		$	6
The following tables provide the change in Level 3 assets for the six months ended June 30:
(In millions)	Asset fair value measurements using significant unobservable inputs (Level 3)
		Corporate			Commercial			States,			Nonredeemable preferred			Total
		fixed			mortgage-			municipalities			equities
		maturities			backed fixed maturities			and political
								subdivisions
								fixed maturities
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		7			5			—			—			12
Transfers out of Level 3		—			(5		)	—			—			(5		)
Ending balance, June 30, 2014		$	9		$	—		$	—		$	2		$	11
Beginning balance, January 1, 2013		$	3		$	—		$	1		$	1		$	5
Total gains or losses (realized/unrealized):
Included in net income		—			—			—			—			—
Included in other comprehensive income		—			—			—			—			—
Purchases		—			—			—			1			1
Sales		—			—			—			—			—
Transfers into Level 3		—			—			—			—			—
Transfers out of Level 3		—			—			—			—			—
Ending balance, June 30, 2013		$	3		$	—		$	1		$	2		$	6
Additional disclosures for the Level 3 category are not material.
Fair Value Disclosure 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:
(In millions)						Book value						Principal amount
						June 30,			December 31,			June 30,			December 31,
Interest rate			Year of issue			2014			2013			2014			2013
6.9	%		1998	Senior debentures, due 2028		$	28		$	28		$	28		$	28
6.92	%		2005	Senior debentures, due 2028		391			391			391			391
6.125	%		2004	Senior notes, due 2034		371			371			374			374
				Total		$	790		$	790		$	793		$	793
The following table shows fair values of our note payable and long-term debt subject to fair value disclosure requirements:
(In millions)		Quoted prices in			Significant other			Significant			Total
		active markets for			observable inputs			unobservable
		identical assets			(Level 2)			inputs
At June 30, 2014		(Level 1)						(Level 3)
Note payable		$	—		$	49		$	—		$	49
6.900% senior debentures, due 2028		—			34			—			34
6.920% senior debentures, due 2028		—			485			—			485
6.125% senior notes, due 2034		—			432			—			432
Total		$	—		$	1,000		$	—		$	1,000
At December 31, 2013
Note payable		$	—		$	104		$	—		$	104
6.900% senior debentures, due 2028		—			30			—			30
6.920% senior debentures, due 2028		—			458			—			458
6.125% senior notes, due 2034		—			399			—			399
Total		$	—		$	991		$	—		$	991
During the second quarter of 2014, we repaid $55 million on our revolving short-term line of credit as part of routine cash management.
The following table shows the fair value of our life policy loans, included in other invested assets, subject to fair value disclosure requirements:
(In millions)		Quoted prices in			Significant other			Significant			Total
		active markets for			observable inputs			unobservable
		identical assets			(Level 2)			inputs
At June 30, 2014		(Level 1)						(Level 3)
Life policy loans		$	—		$	—		$	43		$	43
At December 31, 2013
Life policy loans		$	—		$	—		$	45		$	45
Outstanding principal and interest for these life policy loans was $34 million and $36 million at June 30, 2014, and December 31, 2013, respectively.
The following table shows fair values of our deferred annuities and structured settlements, included in life policy and investment contract reserves, subject to fair value disclosure requirements:
(In millions)		Quoted prices in			Significant other			Significant			Total
		active markets for			observable inputs			unobservable
		identical assets			(Level 2)			inputs
At June 30, 2014		(Level 1)						(Level 3)
Deferred annuities		$	—		$	—		$	911		$	911
Structured settlements		—			218			—			218
Total		$	—		$	218		$	911		$	1,129
At December 31, 2013
Deferred annuities		$	—		$	—		$	911		$	911
Structured settlements		—			219			—			219
Total		$	—		$	219		$	911		$	1,130
Recorded reserves for the deferred annuities were $865 million and $862 million at June 30, 2014, and December 31, 2013, respectively. Recorded reserves for the structured settlements were $184 million and $189 million at June 30, 2014, and December 31, 2013, respectively.

Property_Casualty_Loss_and_Los

Property Casualty Loss and Loss Expenses	6 Months Ended
	Jun. 30, 2014
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:
	(In millions)	Three months ended June 30,						Six months ended June 30,
		2014			2013			2014			2013
	Gross loss and loss expense reserves, beginning	$	4,323		$	4,173		$	4,241		$	4,169
	of period
	Less reinsurance receivable	289			349			299			356
	Net loss and loss expense reserves, beginning of	4,034			3,824			3,942			3,813
	period
	Net incurred loss and loss expenses related to:
	Current accident year	773			675			1,478			1,209
	Prior accident years	(66		)	(92		)	(95		)	(102		)
	Total incurred	707			583			1,383			1,107
	Net paid loss and loss expenses related to:
	Current accident year	309			249			506			370
	Prior accident years	306			272			693			664
	Total paid	615			521			1,199			1,034
	Net loss and loss expense reserves, end of period	4,126			3,886			4,126			3,886
	Plus reinsurance receivable	282			333			282			333
	Gross loss and loss expense reserves, end of	$	4,408		$	4,219		$	4,408		$	4,219
	period
	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 $36 million at June 30, 2014, and $65 million at June 30, 2013, for certain life and health loss and loss expense reserves.
	For the three months ended June 30, 2014, we experienced $66 million of favorable development on prior accident years, including $57 million of favorable development in commercial lines, $1 million of favorable development in personal lines and $8 million favorable development in excess and surplus lines. This included $5 million from favorable development of catastrophe losses for the three months ended June 30, 2014, compared with $8 million of favorable development of catastrophe losses for the three months ended June 30, 2013. We recognized favorable reserve development during the three months ended June 30, 2014 of $24 million for the commercial casualty line and $22 million for the commercial property line due to reduced uncertainty of prior accident year loss and loss adjustment expense for these lines.
	For the six months ended June 30, 2014, we experienced $95 million of favorable development on prior accident years, including $60 million of favorable development in commercial lines, $18 million of favorable development in personal lines and $17 million favorable development in excess and surplus lines. This included
	$14 million from favorable development of catastrophe losses for the six months ended June 30, 2014, compared with $15 million of favorable development of catastrophe losses for the six months ended June 30, 2013. We recognized favorable reserve development during the six months ended June 30, 2014, of $24 million for the commercial property line and $30 million for the workers' compensation line due to reduced uncertainty of prior accident year loss and loss adjustment expense for these lines.

Life_Policy_and_Investment_Con

Life Policy and Investment Contract Reserves	6 Months Ended
	Jun. 30, 2014
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:
	(In millions)	June 30,		December 31, 2013
		2014
	Ordinary/traditional life	$	848	$	815
	Universal life	511		508
	Deferred annuities	865		862
	Structured settlements	184		189
	Other	46		16
	Total life policy and investment contract reserves	$	2,454	$	2,390

Deferred_Acquisition_Costs

Deferred Acquisition Costs	6 Months Ended
	Jun. 30, 2014
Deferred Costs [Abstract]	'
Deferred Acquisition Costs	'
	DEFERRED 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.
	(In millions)	Three months ended June 30,						Six months ended June 30,
		2014			2013			2014			2013
	Deferred policy acquisition costs asset, beginning of	$	564		$	491		$	565		$	470
	period
	Capitalized deferred policy acquisition costs	216			203			422			401
	Amortized deferred policy acquisition costs	(202		)	(183		)	(403		)	(362		)
	Amortized shadow deferred policy acquisition costs	(7		)	35			(13		)	37
	Deferred policy acquisition costs asset, end of	$	571		$	546		$	571		$	546
	period
	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_Comprehensiv

Accumulated Other Comprehensive Income	6 Months Ended
	Jun. 30, 2014
Accumulated Other Comprehensive Income [Abstract]	'
Comprehensive Income (Loss) Note	'
	ACCUMULATED OTHER COMPREHENSIVE INCOME
	Accumulated other comprehensive income includes changes in unrealized gains and losses on investments available for sale and other invested assets, changes in pension obligations and changes in life deferred acquisition costs, life policy reserves and other as follows:
	(In millions)	Three months ended June 30,
		2014									2013
		Before tax			Income tax			Net			Before tax			Income tax			Net
	Accumulated unrealized gains, net, on investments available for sale,	$	2,452		$	849		$	1,603		$	2,231		$	771		$	1,460
	beginning of period
	Other comprehensive income before reclassification	252			87			165			(230		)	(81		)	(149		)
	Reclassification adjustment for realized investment gains, net,	(17		)	(5		)	(12		)	(14		)	(4		)	(10		)
	included in net income
	Effect on other comprehensive income	235			82			153			(244		)	(85		)	(159		)
	Accumulated unrealized gains, net, on investments available for sale,	$	2,687		$	931		$	1,756		$	1,987		$	686		$	1,301
	end of period
	Accumulated unrealized losses, net, for pension obligations,	$	(19	)	$	(6	)	$	(13	)	$	(99	)	$	(34	)	$	(65	)
	beginning of period
	Other comprehensive income before reclassification	—			—			—						—			—
	Reclassification adjustment for amortization of actuarial loss and prior	—			—			—			3			1			2
	service cost, net, included in net income
	Effect on other comprehensive income	—			—			—			3			1			2
	Accumulated unrealized losses, net, for pension obligations,	$	(19	)	$	(6	)	$	(13	)	$	(96	)	$	(33	)	$	(63	)
	end of period
	Accumulated unrealized losses, net, on life deferred acquisition costs,	$	(17	)	$	(5	)	$	(12	)	$	(50	)	$	(17	)	$	(33	)
	life policy reserves and other, beginning of period
	Other comprehensive income before reclassification	(2		)	—			(2		)	27			10			17
	Reclassification adjustment for life deferred acquisition costs,	3			—			3			(3		)	(2		)	(1		)
	life policy reserves and other, net, included in net income
	Effect on other comprehensive income	1			—			1			24			8			16
	Accumulated unrealized losses, net, on life deferred acquisition costs,	$	(16	)	$	(5	)	$	(11	)	$	(26	)	$	(9	)	$	(17	)
	life policy reserves and other, end of period
	Accumulated other comprehensive income, beginning of period	$	2,416		$	838		$	1,578		$	2,082		$	720		$	1,362
	Change in unrealized gains, net, on investments available for sale	235			82			153			(244		)	(85		)	(159		)
	Change in pension obligations	—			—			—			3			1			2
	Change in life deferred acquisition costs, life policy reserves	1			—			1			24			8			16
	and other
	Effect on other comprehensive income	236			82			154			(217		)	(76		)	(141		)
	Accumulated other comprehensive income, end of period	$	2,652		$	920		$	1,732		$	1,865		$	644		$	1,221
	(In millions)	Six months ended June 30,
		2014									2013
		Before tax			Income tax			Net			Before tax			Income tax			Net
	Accumulated unrealized gains, net, on investments available for sale,	$	2,335		$	808		$	1,527		$	1,875		$	647		$	1,228
	beginning of period
	Other comprehensive income before reclassification	387			135			252			164			56			108
	Reclassification adjustment for realized investment gains, net,	(35		)	(12		)	(23		)	(52		)	(17		)	(35		)
	included in net income
	Effect on other comprehensive income	352			123			229			112			39			73
	Accumulated unrealized gains, net, on investments available for sale,	$	2,687		$	931		$	1,756		$	1,987		$	686		$	1,301
	end of period
	Accumulated unrealized losses, net, for pension obligations,	$	(18	)	$	(6	)	$	(12	)	$	(101	)	$	(35	)	$	(66	)
	beginning of period
	Other comprehensive income before reclassification	—			—			—			—			—			—
	Reclassification adjustment for amortization of actuarial loss and prior	(1		)	—			(1		)	5			2			3
	service cost, net, included in net income
	Effect on other comprehensive income	(1		)	—			(1		)	5			2			3
	Accumulated unrealized losses, net, for pension obligations,	$	(19	)	$	(6	)	$	(13	)	$	(96	)	$	(33	)	$	(63	)
	end of period
	Accumulated unrealized losses, net, on life deferred acquisition costs,	$	(16	)	$	(5	)	$	(11	)	$	(50	)	$	(17	)	$	(33	)
	life policy reserves and other, beginning of period
	Other comprehensive income before reclassification	1			1			—			27			10			17
	Reclassification adjustment for life deferred acquisition costs,	(1		)	(1		)	—			(3		)	(2		)	(1		)
	life policy reserves and other, net, included in net income
	Effect on other comprehensive income	—			—			—			24			8			16
	Accumulated unrealized losses, net, on life deferred acquisition costs,	$	(16	)	$	(5	)	$	(11	)	$	(26	)	$	(9	)	$	(17	)
	life policy reserves and other, end of period
Accumulated other comprehensive income, beginning of period	$	2,301		$	797		$	1,504		$	1,724		$	595		$	1,129
Change in unrealized gains, net, on investments available for sale	352			123			229			112			39			73
Change in pension obligations	(1		)	—			(1		)	5			2			3
Change in life deferred acquisition costs, life policy reserves	—			—			—			24			8			16
and other
Effect on other comprehensive income	351			123			228			141			49			92
Accumulated other comprehensive income, end of period	$	2,652		$	920		$	1,732		$	1,865		$	644		$	1,221
The reclassification adjustment for realized gains on investments available for sale and life deferred acquisition costs, life policy reserves and other is recorded in the total realized investment gains, net, line item of the condensed consolidated statements of income.

Reinsurance

Reinsurance	6 Months Ended
	Jun. 30, 2014
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.
	Primary components of our property casualty reinsurance program include a property per risk treaty, property excess treaty, casualty per occurrence treaty, casualty excess treaty, property catastrophe treaty and catastrophe bonds.
	Our condensed consolidated statements of income include earned consolidated property casualty insurance premiums on assumed and ceded business:
	(In millions)	Three months ended June 30,						Six months ended June 30,
		2014			2013			2014			2013
	Direct earned premiums	$	1,048		$	958		$	2,067		$	1,893
	Assumed earned premiums	2			3			5			5
	Ceded earned premiums	(44		)	(51		)	(87		)	(99		)
	Net earned premiums	$	1,006		$	910		$	1,985		$	1,799
	Our condensed consolidated statements of income include incurred consolidated property casualty insurance loss and loss expenses on assumed and ceded business:
	(In millions)	Three months ended June 30,						Six months ended June 30,
		2014			2013			2014			2013
	Direct incurred loss and loss expenses	$	716		$	593		$	1,393		$	1,128
	Assumed incurred loss and loss expenses	2			5			4			7
	Ceded incurred loss and loss expenses	(11		)	(15		)	(14		)	(28		)
	Net incurred loss and loss expenses	$	707		$	583		$	1,383		$	1,107
	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:
	(In millions)	Three months ended June 30,						Six months ended June 30,
		2014			2013			2014			2013
	Direct earned premiums	$	68		$	58		$	130		$	114
	Ceded earned premiums	(15		)	(14		)	(29		)	(28		)
	Net earned premiums	$	53		$	44		$	101		$	86
	Our condensed consolidated statements of income include life insurance contract holders' benefits incurred on ceded business:
	(In millions)	Three months ended June 30,						Six months ended June 30,
		2014			2013			2014			2013
	Direct contract holders' benefits incurred	$	68		$	62		$	148		$	126
	Ceded contract holders' benefits incurred	(12		)	(14		)	(36		)	(34		)
	Net contract holders' benefits incurred	$	56		$	48		$	112		$	92
	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	6 Months Ended
	Jun. 30, 2014
Income Tax Disclosure [Abstract]	'
Income Taxes	'
	INCOME TAXES
	As of June 30, 2014, and December 31, 2013, we had no liability for unrecognized tax benefits.
	The differences between the 35 percent statutory income tax rate and our effective income tax rate were as follows:
	(In millions)	Three months ended June 30,										Six months ended June 30,
		2014					2013					2014					2013
	Tax at statutory rate	$	37		35	%	$	52		35	%	$	79		35	%	$	128		35	%
	Increase (decrease) resulting from:
	Tax-exempt income from municipal bonds	(8		)	(7.5	)	(9		)	(6.1	)	(16		)	(7.1	)	(16		)	(4.4	)
	Dividend received exclusion	(7		)	(6.5	)	(6		)	(4.2	)	(14		)	(6.2	)	(12		)	(3.3	)
	Other	1			0.5		1			1		2			0.9		1			0.4
	Provision for income taxes	$	23		21.5	%	$	38		25.7	%	$	51		22.6	%	$	101		27.7	%
	The change in our effective tax rate was primarily due to changes in pretax income from underwriting results and realized investment gains and losses, compared with immaterial changes in the amount of permanent book-tax differences.

Net_Income_Per_Common_Share

Net Income Per Common Share	6 Months Ended
	Jun. 30, 2014
Earnings Per Share [Abstract]	'
Net Income Per Common Share	'
	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 June 30,				Six months ended June 30,
		2014		2013		2014		2013
	Numerator:
	Net income—basic and diluted	$	84	$	110	$	175	$	264
	Denominator:
	Basic weighted-average common shares outstanding	163.5		163.5		163.5		163.3
	Effect of stock-based awards:
	Stock options	1		1.2		1		1.1
	Nonvested shares	0.6		0.7		0.6		0.7
	Adjusted diluted weighted-average shares	165.1		165.4		165.1		165.2
	Earnings per share:
	Basic	$	0.51	$	0.67	$	1.07	$	1.62
	Diluted	0.51		0.66		1.06		1.6
	Number of anti-dilutive share-based awards	0.7		0.3		0.7		0.4
	The sources of dilution of our common shares are certain equity-based awards. See our 2013 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 six months ended June 30, 2014 and 2013. 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	6 Months Ended
	Jun. 30, 2014
Compensation and Retirement Disclosure [Abstract]	'
Employee Retirement Benefits	'
	EMPLOYEE RETIREMENT BENEFITS
	The following summarizes the components of net periodic costs for our qualified and supplemental pension plans:
	(In millions)	Three months ended June 30,						Six months ended June 30,
		2014			2013			2014			2013
	Service cost	$	3		$	3		$	5		$	6
	Interest cost	3			3			7			6
	Expected return on plan assets	(4		)	(4		)	(8		)	(8		)
	Amortization of actuarial loss and prior service cost	0			3			1			5
	Net periodic benefit cost	$	2		$	5		$	5		$	9
	See our 2013 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 of $2 million to our 401(k) and Top Hat savings plans during both the second quarter of 2014 and 2013 and contributions of $6 million and $5 million for the first six months of 2014 and 2013, respectively.
	We contributed $5 million to our qualified pension plan during the first quarter of 2014. We do not anticipate further contributions to our qualified pension plan during the remainder of 2014.

Commitments_and_Contingent_Lia

Commitments and Contingent Liabilities	6 Months Ended
	Jun. 30, 2014
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 adjustment 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 data bases 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 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	6 Months Ended
	Jun. 30, 2014
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:
	•	Commercial lines property casualty insurance
	•	Personal lines property casualty insurance
	•	Excess and surplus lines property casualty insurance
	•	Life insurance
	•	Investments
	We report as Other the noninvestment operations of the parent company and its noninsurer subsidiary, CFC Investment Company. See our 2013 Annual Report on Form 10-K, Item 8, Note 18, Segment Information, Page 156, 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:
	(In millions)		Three months ended June 30,						Six months ended June 30,
			2014			2013			2014			2013
	Revenues:
	Commercial lines insurance
	Commercial casualty		$	234		$	211		$	458		$	415
	Commercial property		180			152			351			299
	Commercial auto		132			117			258			231
	Workers' compensation		95			87			187			175
	Specialty packages		30			37			66			76
	Management liability and surety		31			30			62			59
	Machinery and equipment		12			11			24			21
	Commercial lines insurance premiums		714			645			1,406			1,276
	Fee revenue		1			1			2			1
	Total commercial lines insurance		715			646			1,408			1,277
	Personal lines insurance
	Personal auto		117			109			233			216
	Homeowner		111			99			220			195
	Other personal lines		30			29			59			57
	Personal lines insurance premiums		258			237			512			468
	Fee revenue		1			1			1			1
	Total personal lines insurance		259			238			513			469
	Excess and surplus lines insurance		34			28			67			55
	Life insurance premiums		53			44			101			86
	Separate account investment management fees		1			1			3			2
	Total life insurance		54			45			104			88
	Investment operations
	Investment income, net of expenses		136			131			271			259
	Realized investment gains, net		14			14			36			55
	Total investments		150			145			307			314
	Other		2			2			4			4
	Total revenues		$	1,214		$	1,104		$	2,403		$	2,207
	Income (loss) before income taxes:
	Insurance underwriting results
	Commercial lines insurance		$	28		$	34		$	30		$	92
	Personal lines insurance		(40		)	(1		)	(47		)	19
	Excess and surplus lines insurance		5			1			9			1
	Life insurance		(1		)	3			(1		)	10
	Investment operations		130			127			266			275
	Other		(15		)	(16		)	(31		)	(32		)
	Total income before income taxes		$	107		$	148		$	226		$	365
	Identifiable assets:		June 30,			December 31, 2013
			2014
	Property casualty insurance		$	2,636		$	2,455
	Life insurance		1,263			1,225
	Investment operations		14,104			13,618
	Other		332			364
	Total		$	18,335		$	17,662

Accounting_Policies_Pending_Ac

Accounting Policies Pending Accounting Updates (Policies)	6 Months Ended
	Jun. 30, 2014
Accounting Policies [Abstract]	'
Revenue Recognition, Policy [Policy Text Block]	'
	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, 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.
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.

Investments_Tables

Investments (Tables)	6 Months Ended
	Jun. 30, 2014
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 invested assets:
	(In millions)	Cost or
		amortized			Gross unrealized						Fair
	At June 30, 2014	cost			gains			losses			value
	Fixed maturity securities:
	States, municipalities and political subdivisions	$	3,205		$	170		$	5		$	3,370
	Convertibles and bonds with warrants attached	7			—			—			7
	United States government	7			—			—			7
	Government-sponsored enterprises	221			—			13			208
	Foreign government	10			—			—			10
	Commercial mortgage-backed	220			7			1			226
	Corporate	5,049			509			3			5,555
	Subtotal	8,719			686			22			9,383
	Equity securities:
	Common equities	2,458			1,992			3			4,447
	Nonredeemable preferred equities	124			35			1			158
	Subtotal	2,582			2,027			4			4,605
	Total	$	11,301		$	2,713		$	26		$	13,988
	At December 31, 2013
	Fixed maturity securities:
	States, municipalities and political subdivisions	$	3,107		$	125		$	21		$	3,211
	Convertibles and bonds with warrants attached	17			—			—			17
	United States government	7			—			—			7
	Government-sponsored enterprises	227			—			27			200
	Foreign government	10			—			—			10
	Commercial mortgage-backed	148			—			5			143
	Corporate	5,122			433			22			5,533
	Subtotal	8,638			558			75			9,121
	Equity securities:
	Common equities	2,396			1,818			1			4,213
	Nonredeemable preferred equities	127			38			3			162
	Subtotal	2,523			1,856			4			4,375
	Total	$	11,161		$	2,414		$	79		$	13,496
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:
	(In millions)	Less than 12 months						12 months or more						Total		Total
		Fair			Unrealized			Fair			Unrealized			fair		unrealized
	At June 30, 2014	value			losses			value			losses			value		losses
	Fixed maturity securities:
	States, municipalities and political	$	61		$	1		$	267		$	4		$	328	$	5
	subdivisions
	United States government	—			—			1			—			1		—
	Government-sponsored enterprises	10			—			175			13			185		13
	Foreign government	—			—			10			—			10		—
	Commercial mortgage-backed	—			—			32			1			32		1
	Corporate	49			—			127			3			176		3
	Subtotal	120			1			612			21			732		22
	Equity securities:
	Common equities	39			—			79			3			118		3
	Nonredeemable preferred equities	5			—			17			1			22		1
	Subtotal	44			—			96			4			140		4
	Total	$	164		$	1		$	708		$	25		$	872	$	26
	At December 31, 2013
	Fixed maturity securities:
	States, municipalities and political	$	490		$	18		$	42		$	3		$	532	$	21
	subdivisions
	United States government	1			—			—			—			1		—
	Government-sponsored enterprises	199			27			1			—			200		27
	Foreign government	10			—			—			—			10		—
	Commercial mortgage-backed	125			5			—			—			125		5
	Corporate	572			20			43			2			615		22
	Subtotal	1,397			70			86			5			1,483		75
	Equity securities:
	Common equities	77			1			—			—			77		1
	Nonredeemable preferred equities	42			3			—			—			42		3
	Subtotal	119			4			—			—			119		4
	Total	$	1,516		$	74		$	86		$	5		$	1,602	$	79
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:
	(In millions)	Three months ended June 30,						Six months ended June 30,
		2014			2013			2014			2013
	Investment income summary:
	Interest on fixed maturities	$	103		$	103		$	207		$	205
	Dividends on equity securities	34			30			66			57
	Other investment income	1			—			2			1
	Total	138			133			275			263
	Less investment expenses	2			2			4			4
	Total	$	136		$	131		$	271		$	259
	Realized investment gains and losses summary:
	Fixed maturities:
	Gross realized gains	$	4		$	2		$	6		$	4
	Gross realized losses	—			—			—			—
	Other-than-temporary impairments	—			—			—			(2		)
	Equity securities:
	Gross realized gains	16			12			34			49
	Gross realized losses	—			—			—			—
	Other-than-temporary impairments	—			—			(1		)	—
	Securities with embedded derivatives	(3		)	—			(4		)	1
	Other	(3		)	—			1			3
	Total	$	14		$	14		$	36		$	55
	Change in unrealized gains and losses summary:
	Fixed maturities	$	93		$	(282	)	$	181		$	(307	)
	Equity securities	142			38			171			419
	Net change in pension actuarial loss and prior	—			3			(1		)	5
	service cost
	Adjustment to deferred acquisition costs and life	(5		)	26			(8		)	29
	policy reserves
	Other	6			(2		)	8			(5		)
	Income taxes on above	(82		)	76			(123		)	(49		)
	Total	$	154		$	(141	)	$	228		$	92

Fair_Value_Measurements_Tables

Fair Value Measurements (Tables)	6 Months Ended
	Jun. 30, 2014
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 June 30, 2014, and December 31, 2013. We do not have any material liabilities carried at fair value. There were no transfers between Level 1 and Level 2.
	(In millions)		Quoted prices in			Significant other			Significant			Total
			active markets for			observable inputs			unobservable
			identical assets			(Level 2)			inputs
	At June 30, 2014		(Level 1)						(Level 3)
	Fixed maturities, available for sale:
	States, municipalities and political subdivisions		$	—		$	3,370		$	—		$	3,370
	Convertibles and bonds with warrants attached		—			7			—			7
	United States government		7			—			—			7
	Government-sponsored enterprises		—			208			—			208
	Foreign government		—			10			—			10
	Commercial mortgage-backed		—			226			—			226
	Corporate		—			5,546			9			5,555
	Subtotal		7			9,367			9			9,383
	Common equities, available for sale		4,447			—			—			4,447
	Nonredeemable preferred equities, available for sale		—			156			2			158
	Separate accounts taxable fixed maturities		—			719			—			719
	Top Hat Savings Plan mutual funds and common		17			—			—			17
	equity (included in Other assets)
	Total		$	4,471		$	10,242		$	11		$	14,724
	At December 31, 2013
	Fixed maturities, available for sale:
	States, municipalities and political subdivisions		$	—		$	3,211		$	—		$	3,211
	Convertibles and bonds with warrants attached		—			17			—			17
	United States government		7			—			—			7
	Government-sponsored enterprises		—			200			—			200
	Foreign government		—			10			—			10
	Commercial mortgage-backed		—			143			—			143
	Corporate		—			5,531			2			5,533
	Subtotal		7			9,112			2			9,121
	Common equities, available for sale		4,213			—			—			4,213
	Nonredeemable preferred equities, available for sale		—			160			2			162
	Separate accounts taxable fixed-maturities		—			682			—			682
	Top Hat Savings Plan mutual funds and common		14			—			—			14
	equity (included in Other assets)
	Total		$	4,234		$	9,954		$	4		$	14,192
Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3)	'
	The following tables provide the change in Level 3 assets for the three months ended June 30:
	(In millions)		Asset fair value measurements using significant unobservable inputs (Level 3)
			Corporate			Commercial			States,			Nonredeemable preferred			Total
			fixed			mortgage-			municipalities			equities
			maturities			backed fixed maturities			and political
									subdivisions
									fixed maturities
	Beginning balance, March 31, 2014		$	8		$	5		$	—		$	2		$	15
	Total gains or losses (realized/unrealized):
	Included in net income		—			—			—			—			—
	Included in other comprehensive income		—			—			—			—			—
	Purchases		—			—			—			—			—
	Sales		—			—			—			—			—
	Transfers into Level 3		1			—			—			—			1
	Transfers out of Level 3		—			(5		)	—			—			(5		)
	Ending balance, June 30, 2014		$	9		$	—		$	—		$	2		$	11
	Beginning balance, March 31, 2013		$	3		—			$	1		$	2		$	6
	Total gains or losses (realized/unrealized):
	Included in net income		—			—			—			—			—
	Included in other comprehensive income		—			—			—			—			—
	Purchases		—			—			—			—			—
	Sales		—			—			—			—			—
	Transfers into Level 3		—			—			—			—			—
	Transfers out of Level 3		—			—			—			—			—
	Ending balance, June 30, 2013		$	3		—			$	1		$	2		$	6
	The following tables provide the change in Level 3 assets for the six months ended June 30:
	(In millions)	Asset fair value measurements using significant unobservable inputs (Level 3)
			Corporate			Commercial			States,			Nonredeemable preferred			Total
			fixed			mortgage-			municipalities			equities
			maturities			backed fixed maturities			and political
									subdivisions
									fixed maturities
	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		7			5			—			—			12
	Transfers out of Level 3		—			(5		)	—			—			(5		)
	Ending balance, June 30, 2014		$	9		$	—		$	—		$	2		$	11
	Beginning balance, January 1, 2013		$	3		$	—		$	1		$	1		$	5
	Total gains or losses (realized/unrealized):
	Included in net income		—			—			—			—			—
	Included in other comprehensive income		—			—			—			—			—
	Purchases		—			—			—			1			1
	Sales		—			—			—			—			—
	Transfers into Level 3		—			—			—			—			—
	Transfers out of Level 3		—			—			—			—			—
	Ending balance, June 30, 2013		$	3		$	—		$	1		$	2		$	6
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:
	(In millions)						Book value						Principal amount
							June 30,			December 31,			June 30,			December 31,
	Interest rate			Year of issue			2014			2013			2014			2013
	6.9	%		1998	Senior debentures, due 2028		$	28		$	28		$	28		$	28
	6.92	%		2005	Senior debentures, due 2028		391			391			391			391
	6.125	%		2004	Senior notes, due 2034		371			371			374			374
					Total		$	790		$	790		$	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, subject to fair value disclosure requirements:
	(In millions)		Quoted prices in			Significant other			Significant			Total
			active markets for			observable inputs			unobservable
			identical assets			(Level 2)			inputs
	At June 30, 2014		(Level 1)						(Level 3)
	Life policy loans		$	—		$	—		$	43		$	43
	At December 31, 2013
	Life policy loans		$	—		$	—		$	45		$	45
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 subject to fair value disclosure requirements:
	(In millions)		Quoted prices in			Significant other			Significant			Total
			active markets for			observable inputs			unobservable
			identical assets			(Level 2)			inputs
	At June 30, 2014		(Level 1)						(Level 3)
	Note payable		$	—		$	49		$	—		$	49
	6.900% senior debentures, due 2028		—			34			—			34
	6.920% senior debentures, due 2028		—			485			—			485
	6.125% senior notes, due 2034		—			432			—			432
	Total		$	—		$	1,000		$	—		$	1,000
	At December 31, 2013
	Note payable		$	—		$	104		$	—		$	104
	6.900% senior debentures, due 2028		—			30			—			30
	6.920% senior debentures, due 2028		—			458			—			458
	6.125% senior notes, due 2034		—			399			—			399
	Total		$	—		$	991		$	—		$	991
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, subject to fair value disclosure requirements:
	(In millions)		Quoted prices in			Significant other			Significant			Total
			active markets for			observable inputs			unobservable
			identical assets			(Level 2)			inputs
	At June 30, 2014		(Level 1)						(Level 3)
	Deferred annuities		$	—		$	—		$	911		$	911
	Structured settlements		—			218			—			218
	Total		$	—		$	218		$	911		$	1,129
	At December 31, 2013
	Deferred annuities		$	—		$	—		$	911		$	911
	Structured settlements		—			219			—			219
	Total		$	—		$	219		$	911		$	1,130

Property_Casualty_Loss_and_Los1

Property Casualty Loss and Loss Expenses (Tables)	6 Months Ended
	Jun. 30, 2014
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:
	(In millions)	Three months ended June 30,						Six months ended June 30,
		2014			2013			2014			2013
	Gross loss and loss expense reserves, beginning	$	4,323		$	4,173		$	4,241		$	4,169
	of period
	Less reinsurance receivable	289			349			299			356
	Net loss and loss expense reserves, beginning of	4,034			3,824			3,942			3,813
	period
	Net incurred loss and loss expenses related to:
	Current accident year	773			675			1,478			1,209
	Prior accident years	(66		)	(92		)	(95		)	(102		)
	Total incurred	707			583			1,383			1,107
	Net paid loss and loss expenses related to:
	Current accident year	309			249			506			370
	Prior accident years	306			272			693			664
	Total paid	615			521			1,199			1,034
	Net loss and loss expense reserves, end of period	4,126			3,886			4,126			3,886
	Plus reinsurance receivable	282			333			282			333
	Gross loss and loss expense reserves, end of	$	4,408		$	4,219		$	4,408		$	4,219
	period

Life_Policy_and_Investment_Con1

Life Policy and Investment Contract Reserves (Tables)	6 Months Ended
	Jun. 30, 2014
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:
	(In millions)	June 30,		December 31, 2013
		2014
	Ordinary/traditional life	$	848	$	815
	Universal life	511		508
	Deferred annuities	865		862
	Structured settlements	184		189
	Other	46		16
	Total life policy and investment contract reserves	$	2,454	$	2,390

Deferred_Acquisition_Costs_Tab

Deferred Acquisition Costs (Tables)	6 Months Ended
	Jun. 30, 2014
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.
	(In millions)	Three months ended June 30,						Six months ended June 30,
		2014			2013			2014			2013
	Deferred policy acquisition costs asset, beginning of	$	564		$	491		$	565		$	470
	period
	Capitalized deferred policy acquisition costs	216			203			422			401
	Amortized deferred policy acquisition costs	(202		)	(183		)	(403		)	(362		)
	Amortized shadow deferred policy acquisition costs	(7		)	35			(13		)	37
	Deferred policy acquisition costs asset, end of	$	571		$	546		$	571		$	546
	period

Accumulated_Other_Comprehensiv1

Accumulated Other Comprehensive Income (Tables)	6 Months Ended
	Jun. 30, 2014
Accumulated Other Comprehensive Income [Abstract]	'
Schedule of Accumulated Other Comprehensive Income (Loss)	'
	(In millions)	Three months ended June 30,
		2014									2013
		Before tax			Income tax			Net			Before tax			Income tax			Net
	Accumulated unrealized gains, net, on investments available for sale,	$	2,452		$	849		$	1,603		$	2,231		$	771		$	1,460
	beginning of period
	Other comprehensive income before reclassification	252			87			165			(230		)	(81		)	(149		)
	Reclassification adjustment for realized investment gains, net,	(17		)	(5		)	(12		)	(14		)	(4		)	(10		)
	included in net income
	Effect on other comprehensive income	235			82			153			(244		)	(85		)	(159		)
	Accumulated unrealized gains, net, on investments available for sale,	$	2,687		$	931		$	1,756		$	1,987		$	686		$	1,301
	end of period
	Accumulated unrealized losses, net, for pension obligations,	$	(19	)	$	(6	)	$	(13	)	$	(99	)	$	(34	)	$	(65	)
	beginning of period
	Other comprehensive income before reclassification	—			—			—						—			—
	Reclassification adjustment for amortization of actuarial loss and prior	—			—			—			3			1			2
	service cost, net, included in net income
	Effect on other comprehensive income	—			—			—			3			1			2
	Accumulated unrealized losses, net, for pension obligations,	$	(19	)	$	(6	)	$	(13	)	$	(96	)	$	(33	)	$	(63	)
	end of period
	Accumulated unrealized losses, net, on life deferred acquisition costs,	$	(17	)	$	(5	)	$	(12	)	$	(50	)	$	(17	)	$	(33	)
	life policy reserves and other, beginning of period
	Other comprehensive income before reclassification	(2		)	—			(2		)	27			10			17
	Reclassification adjustment for life deferred acquisition costs,	3			—			3			(3		)	(2		)	(1		)
	life policy reserves and other, net, included in net income
	Effect on other comprehensive income	1			—			1			24			8			16
	Accumulated unrealized losses, net, on life deferred acquisition costs,	$	(16	)	$	(5	)	$	(11	)	$	(26	)	$	(9	)	$	(17	)
	life policy reserves and other, end of period
	Accumulated other comprehensive income, beginning of period	$	2,416		$	838		$	1,578		$	2,082		$	720		$	1,362
	Change in unrealized gains, net, on investments available for sale	235			82			153			(244		)	(85		)	(159		)
	Change in pension obligations	—			—			—			3			1			2
	Change in life deferred acquisition costs, life policy reserves	1			—			1			24			8			16
	and other
	Effect on other comprehensive income	236			82			154			(217		)	(76		)	(141		)
	Accumulated other comprehensive income, end of period	$	2,652		$	920		$	1,732		$	1,865		$	644		$	1,221
	(In millions)	Six months ended June 30,
		2014									2013
		Before tax			Income tax			Net			Before tax			Income tax			Net
	Accumulated unrealized gains, net, on investments available for sale,	$	2,335		$	808		$	1,527		$	1,875		$	647		$	1,228
	beginning of period
	Other comprehensive income before reclassification	387			135			252			164			56			108
	Reclassification adjustment for realized investment gains, net,	(35		)	(12		)	(23		)	(52		)	(17		)	(35		)
	included in net income
	Effect on other comprehensive income	352			123			229			112			39			73
	Accumulated unrealized gains, net, on investments available for sale,	$	2,687		$	931		$	1,756		$	1,987		$	686		$	1,301
	end of period
	Accumulated unrealized losses, net, for pension obligations,	$	(18	)	$	(6	)	$	(12	)	$	(101	)	$	(35	)	$	(66	)
	beginning of period
	Other comprehensive income before reclassification	—			—			—			—			—			—
	Reclassification adjustment for amortization of actuarial loss and prior	(1		)	—			(1		)	5			2			3
	service cost, net, included in net income
	Effect on other comprehensive income	(1		)	—			(1		)	5			2			3
	Accumulated unrealized losses, net, for pension obligations,	$	(19	)	$	(6	)	$	(13	)	$	(96	)	$	(33	)	$	(63	)
	end of period
	Accumulated unrealized losses, net, on life deferred acquisition costs,	$	(16	)	$	(5	)	$	(11	)	$	(50	)	$	(17	)	$	(33	)
	life policy reserves and other, beginning of period
	Other comprehensive income before reclassification	1			1			—			27			10			17
	Reclassification adjustment for life deferred acquisition costs,	(1		)	(1		)	—			(3		)	(2		)	(1		)
	life policy reserves and other, net, included in net income
	Effect on other comprehensive income	—			—			—			24			8			16
	Accumulated unrealized losses, net, on life deferred acquisition costs,	$	(16	)	$	(5	)	$	(11	)	$	(26	)	$	(9	)	$	(17	)
	life policy reserves and other, end of period
	Accumulated other comprehensive income, beginning of period	$	2,301		$	797		$	1,504		$	1,724		$	595		$	1,129
	Change in unrealized gains, net, on investments available for sale	352			123			229			112			39			73
Change in pension obligations	(1		)	—			(1		)	5			2			3
Change in life deferred acquisition costs, life policy reserves	—			—			—			24			8			16
and other
Effect on other comprehensive income	351			123			228			141			49			92
Accumulated other comprehensive income, end of period	$	2,652		$	920		$	1,732		$	1,865		$	644		$	1,221

Reinsurance_Tables

Reinsurance (Tables)	6 Months Ended
	Jun. 30, 2014
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:
	(In millions)	Three months ended June 30,						Six months ended June 30,
		2014			2013			2014			2013
	Direct earned premiums	$	1,048		$	958		$	2,067		$	1,893
	Assumed earned premiums	2			3			5			5
	Ceded earned premiums	(44		)	(51		)	(87		)	(99		)
	Net earned premiums	$	1,006		$	910		$	1,985		$	1,799
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:
	(In millions)	Three months ended June 30,						Six months ended June 30,
		2014			2013			2014			2013
	Direct incurred loss and loss expenses	$	716		$	593		$	1,393		$	1,128
	Assumed incurred loss and loss expenses	2			5			4			7
	Ceded incurred loss and loss expenses	(11		)	(15		)	(14		)	(28		)
	Net incurred loss and loss expenses	$	707		$	583		$	1,383		$	1,107
Earned Life Insurance Premiums On Ceded Business	'
	Our condensed consolidated statements of income include earned life insurance premiums on ceded business:
	(In millions)	Three months ended June 30,						Six months ended June 30,
		2014			2013			2014			2013
	Direct earned premiums	$	68		$	58		$	130		$	114
	Ceded earned premiums	(15		)	(14		)	(29		)	(28		)
	Net earned premiums	$	53		$	44		$	101		$	86
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:
	(In millions)	Three months ended June 30,						Six months ended June 30,
		2014			2013			2014			2013
	Direct contract holders' benefits incurred	$	68		$	62		$	148		$	126
	Ceded contract holders' benefits incurred	(12		)	(14		)	(36		)	(34		)
	Net contract holders' benefits incurred	$	56		$	48		$	112		$	92

Income_Taxes_Tables

Income Taxes (Tables)	6 Months Ended
	Jun. 30, 2014
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 income tax rate and our effective income tax rate were as follows:
	(In millions)	Three months ended June 30,										Six months ended June 30,
		2014					2013					2014					2013
	Tax at statutory rate	$	37		35	%	$	52		35	%	$	79		35	%	$	128		35	%
	Increase (decrease) resulting from:
	Tax-exempt income from municipal bonds	(8		)	(7.5	)	(9		)	(6.1	)	(16		)	(7.1	)	(16		)	(4.4	)
	Dividend received exclusion	(7		)	(6.5	)	(6		)	(4.2	)	(14		)	(6.2	)	(12		)	(3.3	)
	Other	1			0.5		1			1		2			0.9		1			0.4
	Provision for income taxes	$	23		21.5	%	$	38		25.7	%	$	51		22.6	%	$	101		27.7	%

Net_Income_Per_Common_Share_Ta

Net Income Per Common Share (Tables)	6 Months Ended
	Jun. 30, 2014
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 June 30,				Six months ended June 30,
		2014		2013		2014		2013
	Numerator:
	Net income—basic and diluted	$	84	$	110	$	175	$	264
	Denominator:
	Basic weighted-average common shares outstanding	163.5		163.5		163.5		163.3
	Effect of stock-based awards:
	Stock options	1		1.2		1		1.1
	Nonvested shares	0.6		0.7		0.6		0.7
	Adjusted diluted weighted-average shares	165.1		165.4		165.1		165.2
	Earnings per share:
	Basic	$	0.51	$	0.67	$	1.07	$	1.62
	Diluted	0.51		0.66		1.06		1.6
	Number of anti-dilutive share-based awards	0.7		0.3		0.7		0.4

Employee_Retirement_Benefits_T

Employee Retirement Benefits (Tables)	6 Months Ended
	Jun. 30, 2014
Compensation and Retirement Disclosure [Abstract]	'
Schedule of Defined Benefit Plans Disclosures	'
	The following summarizes the components of net periodic costs for our qualified and supplemental pension plans:
	(In millions)	Three months ended June 30,						Six months ended June 30,
		2014			2013			2014			2013
	Service cost	$	3		$	3		$	5		$	6
	Interest cost	3			3			7			6
	Expected return on plan assets	(4		)	(4		)	(8		)	(8		)
	Amortization of actuarial loss and prior service cost	0			3			1			5
	Net periodic benefit cost	$	2		$	5		$	5		$	9

Segment_Information_Tables

Segment Information (Tables)	6 Months Ended
	Jun. 30, 2014
Segment Reporting [Abstract]	'
Segment Information	'
	Segment information is summarized in the following table:
	(In millions)	Three months ended June 30,						Six months ended June 30,
		2014			2013			2014			2013
	Revenues:
	Commercial lines insurance
	Commercial casualty	$	234		$	211		$	458		$	415
	Commercial property	180			152			351			299
	Commercial auto	132			117			258			231
	Workers' compensation	95			87			187			175
	Specialty packages	30			37			66			76
	Management liability and surety	31			30			62			59
	Machinery and equipment	12			11			24			21
	Commercial lines insurance premiums	714			645			1,406			1,276
	Fee revenue	1			1			2			1
	Total commercial lines insurance	715			646			1,408			1,277
	Personal lines insurance
	Personal auto	117			109			233			216
	Homeowner	111			99			220			195
	Other personal lines	30			29			59			57
	Personal lines insurance premiums	258			237			512			468
	Fee revenue	1			1			1			1
	Total personal lines insurance	259			238			513			469
	Excess and surplus lines insurance	34			28			67			55
	Life insurance premiums	53			44			101			86
	Separate account investment management fees	1			1			3			2
	Total life insurance	54			45			104			88
	Investment operations
	Investment income, net of expenses	136			131			271			259
	Realized investment gains, net	14			14			36			55
	Total investments	150			145			307			314
	Other	2			2			4			4
	Total revenues	$	1,214		$	1,104		$	2,403		$	2,207
	Income (loss) before income taxes:
	Insurance underwriting results
	Commercial lines insurance	$	28		$	34		$	30		$	92
	Personal lines insurance	(40		)	(1		)	(47		)	19
	Excess and surplus lines insurance	5			1			9			1
	Life insurance	(1		)	3			(1		)	10
	Investment operations	130			127			266			275
	Other	(15		)	(16		)	(31		)	(32		)
	Total income before income taxes	$	107		$	148		$	226		$	365
	Identifiable assets:	June 30,			December 31, 2013
		2014
	Property casualty insurance	$	2,636		$	2,455
	Life insurance	1,263			1,225
	Investment operations	14,104			13,618
	Other	332			364
	Total	$	18,335		$	17,662

Investments_Analysis_of_Cost_o

Investments - Analysis of Cost or Amortized Cost, Gross Unrealized Gains and Losses and Fair Value for Investments (Detail) (USD $)	Jun. 30, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Debt Securities	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Cost or Amortized Cost	$8,719	$8,638
Gross Unrealized Gains	686	558
Gross Unrealized Losses	22	75
Fair Value	9,383	9,121
Debt Securities | States, Municipalities And Political Subdivisions	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Cost or Amortized Cost	3,205	3,107
Gross Unrealized Gains	170	125
Gross Unrealized Losses	5	21
Fair Value	3,370	3,211
Debt Securities | Convertibles And Bonds With Warrants Attached	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Cost or Amortized Cost	7	17
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	7	17
Debt Securities | United States Government	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Cost or Amortized Cost	7	7
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	7	7
Debt Securities | Government-Sponsored Enterprises	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Cost or Amortized Cost	221	227
Gross Unrealized Gains	0	0
Gross Unrealized Losses	13	27
Fair Value	208	200
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 | Commercial Mortgage Backed Securities	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Cost or Amortized Cost	220	148
Gross Unrealized Gains	7	0
Gross Unrealized Losses	1	5
Fair Value	226	143
Debt Securities | Corporate Securities	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Cost or Amortized Cost	5,049	5,122
Gross Unrealized Gains	509	433
Gross Unrealized Losses	3	22
Fair Value	5,555	5,533
Equity Securities	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Cost or Amortized Cost	2,582	2,523
Gross Unrealized Gains	2,027	1,856
Gross Unrealized Losses	4	4
Fair Value	4,605	4,375
Equity Securities | Common Stock	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Cost or Amortized Cost	2,458	2,396
Gross Unrealized Gains	1,992	1,818
Gross Unrealized Losses	3	1
Fair Value	4,447	4,213
Equity Securities | Preferred Stock	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Cost or Amortized Cost	124	127
Gross Unrealized Gains	35	38
Gross Unrealized Losses	1	3
Fair Value	158	162
Fixed Maturities And Equity Securities	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Cost or Amortized Cost	11,301	11,161
Gross Unrealized Gains	2,713	2,414
Gross Unrealized Losses	26	79
Fair Value	$13,988	$13,496

Investments_Fair_Values_and_Un

Investments - Fair Values and Unrealized Losses by Investment Category and by Duration of Securities' Continuous Unrealized Loss Position (Detail) (USD $)	Jun. 30, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Investments, Unrealized Loss Position [Line Items]	'	'
Less than 12 months Fair Value	$164	$1,516
Less than 12 months Unrealized Losses	1	74
12 months or more Fair Value	708	86
12 months or more Unrealized Losses	25	5
Total Fair Value	872	1,602
Total Unrealized Losses	26	79
Fixed Maturities	'	'
Investments, Unrealized Loss Position [Line Items]	'	'
Less than 12 months Fair Value	120	1,397
Less than 12 months Unrealized Losses	1	70
12 months or more Fair Value	612	86
12 months or more Unrealized Losses	21	5
Total Fair Value	732	1,483
Total Unrealized Losses	22	75
Fixed Maturities | States, Municipalities And Political Subdivisions	'	'
Investments, Unrealized Loss Position [Line Items]	'	'
Less than 12 months Fair Value	61	490
Less than 12 months Unrealized Losses	1	18
12 months or more Fair Value	267	42
12 months or more Unrealized Losses	4	3
Total Fair Value	328	532
Total Unrealized Losses	5	21
Fixed Maturities | United States Government	'	'
Investments, Unrealized Loss Position [Line Items]	'	'
Less than 12 months Fair Value	0	1
Less than 12 months Unrealized Losses	0	0
12 months or more Fair Value	1	0
12 months or more Unrealized Losses	0	0
Total Fair Value	1	1
Total Unrealized Losses	0	0
Fixed Maturities | Government-Sponsored Enterprises	'	'
Investments, Unrealized Loss Position [Line Items]	'	'
Less than 12 months Fair Value	10	199
Less than 12 months Unrealized Losses	0	27
12 months or more Fair Value	175	1
12 months or more Unrealized Losses	13	0
Total Fair Value	185	200
Total Unrealized Losses	13	27
Fixed Maturities | Foreign Government Debt Securities [Member]	'	'
Investments, Unrealized Loss Position [Line Items]	'	'
Less than 12 months Fair Value	0	10
Less than 12 months Unrealized Losses	0	0
12 months or more Fair Value	10	0
12 months or more Unrealized Losses	0	0
Total Fair Value	10	10
Total Unrealized Losses	0	0
Fixed Maturities | Commercial Mortgage Backed Securities	'	'
Investments, Unrealized Loss Position [Line Items]	'	'
Less than 12 months Fair Value	0	125
Less than 12 months Unrealized Losses	0	5
12 months or more Fair Value	32	0
12 months or more Unrealized Losses	1	0
Total Fair Value	32	125
Total Unrealized Losses	1	5
Fixed Maturities | Corporate Securities	'	'
Investments, Unrealized Loss Position [Line Items]	'	'
Less than 12 months Fair Value	49	572
Less than 12 months Unrealized Losses	0	20
12 months or more Fair Value	127	43
12 months or more Unrealized Losses	3	2
Total Fair Value	176	615
Total Unrealized Losses	3	22
Equity Securities	'	'
Investments, Unrealized Loss Position [Line Items]	'	'
Less than 12 months Fair Value	44	119
Less than 12 months Unrealized Losses	0	4
12 months or more Fair Value	96	0
12 months or more Unrealized Losses	4	0
Total Fair Value	140	119
Total Unrealized Losses	4	4
Equity Securities | Common Stock	'	'
Investments, Unrealized Loss Position [Line Items]	'	'
Less than 12 months Fair Value	39	77
Less than 12 months Unrealized Losses	0	1
12 months or more Fair Value	79	0
12 months or more Unrealized Losses	3	0
Total Fair Value	118	77
Total Unrealized Losses	3	1
Equity Securities | Preferred Stock	'	'
Investments, Unrealized Loss Position [Line Items]	'	'
Less than 12 months Fair Value	5	42
Less than 12 months Unrealized Losses	0	3
12 months or more Fair Value	17	0
12 months or more Unrealized Losses	1	0
Total Fair Value	22	42
Total Unrealized Losses	$1	$3

Investments_Realized_Investmen

Investments - Realized Investment Gains and Losses and Change in Unrealized Investment Gains and Losses and Other Items (Detail) (USD $)	3 Months Ended		6 Months Ended
In Millions, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Investment income summary:	'	'	'	'
Interest on fixed maturities	$103	$103	$207	$205
Dividends on equity securities	34	30	66	57
Other investment income	1	0	2	1
Total	138	133	275	263
Less investment expenses	2	2	4	4
Total	136	131	271	259
Realized investment gains and losses summary:	'	'	'	'
Other	6	-2	8	-5
Realized gains on investments	14	14	36	55
Change in unrealized gains and losses summary:	'	'	'	'
Unrealized gains (losses) on investments available-for-sale	153	-159	229	73
Adjustment to deferred acquisition costs and life policy reserves	-5	26	-8	29
Amortization of pension actuarial loss and prior service cost	0	3	-1	5
Other	6	-2	8	-5
Income taxes on above	-82	76	123	49
Other comprehensive income (loss), net of tax	154	-141	228	92
Fixed Maturities	'	'	'	'
Realized investment gains and losses summary:	'	'	'	'
Gross realized gains	4	2	6	4
Gross realized losses	0	0	0	0
Other-than-temporary impairments	0	0	0	-2
Change in unrealized gains and losses summary:	'	'	'	'
Unrealized gains (losses) on investments available-for-sale	93	-282	181	-307
Equity Securities	'	'	'	'
Realized investment gains and losses summary:	'	'	'	'
Gross realized gains	16	12	34	49
Gross realized losses	0	0	0	0
Other-than-temporary impairments	0	0	-1	0
Securities with embedded derivatives	-3	0	-4	1
Other	-3	0	1	3
Realized gains on investments	14	14	'	'
Change in unrealized gains and losses summary:	'	'	'	'
Unrealized gains (losses) on investments available-for-sale	142	38	171	419
Other	($3)	$0	$1	$3

Investments_Additional_Informa

Investments - Additional Information (Detail) (USD $)	6 Months Ended	12 Months Ended	3 Months Ended	6 Months Ended			3 Months Ended	6 Months Ended
In Millions, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013	Jun. 30, 2014	Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013	Jun. 30, 2014	Jun. 30, 2014	Dec. 31, 2013	Jun. 30, 2014	Jun. 30, 2014
			Fixed Maturities	Fixed Maturities	Fixed Maturities	Fixed Maturities	Equity Securities	Equity Securities	Equity Securities	Procter And Gamble Company, Exxon Mobile Corporation And Chevron Corporation [Member]	Common Stock
			security	security	security	security	security	security
Gain (Loss) on Investments [Line Items]	'	'	'	'	'	'	'	'	'	'	'
Number Of Securities Other Than Temporary Impairment Losses1	'	'	0	1	7	'	1	3	'	'	'
Number Of Securities Continuous Unrealized Loss Position More Than Twelve Months	'	'	247	247	'	40	4	4	'	'	'
Number of securities	'	'	'	'	'	'	'	'	'	'	7
Unrealized investment gains due to a net gain position	'	'	$686	$686	'	$558	$2,027	$2,027	$1,856	$599	'
Fixed maturities, fair value of hybrid securities	7	18	'	'	'	'	'	'	'	'	'
Unrealized losses 12 months or more (equity investment less than $500,000)	$25	$5	$21	$21	'	$5	$4	$4	$0	'	'
Fixed maturity investments, Percentage of amortized costs	70.00%	70.00%	'	'	'	'	'	'	'	'	'

Fair_Value_Measurements_Fair_V

Fair Value Measurements - Fair Value Hierarchy for Assets Measured at Fair Value on Recurring Basis (Detail) (USD $)	Jun. 30, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fixed maturities, at fair value	$9,383	$9,121
Equity securities, at fair value	4,605	4,375
Separate accounts	731	692
Fair value of asset	14,724	14,192
Top Hat Savings Plan	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Other investments	17	14
Debt Securities	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fixed maturities, at fair value	9,383	9,121
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	3,370	3,211
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	7	17
Debt Securities | United States Government	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fixed maturities, at fair value	7	7
Debt Securities | Government-Sponsored Enterprises	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fixed maturities, at fair value	208	200
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 | Commercial Mortgage Backed Securities	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fixed maturities, at fair value	226	143
Debt Securities | Corporate Securities	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fixed maturities, at fair value	5,555	5,533
Equity Securities | Common Stock	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Equity securities, at fair value	4,447	4,213
Equity Securities | Preferred Stock	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Equity securities, at fair value	158	162
Taxable Fixed Maturities	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Separate accounts	719	682
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	4,471	4,234
Quoted prices in active markets for identical assets (Level 1) | Top Hat Savings Plan	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Other investments	17	14
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	7	7
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 | 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	7	7
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 | Commercial Mortgage Backed Securities	'	'
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 | Corporate Securities	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fixed maturities, at fair value	0	0
Quoted prices in active markets for identical assets (Level 1) | Equity Securities | Common Stock	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Equity securities, at fair value	4,447	4,213
Quoted prices in active markets for identical assets (Level 1) | Equity Securities | Preferred Stock	'	'
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	10,242	9,954
Significant other observable inputs (Level 2) | Top Hat Savings Plan	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Other investments	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	9,367	9,112
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	3,370	3,211
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	7	17
Significant other observable inputs (Level 2) | Debt Securities | United States Government	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fixed maturities, at fair value	0	0
Significant other observable inputs (Level 2) | Debt Securities | Government-Sponsored Enterprises	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fixed maturities, at fair value	208	200
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 | Commercial Mortgage Backed Securities	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fixed maturities, at fair value	226	143
Significant other observable inputs (Level 2) | Debt Securities | Corporate Securities	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fixed maturities, at fair value	5,546	5,531
Significant other observable inputs (Level 2) | Equity Securities | Common Stock	'	'
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 | Preferred Stock	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Equity securities, at fair value	156	160
Significant other observable inputs (Level 2) | Taxable Fixed Maturities	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Separate accounts	719	682
Significant unobservable inputs (Level 3)	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair value of asset	11	4
Significant unobservable inputs (Level 3) | Top Hat Savings Plan	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Other investments	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	9	2
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 | 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) | 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 | Commercial Mortgage Backed Securities	'	'
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 | Corporate Securities	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fixed maturities, at fair value	9	2
Significant unobservable inputs (Level 3) | Equity Securities | Common Stock	'	'
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 | Preferred Stock	'	'
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_Change

Fair Value Measurements - Change in Level 3 Assets (Detail) (USD $)	3 Months Ended		6 Months Ended
In Millions, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'	'	'	'
Beginning balance	$15	$6	$4	$5
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	1
Sales	0	0	0	0
Transfers into Level 3	1	0	12	0
Transfers out of Level 3	-5	0	-5	0
Ending balance	11	6	11	6
Corporate Fixed Maturities	'	'	'	'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'	'	'	'
Beginning balance	8	3	2	3
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	1	0	7	0
Transfers out of Level 3	0	0	0	0
Ending balance	9	3	9	3
Commercial Mortgage Backed Securities	'	'	'	'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'	'	'	'
Beginning balance	5	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	5	0
Transfers out of Level 3	-5	0	-5	0
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	0	1	0	1
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	0	1	0	1
Preferred Equities	'	'	'	'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'	'	'	'
Beginning balance	2	2	2	1
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	1
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_Summar

Fair Value Measurements - Summary of Book Value and Principal Amounts of Long-Term Debt (Detail) (USD $)	6 Months Ended	12 Months Ended
In Millions, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Debt Instrument [Line Items]	'	'
Book value	$790	$790
Principal amount of debt	793	793
Senior Debentures 6.900% Due 2028	'	'
Debt Instrument [Line Items]	'	'
Interest rate	6.90%	6.90%
Debt issuance year	'1998	'1998
Book value	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	'2005	'2005
Book value	391	391
Principal amount of debt	391	391
Senior Notes 6.152% Due 2034	'	'
Debt Instrument [Line Items]	'	'
Interest rate	6.13%	6.13%
Debt issuance year	'2004	'2004
Book value	371	371
Principal amount of debt	$374	$374

Fair_Value_Measurements_Fair_V1

Fair Value Measurements - Fair Values of Note Payable and Long-Term Debt (Detail) (USD $)	6 Months Ended	12 Months Ended
In Millions, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair value of note payable	$49	$104
Total	1,000	991
Senior Debentures 6.900 % Due 2028	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Interest rate	6.90%	6.90%
Debt instrument, year of maturity	'2028	'2028
Fair value of senior debt	34	30
Senior Debentures 6.920 % Due 2028	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Interest rate	6.92%	6.92%
Debt instrument, year of maturity	'2028	'2028
Fair value of senior debt	485	458
Senior Notes 6.125 % Due 2034	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Interest rate	6.13%	6.13%
Debt instrument, year of maturity	'2034	'2034
Fair value of senior debt	432	399
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	49	104
Total	1,000	991
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	30
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	485	458
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	432	399
Significant unobservable inputs (Level 3)	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair value of note payable	0	0
Total	0	0
Significant unobservable inputs (Level 3) | Senior Debentures 6.900 % Due 2028	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair value of senior debt	0	0
Significant unobservable inputs (Level 3) | Senior Debentures 6.920 % Due 2028	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair value of senior debt	0	0
Significant unobservable inputs (Level 3) | Senior Notes 6.125 % Due 2034	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair value of senior debt	$0	$0

Fair_Value_Measurements_Fair_V2

Fair Value Measurements - Fair Value of Life Policy Loans (Detail) (USD $)	Jun. 30, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair value of life policy loans	$43	$45
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	$43	$45

Fair_Value_Measurements_Fair_V3

Fair Value Measurements - Fair Values of Deferred Annuities, Structured Settlements and Other Items (Detail) (USD $)	Jun. 30, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair Value of life insurance liabilities	$1,129	$1,130
Deferred Annuities	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair Value of life insurance liabilities	911	911
Structured Settlements	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair Value of life insurance liabilities	218	219
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	218	219
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	218	219
Significant unobservable inputs (Level 3)	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair Value of life insurance liabilities	911	911
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	911	911
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_Additi

Fair Value Measurements - Additional Information (Detail) (USD $)	3 Months Ended	6 Months Ended
In Millions, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'	'
Repayments of Notes Payable	$55	$55	$0	'
Finance receivable	80	80	'	85
Loss and loss expense reserves	4,444	4,444	'	4,311
Maximum	'	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'	'
Percentage of Level 3 assets measured at fair value	1.00%	1.00%	'	'
Life Policy Loans	'	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'	'
Finance receivable	34	34	'	36
Deferred Annuities And Structured Settlements	'	'	'	'
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	865	865	'	862
Loss and loss expense reserves	$184	$184	'	$189

Property_Casualty_Loss_and_Los2

Property Casualty Loss and Loss Expenses - Consolidated Property Casualty Loss and Loss Expense Reserves (Detail) (USD $)	3 Months Ended		6 Months Ended
In Millions, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Summary of Consolidated Property Casualty Loss and Loss Expense Reserves [Roll Forward]	'	'	'	'
Gross loss and loss expense reserves, beginning of period	$4,323	$4,173	$4,241	$4,169
Less reinsurance receivable	289	349	299	356
Net loss and loss expense reserves, beginning of period	4,034	3,824	3,942	3,813
Current accident year	773	675	1,478	1,209
Prior accident years	-66	-92	-95	-102
Total incurred	707	583	1,383	1,107
Current accident year	309	249	506	370
Prior accident years	306	272	693	664
Total paid	615	521	1,199	1,034
Net loss and loss expense reserves, end of period	4,126	3,886	4,126	3,886
Plus reinsurance receivable	282	333	282	333
Gross loss and loss expense reserves, end of period	$4,408	$4,219	$4,408	$4,219

Property_Casualty_Loss_and_Los3

Property Casualty Loss and Loss Expenses - Additional Information (Detail) (USD $)	3 Months Ended		6 Months Ended
In Millions, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Supplemental Information for Property, Casualty Insurance Underwriters [Line Items]	'	'	'	'
Favorable reserve development on prior accident years	$66	$92	$95	$102
Life and Health Loss Reserves	'	'	'	'
Supplemental Information for Property, Casualty Insurance Underwriters [Line Items]	'	'	'	'
Reserve for loss and loss expenses	36	65	36	65
Commercial Lines	'	'	'	'
Supplemental Information for Property, Casualty Insurance Underwriters [Line Items]	'	'	'	'
Favorable reserve development on prior accident years	57	'	60	'
Commercial Lines | Commerical Casualty Business [Member]	'	'	'	'
Supplemental Information for Property, Casualty Insurance Underwriters [Line Items]	'	'	'	'
Favorable reserve development on prior accident years	24	'	'	'
Commercial Lines | Commercial Property Segment [Member]	'	'	'	'
Supplemental Information for Property, Casualty Insurance Underwriters [Line Items]	'	'	'	'
Favorable reserve development on prior accident years	22	'	24	'
Commercial Lines | Workers Compensation [Member]	'	'	'	'
Supplemental Information for Property, Casualty Insurance Underwriters [Line Items]	'	'	'	'
Favorable reserve development on prior accident years	'	'	30	'
Personal Lines	'	'	'	'
Supplemental Information for Property, Casualty Insurance Underwriters [Line Items]	'	'	'	'
Favorable reserve development on prior accident years	1	'	18	'
Excess And Surplus Lines Insurance	'	'	'	'
Supplemental Information for Property, Casualty Insurance Underwriters [Line Items]	'	'	'	'
Favorable reserve development on prior accident years	8	'	17	'
Consolidated Property and Casualty Insurance Entity [Member] | Catastrophe Development	'	'	'	'
Supplemental Information for Property, Casualty Insurance Underwriters [Line Items]	'	'	'	'
Favorable reserve development on prior accident years	$5	$8	$14	$15

Reserves_in_Addition_to_Accoun

Reserves in Addition to Account Balance, Based on Expected No-Lapse Guarantee Benefits and Expected Policy Assessments (Detail) (USD $)	Jun. 30, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Liability for Future Policy Benefit, by Product Segment [Line Items]	'	'
Life policy and investment contract reserves	$2,454	$2,390
Ordinary/Traditional Life	'	'
Liability for Future Policy Benefit, by Product Segment [Line Items]	'	'
Life policy and investment contract reserves	848	815
Universal Life	'	'
Liability for Future Policy Benefit, by Product Segment [Line Items]	'	'
Life policy and investment contract reserves	511	508
Deferred Annuities	'	'
Liability for Future Policy Benefit, by Product Segment [Line Items]	'	'
Life policy and investment contract reserves	865	862
Structured Settlements	'	'
Liability for Future Policy Benefit, by Product Segment [Line Items]	'	'
Life policy and investment contract reserves	184	189
Other	'	'
Liability for Future Policy Benefit, by Product Segment [Line Items]	'	'
Life policy and investment contract reserves	$46	$16

Deferred_Acquisition_Costs_Def

Deferred Acquisition Costs - Deferred Policy Acquisition Costs and Asset Reconciliation (Detail) (USD $)	3 Months Ended		6 Months Ended
In Millions, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Movement Analysis of Deferred Policy Acquisition Costs [Roll Forward]	'	'	'	'
Deferred policy acquisition costs asset, beginning of period	$564	$491	$565	$470
Capitalized deferred policy acquisition costs	216	203	422	401
Amortized deferred policy acquisition costs	-202	-183	-403	-362
Amortized shadow deferred policy acquisition costs	-7	35	-13	37
Deferred policy acquisition costs asset, end of period	$571	$546	$571	$546

Accumulated_Other_Comprehensiv2

Accumulated Other Comprehensive Income (Details) (USD $)	3 Months Ended		6 Months Ended
In Millions, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Mar. 31, 2014	Dec. 31, 2013	Mar. 31, 2013	Dec. 31, 2012
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]	'	'	'	'	'	'	'	'
Accumulated other comprehensive income, net of tax, beginning of period	$1,732	'	$1,732	'	'	$1,504	'	'
Accumulated other comprehensive income, net of tax, end of period	1,732	'	1,732	'	'	1,504	'	'
Accumulated Net Unrealized Investment Gain (Loss)	'	'	'	'	'	'	'	'
Accumulated Other Comprehensive Income Loss Before Tax [Abstract]	'	'	'	'	'	'	'	'
Accumulated unrealized gains, net, on investments available for sale, before tax, beginning of period	2,452	2,231	2,335	1,875	'	'	'	'
Other comprehensive income before reclassification, before tax	252	-230	387	164	'	'	'	'
Reclassification adjustment for realized gains, net, included in net income, before tax	-17	-14	-35	-52	'	'	'	'
Effect on other comprehensive income, before tax	235	-244	352	112	'	'	'	'
Accumulated unrealized gains, net, on investments available for sale, before tax, end of period	2,687	1,987	2,687	1,987	'	'	'	'
Accumulated Other Comprehensive Income Loss Tax [Abstract]	'	'	'	'	'	'	'	'
Accumulated unrealized gains, net, on investments available for sale and other invested assets, tax, beginning of period	931	686	931	686	'	'	'	'
Other comprehensive income before reclassification, tax	87	-81	135	56	'	'	'	'
Reclassification adjustment for realized gains, net, included in net income, tax	-5	-4	-12	-17	'	'	'	'
Effect on other comprehensive income, tax	82	-85	123	39	'	'	'	'
Accumulated unrealized gains, net, on investments available for sale and other invested assets, tax, end of period	849	771	808	647	'	'	'	'
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]	'	'	'	'	'	'	'	'
Accumulated unrealized gains, net, on investments available for sale and other invested assets, net of tax, beginning of period	1,603	1,460	1,527	1,228	'	'	'	'
Other comprehensive income before reclassification , net of tax	165	-149	252	108	'	'	'	'
Reclassification adjustment for realized gains, net, included in net income, net of tax	-12	-10	-23	-35	'	'	'	'
Effect on other comprehensive income, net of tax	153	-159	229	73	'	'	'	'
Accumulated unrealized gains, net, on investments available for sale and other invested assets, net of tax, end of period	1,756	1,301	1,756	1,301	'	'	'	'
Accumulated Defined Benefit Plans Adjustment	'	'	'	'	'	'	'	'
Accumulated Other Comprehensive Income Loss Before Tax [Abstract]	'	'	'	'	'	'	'	'
Other comprehensive income before reclassification, before tax	0	'	0	0	'	'	'	'
Accumulated unrealized losses, net, for pension obligations, before Tax, beginning of period	-19	-99	-18	-101	'	'	'	'
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Amortization of Actuarial Gain (Loss) and Prior Service Cost, before Tax	0	3	-1	5	'	'	'	'
Effect on other comprehensive income, before tax	0	3	-1	5	'	'	'	'
Accumulated unrealized losses, net, for pension obligations, before Tax, end of period	-19	-96	-19	-96	'	'	'	'
Accumulated Other Comprehensive Income Loss Tax [Abstract]	'	'	'	'	'	'	'	'
Other comprehensive income before reclassification, tax	0	0	0	0	'	'	'	'
Accumulated unrealized losses, net, for pension obligations, tax, beginning of period	-6	-34	-6	-35	'	'	'	'
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Amortization of Actuarial Gain (Loss) and Prior Service Cost, Tax	0	1	0	2	'	'	'	'
Effect on other comprehensive income, tax	0	1	0	2	'	'	'	'
Accumulated unrealized losses, net, for pension obligations, tax, end of period	-6	-33	-6	-33	'	'	'	'
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]	'	'	'	'	'	'	'	'
Other comprehensive income before reclassification , net of tax	0	0	0	0	'	'	'	'
Accumulated unrealized losses, net, for pension obligations, net of tax, beginning of period	-13	-65	-12	-66	'	'	'	'
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Amortization of Actuarial Gain (Loss) and Prior Service Cost, Net of Tax	0	2	-1	3	'	'	'	'
Effect on other comprehensive income, net of tax	0	2	-1	3	'	'	'	'
Accumulated unrealized losses, net, for pension obligations, net of tax, end of period	-13	-63	-13	-63	'	'	'	'
Accumulated Net Unrealized Gain (Loss) on Deferred Costs, Reserves And Other	'	'	'	'	'	'	'	'
Accumulated Other Comprehensive Income Loss Before Tax [Abstract]	'	'	'	'	'	'	'	'
Other comprehensive income before reclassification, before tax	-2	27	1	27	'	'	'	'
Accumulated unrealized losses, net, on life deferred acquisition costs, life policy reserves and other, before tax, beginning of period	-17	-50	-16	-50	'	'	'	'
Other Comprehensive Income (Loss), Reclassification Adjustment for Life Deferred Acquisition Costs, Life Policy Reserves and Other, Before Tax	3	-3	-1	-3	'	'	'	'
Effect on other comprehensive income, before tax	1	24	0	24	'	'	'	'
Accumulated unrealized losses, net, on life deferred acquisition costs, life policy reserves and other, before tax, end of period	-16	-26	-16	-26	'	'	'	'
Accumulated Other Comprehensive Income Loss Tax [Abstract]	'	'	'	'	'	'	'	'
Other comprehensive income before reclassification, tax	0	10	1	10	'	'	'	'
Accumulated unrealized losses, net, on life deferred acquisition costs, life policy reserves and other, tax, beginning of period	-5	-17	-5	-17	'	'	'	'
Other Comprehensive Income (Loss), Reclassification Adjustment for Life Deferred Acquisition Costs, Life Policy Reserves and Other, Tax	0	-2	-1	-2	'	'	'	'
Effect on other comprehensive income, tax	0	8	0	8	'	'	'	'
Accumulated unrealized losses, net, on life deferred acquisition costs, life policy reserves and other, tax, end of period	-5	-9	-5	-9	'	'	'	'
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]	'	'	'	'	'	'	'	'
Other comprehensive income before reclassification , net of tax	-2	17	0	17	'	'	'	'
Accumulated unrealized losses, net, on life deferred acquisition costs, life policy reserves and other, beginning of period, net of tax	-12	-33	-11	-33	'	'	'	'
Other Comprehensive Income (Loss), Reclassification Adjustment for Life Deferred Acquisition Costs, Life Policy Reserves and Other, Net of Tax	3	-1	0	-1	'	'	'	'
Effect on other comprehensive income, net of tax	1	16	0	16	'	'	'	'
Accumulated unrealized losses, net, on life deferred acquisition costs, life policy reserves and other, end of period, net of tax	-11	-17	-11	-17	'	'	'	'
Accumulated Other Comprehensive Income (Loss)	'	'	'	'	'	'	'	'
Accumulated Other Comprehensive Income Loss Before Tax [Abstract]	'	'	'	'	'	'	'	'
Accumulated other comprehensive income, before taxes, beginning of period	2,416	2,082	2,301	1,724	'	'	'	'
Change in unrealized gains, net, on investments available for sale, before Tax	235	-244	352	112	'	'	'	'
Change in pension obligations, before tax	0	3	-1	5	'	'	'	'
Change in life deferred acquisition costs, life policy reserves and other, before Tax	1	24	0	24	'	'	'	'
Effect on other comprehensive income, before Tax	236	-217	351	141	'	'	'	'
Accumulated other comprehensive income, before taxes, end of period	2,652	1,865	2,652	1,865	'	'	'	'
Accumulated Other Comprehensive Income Loss Tax [Abstract]	'	'	'	'	'	'	'	'
Accumulated other comprehensive income, tax, beginning of period	838	720	797	595	'	'	'	'
Change in unrealized gains, net, on investments available for sale and other invested assets, tax	82	-85	123	39	'	'	'	'
Change in pension obligations, tax	0	1	0	2	'	'	'	'
Change in life deferred acquisition costs, life policy reserves and other, tax	0	8	0	8	'	'	'	'
Effect on other comprehensive income, tax	82	-76	123	49	'	'	'	'
Accumulated other comprehensive income, tax, end of period	920	644	920	644	'	'	'	'
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]	'	'	'	'	'	'	'	'
Accumulated other comprehensive income, net of tax, beginning of period	1,732	1,221	1,732	1,221	1,578	1,504	1,362	1,129
Change in unrealized gains, net, on investments available for sale, net of tax	153	-159	229	73	'	'	'	'
Change in pension obligations, net of tax	0	2	-1	3	'	'	'	'
Change in life deferred acquisition costs, life policy reserves and other, net of tax	1	16	0	16	'	'	'	'
Effect on other comprehensive income, net of tax	154	-141	228	92	'	'	'	'
Accumulated other comprehensive income, net of tax, end of period	$1,732	$1,221	$1,732	$1,221	$1,578	$1,504	$1,362	$1,129

Reinsurance_Earned_Consolidate

Reinsurance - Earned Consolidated Property Casualty Insurance Premiums on Assumed and Ceded Business (Detail) (USD $)	3 Months Ended		6 Months Ended
In Millions, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Reinsurance Disclosures [Abstract]	'	'	'	'
Direct earned premiums	$1,048	$958	$2,067	$1,893
Assumed earned premiums	2	3	5	5
Ceded earned premiums	-44	-51	-87	-99
Net earned premiums	$1,006	$910	$1,985	$1,799

Reinsurance_Incurred_Consolida

Reinsurance - Incurred Consolidated Property Casualty Insurance Loss and Loss Expenses on Assumed and Ceded Business (Detail) (USD $)	3 Months Ended		6 Months Ended
In Millions, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]	'	'	'	'
Net incurred loss and loss expenses	$763	$631	$1,495	$1,199
Property, Liability And Casualty Insurance Segment	'	'	'	'
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]	'	'	'	'
Direct incurred loss and loss expenses	716	593	1,393	1,128
Assumed incurred loss and loss expenses	2	5	4	7
Ceded incurred loss and loss expenses	-11	-15	-14	-28
Net incurred loss and loss expenses	$707	$583	$1,383	$1,107

Reinsurance_Earned_Life_Insura

Reinsurance - Earned Life Insurance Premiums on Ceded Business (Detail) (USD $)	3 Months Ended		6 Months Ended
In Millions, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]	'	'	'	'
Direct earned premiums	$1,048	$958	$2,067	$1,893
Ceded earned premiums	-44	-51	-87	-99
Life Insurance Segment	'	'	'	'
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]	'	'	'	'
Direct earned premiums	68	58	130	114
Ceded earned premiums	-15	-14	-29	-28
Net earned premiums	$53	$44	$101	$86

Reinsurance_Life_Insurance_Con

Reinsurance - Life Insurance Contract Holders' Benefits Incurred on Ceded Business (Detail) (USD $)	3 Months Ended		6 Months Ended
In Millions, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]	'	'	'	'
Net incurred loss and loss expenses	$763	$631	$1,495	$1,199
Life Insurance Segment	'	'	'	'
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]	'	'	'	'
Direct contract holders' benefits incurred	68	62	148	126
Ceded contract holders' benefits incurred	-12	-14	-36	-34
Net incurred loss and loss expenses	$56	$48	$112	$92

Income_Taxes_Differences_Betwe

Income Taxes - Differences Between 35 Percent Statutory Income Tax Rate and Effective Income Tax Rate (Detail) (USD $)	3 Months Ended		6 Months Ended
In Millions, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Income Tax Disclosure [Abstract]	'	'	'	'
Tax at statutory rate	$37	$52	$79	$128
Increase (decrease) resulting from:	'	'	'	'
Tax-exempt income from municipal bonds	-8	-9	-16	-16
Dividend received exclusion	-7	-6	-14	-12
Other	1	1	2	1
Total provision for income taxes	$23	$38	$51	$101
Tax at statutory rate	35.00%	35.00%	35.00%	35.00%
Increase (decrease) resulting from:	'	'	'	'
Tax-exempt income from municipal bonds	-7.50%	-6.10%	-7.10%	-4.40%
Dividend received exclusion	-6.50%	-4.20%	-6.20%	-3.30%
Other	0.50%	1.00%	0.90%	0.40%
Provision for income taxes	21.50%	25.70%	22.60%	27.70%

Income_Taxes_Narrative_Details

Income Taxes (Narrative) (Details)	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Income Tax Disclosure [Abstract]	'	'	'	'
Tax at statutory rate, percentage	35.00%	35.00%	35.00%	35.00%

Net_Income_Per_Common_Share_Ca

Net Income Per Common Share - Calculations for Basic and Diluted Earnings Per Share (Detail) (USD $)	3 Months Ended		6 Months Ended
In Millions, except Per Share data, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Numerator:	'	'	'	'
Net income-basic and diluted	$84	$110	$175	$264
Denominator:	'	'	'	'
Weighted-average common shares outstanding (in shares)	163.5	163.5	163.5	163.3
Adjusted diluted weighted-average shares (in shares)	165.1	165.4	165.1	165.2
Earnings per share:	'	'	'	'
Basic (in USD per share)	$0.51	$0.67	$1.07	$1.62
Diluted (in USD per share)	$0.51	$0.66	$1.06	$1.60
Number of anti-dilutive stock-based awards (in shares)	0.7	0.3	0.7	0.4
Stock Options	'	'	'	'
Denominator:	'	'	'	'
Effect of stock-based awards (in shares)	1	1.2	1	1.1
Nonvested shares	'	'	'	'
Denominator:	'	'	'	'
Effect of stock-based awards (in shares)	0.6	0.7	0.6	0.7

Employee_Retirement_Benefits_C

Employee Retirement Benefits - Components of Net Periodic Costs for Qualified and Supplemental Pension Plans (Detail) (USD $)	3 Months Ended		6 Months Ended
In Millions, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Compensation and Retirement Disclosure [Abstract]	'	'	'	'
Service cost	$3	$3	$5	$6
Interest cost	3	3	7	6
Expected return on plan assets	-4	-4	-8	-8
Amortization of actuarial loss and prior service cost	0	3	1	5
Net periodic benefit cost	$2	$5	$5	$9

Employee_Retirement_Benefits_A

Employee Retirement Benefits - Additional Information (Detail) (USD $)	3 Months Ended		6 Months Ended		3 Months Ended
In Millions, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Mar. 31, 2014	Jun. 30, 2014
					Qualified Pension Plans [Member]	Qualified Pension Plans [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]	'	'	'	'	'	'
Matching contributions for 401(k) plan and Top Hat savings plan	$2	$2	$6	$5	'	'
Pension Contributions	'	'	'	'	5	'
Expected contribution by employer for the remainder of the year	'	'	'	'	'	$0

Commitments_and_Contingent_Lia1

Commitments and Contingent Liabilities (Narrative) (Details) (USD $)	6 Months Ended
In Millions, unless otherwise specified	Jun. 30, 2014
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 $)	3 Months Ended		6 Months Ended
In Millions, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013
Segment Reporting Information [Line Items]	'	'	'	'	'
Revenues	$1,214	$1,104	$2,403	$2,207	'
Net Investment Income	136	131	271	259	'
Realized gains on investments	14	14	36	55	'
Income (loss) before income taxes	107	148	226	365	'
Identifiable assets	18,335	'	18,335	'	17,662
Property Casualty Insurance Segment	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Identifiable assets	2,636	'	2,636	'	2,455
Commercial Lines	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Revenues	715	646	1,408	1,277	'
Income (loss) before income taxes	28	34	30	92	'
Commercial Lines | Commercial Casualty Segment	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Revenues	234	211	458	415	'
Commercial Lines | Commercial Property Segment	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Revenues	180	152	351	299	'
Commercial Lines | Commercial Auto Segment	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Revenues	132	117	258	231	'
Commercial Lines | Workers' Compensation	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Revenues	95	87	187	175	'
Commercial Lines | Specialty Packages	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Revenues	30	37	66	76	'
Commercial Lines | Management liability and surety	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Revenues	31	30	62	59	'
Commercial Lines | Machinery and Equipment	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Revenues	12	11	24	21	'
Commercial Lines | Commercial Lines Insurance Premiums	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Revenues	714	645	1,406	1,276	'
Commercial Lines | Other Fee Revenue	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Revenues	1	1	2	1	'
Personal Lines	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Revenues	259	238	513	469	'
Income (loss) before income taxes	-40	-1	-47	19	'
Personal Lines | Personal Auto	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Revenues	117	109	233	216	'
Personal Lines | Home Owner Segment	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Revenues	111	99	220	195	'
Personal Lines | Other Personal Lines	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Revenues	30	29	59	57	'
Personal Lines | Commercial Lines Insurance Premiums	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Revenues	258	237	512	468	'
Personal Lines | Other Fee Revenue	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Revenues	1	1	1	1	'
Excess And Surplus Lines Insurance	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Revenues	34	28	67	55	'
Income (loss) before income taxes	5	1	9	1	'
Life Insurance Segment	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Revenues	54	45	104	88	'
Income (loss) before income taxes	-1	3	-1	10	'
Identifiable assets	1,263	'	1,263	'	1,225
Life Insurance Segment | Life Insurance Excluding Account Investment Fees	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Revenues	53	44	101	86	'
Life Insurance Segment | Seperate Account Investment Management Fees	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Revenues	1	1	3	2	'
Investments Segment	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Revenues	150	145	307	314	'
Income (loss) before income taxes	130	127	266	275	'
Identifiable assets	14,104	'	14,104	'	13,618
Investments Segment | Investment Income, Net	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Net Investment Income	136	131	271	259	'
Investments Segment | Realized Investment Gains, Net	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Realized gains on investments	14	14	36	55	'
Other	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Revenues	2	2	4	4	'
Income (loss) before income taxes	-15	-16	-31	-32	'
Identifiable assets	$332	'	$332	'	$364

Segment_Information_Narrative_

Segment Information - Narrative (Details)	6 Months Ended
	Jun. 30, 2014
	segment
	industry
Segment Reporting [Abstract]	'
Number of Industries Operating In	2
Number of Reportable Segments	5