CNA Financial (CNA) 10-Q 3 May 16 2016 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information Document - shares	3 Months Ended
	Mar. 31, 2016	Apr. 29, 2016
Document and Entity Information [Abstract]
Entity Registrant Name	CNA FINANCIAL CORP
Entity Central Index Key	21,175
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Document Type	10-Q
Document Period End Date	Mar. 31, 2016
Document Fiscal Year Focus	2,016
Document Fiscal Period Focus	Q1
Amendment Flag	false
Entity Common Stock, Shares Outstanding		270,479,961

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($) shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Revenues
Net earned premiums	$ 1,699	$ 1,687
Net investment income	435	558
Net realized investment gains (losses):
Other-than-temporary impairment losses	(23)	(12)
Other net realized investment (losses) gains	(13)	22
Net realized investment gains (losses)	(36)	10
Other revenues	97	97
Total revenues	2,195	2,352
Claims, Benefits and Expenses
Insurance claims and policyholders' benefits	1,408	1,339
Amortization of deferred acquisition costs	307	303
Other operating expenses	381	358
Interest	42	39
Total claims, benefits and expenses	2,138	2,039
Income (loss) from continuing operations before income tax	57	313
Income tax benefit (expense)	9	(80)
Net income (Loss)	$ 66	$ 233
Earnings Per Share, Basic	$ 0.25	$ 0.86
Earnings Per Share, Diluted	0.24	0.86
Dividends declared per share	$ 2.25	$ 2.25
Weighted Average Outstanding Common Stock and Common Stock Equivalents
Basic	270.3	270.1
Diluted	270.9	270.7

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Statement of Comprehensive Income [Abstract]
Net Income (Loss)	$ 66	$ 233
Other Comprehensive Income (Loss), Net of Tax, Changes In:
Net unrealized gains (losses) on investments with other-than-temporary impairments	5	(1)
Net unrealized gains (losses) on other investments	234	112
Net unrealized gains (losses) on investments	239	111
Foreign currency translation adjustment	14	(96)
Pension and postretirement benefits	6	6
Other comprehensive income (loss), net of tax	259	21
Total comprehensive income (loss)	$ 325	$ 254

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Millions	Mar. 31, 2016	Dec. 31, 2015
Assets
Fixed maturity securities at fair value (amortized cost of $37,271 and $37,253)	$ 40,252	$ 39,572
Equity securities at fair value (cost of $182 and $191)	189	197
Limited partnership investments	2,562	2,548
Other invested assets	45	44
Mortgage loans	675	678
Short term investments	1,648	1,660
Total investments	45,371	44,699
Cash	242	387
Reinsurance receivables (less allowance for uncollectible receivables of $38 and $38)	4,692	4,453
Insurance receivables (less allowance for uncollectible receivables of $50 and $51)	2,151	2,078
Accrued investment income	426	404
Deferred acquisition costs	622	598
Deferred income taxes	461	638
Property and equipment at cost (less accumulated depreciation of $214 and $382)	263	343
Goodwill	150	150
Other assets (includes $66 and $0 due from Loews Corporation)	1,124	1,295
Total assets	55,502	55,045
Liabilities
Claim and claim adjustment expenses	23,018	22,663
Unearned premiums	3,807	3,671
Future policy benefits	10,500	10,152
Short term debt	0	350
Long term debt	2,708	2,210
Other liabilities (includes $7 and $82 due to Loews Corporation)	3,999	4,243
Total liabilities	44,032	43,289
Stockholders' Equity
Common stock ($2.50 par value; 500,000,000 shares authorized; 273,040,243 shares issued; 270,479,961 and 270,274,361 shares outstanding)	683	683
Additional paid-in capital	2,146	2,153
Retained earnings	8,770	9,313
Accumulated other comprehensive income (loss)	(56)	(315)
Treasury stock (2,560,282 and 2,765,882 shares), at cost	(73)	(78)
Total stockholders’ equity	11,470	11,756
Total liabilities and stockholders' equity	$ 55,502	$ 55,045

Consolidated Balance Sheet Pare

Consolidated Balance Sheet Parentheticals (Parentheticals) - USD ($) $ in Millions	Mar. 31, 2016	Dec. 31, 2015
Statement of Financial Position [Abstract]
Fixed maturities securities at amortized cost	$ 37,271	$ 37,253
Equity securities at cost	182	191
Allowance for uncollectible reinsurance receivables	38	38
Allowance for uncollectible insurance receivables	50	51
Accumulated depreciation on property and equipment	214	382
Due from Parent Company	66	0
Due to Parent Company	$ 7	$ 82
Common stock, par value	$ 2.50	$ 2.50
Common stock, shares authorized	500,000,000	500,000,000
Common stock, shares issued	273,040,243	273,040,243
Common stock, shares outstanding	270,479,961	270,274,361
Treasury stock, shares	2,560,282	2,765,882

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Cash Flows from Operating Activities
Net Income (Loss)	$ 66	$ 233
Adjustments to reconcile net income (loss) to net cash flows provided (used) by operating activities:
Deferred income tax expense (benefit)	55	71
Trading portfolio activity	(3)	13
Realized Investment Gains (Losses)	(36)	10
Equity method investees	262	(91)
Amortization of investments	(4)	0
Depreciation and amortization	21	19
Changes in:
Receivables, net	(317)	(157)
Accrued investment income	(22)	(25)
Deferred acquisition costs	(23)	(13)
Insurance reserves	511	304
Other assets	(89)	(34)
Other liabilities	(168)	(235)
Other, net	9	19
Total adjustments	268	(139)
Net cash flows provided (used) by operating activities	334	94
Dispositions:
Fixed maturity securities - sales	1,722	1,144
Fixed maturity securities - maturities, calls and redemptions	490	1,144
Equity securities	4	2
Limited partnerships	89	20
Mortgage loans	22	3
Purchases:
Fixed maturity securities	(2,238)	(1,919)
Equity securities	0	(5)
Limited partnerships	(169)	(34)
Mortgage loans	(19)	(8)
Change in other investments	0	7
Change in short term investments	16	190
Purchases of property and equipment	(33)	(20)
Disposals of property and equipment	107	0
Other, net	0	2
Net cash flows provided (used) by investing activities	(9)	526
Cash Flows from Financing Activities
Dividends paid to common stockholders	(609)	(608)
Proceeds from the issuance of debt	498	0
Repayment of debt	(358)	0
Other, net	0	5
Net cash flows provided (used) by financing activities	(469)	(603)
Effect of foreign exchange rate changes on cash	(1)	(6)
Net change in cash	(145)	11
Cash, beginning of year	387	190
Cash, end of period	$ 242	$ 201

Consolidated Statements of Stoc

Consolidated Statements of Stockholders' Equity $ in Millions	USD ($)
Balance, beginning of year at Dec. 31, 2014	$ 683
Balance, end of period at Mar. 31, 2015	683
Balance, beginning of year at Dec. 31, 2014	2,151
Additional Paid-In Capital
Stock-based compensation	(8)
Balance, end of period at Mar. 31, 2015	2,143
Balance, beginning of year at Dec. 31, 2014	9,645
Retained Earnings (Accumulated Deficit)
Dividends paid to common stockholders	(608)
Net Income (Loss)	233
Balance, end of period at Mar. 31, 2015	9,270
Accumulated other comprehensive income (loss), beginning balance at Dec. 31, 2014	400
Accumulated Other Comprehensive Income (Loss)
Other Comprehensive Income (Loss)	21
Accumulated other comprehensive income (loss), ending balance at Mar. 31, 2015	421
Balance, beginning of year at Dec. 31, 2014	(84)
Treasury Stock
Stock Based Compensation and Other	5
Balance, end of period at Mar. 31, 2015	(79)
Balance, beginning of year at Dec. 31, 2014	(1)
Balance, end of period at Mar. 31, 2015	(1)
Notes Receivable for the Issuance of Common Stock
Total stockholder's equity	12,437
Total stockholder's equity	11,756
Balance, beginning of year at Dec. 31, 2015	683
Balance, end of period at Mar. 31, 2016	683
Balance, beginning of year at Dec. 31, 2015	2,153
Additional Paid-In Capital
Stock-based compensation	(7)
Balance, end of period at Mar. 31, 2016	2,146
Balance, beginning of year at Dec. 31, 2015	9,313
Retained Earnings (Accumulated Deficit)
Dividends paid to common stockholders	(609)
Net Income (Loss)	66
Balance, end of period at Mar. 31, 2016	8,770
Accumulated other comprehensive income (loss), beginning balance at Dec. 31, 2015	(315)
Accumulated Other Comprehensive Income (Loss)
Other Comprehensive Income (Loss)	259
Accumulated other comprehensive income (loss), ending balance at Mar. 31, 2016	(56)
Balance, beginning of year at Dec. 31, 2015	(78)
Treasury Stock
Stock Based Compensation and Other	5
Balance, end of period at Mar. 31, 2016	(73)
Balance, beginning of year at Dec. 31, 2015	0
Balance, end of period at Mar. 31, 2016	0
Notes Receivable for the Issuance of Common Stock
Total stockholder's equity	$ 11,470

General

General	3 Months Ended
	Mar. 31, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization, Consolidation, Basis of Presentation, Business Description and Accounting Policies [Text Block]	Note A . General Basis of Presentation The Condensed Consolidated Financial Statements include the accounts of CNA Financial Corporation (CNAF) and its subsidiaries. Collectively, CNAF and its subsidiaries are referred to as CNA or the Company. Loews Corporation (Loews) owned approximately 90% of the outstanding common stock of CNAF as of March 31, 2016 . The accompanying Condensed Consolidated Financial Statements have been prepared in conformity with accounting principles generally accepted in the United States of America (GAAP). Intercompany amounts have been eliminated. Certain financial information that is normally included in annual financial statements, including certain financial statement notes, prepared in accordance with GAAP, is not required for interim reporting purposes and has been condensed or omitted. These statements should be read in conjunction with the Consolidated Financial Statements and notes thereto included in CNAF's Annual Report on Form 10-K filed with the Securities and Exchange Commission for the year ended December 31, 2015 , including the summary of significant accounting policies in Note A. The preparation of Condensed Consolidated Financial Statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the Condensed Consolidated Financial Statements and the reported amounts of revenues and expenses during the reporting period. Actual results may differ from those estimates. The interim financial data as of March 31, 2016 and for the three months ended March 31, 2016 and 2015 is unaudited. However, in the opinion of management, the interim data includes all adjustments, including normal recurring adjustments, necessary for a fair statement of the Company's results for the interim periods. The results of operations for the interim periods are not necessarily indicative of the results to be expected for the full year. Recently Adopted Accounting Standards Updates (ASU) In April 2015, the Financial Accounting Standards Board (FASB) issued ASU No. 2015-03, Interest-Imputation of Interest (Subtopic 835-30): Simplifying the Presentation of Debt Issuance Costs . The updated accounting guidance requires debt issuance costs to be presented as a deduction from the corresponding debt liability instead of the historical presentation as an unamortized debt issuance asset. As of January 1, 2016, the Company adopted the updated accounting guidance retrospectively. The Company adjusted its previously reported financial information included herein to reflect the change in accounting guidance for debt issuance costs. The impacts of adopting the new accounting standard on the Company’s Consolidated Balance Sheet as of December 31, 2015, were a decrease in Other assets and a decrease in Long term debt of $2 million . In May 2015, the FASB issued ASU No. 2015-07, Fair Value Measurement (Topic 820): Disclosures for Investments in Certain Entities That Calculate Net Asset Value per Share (or Its Equivalent). The updated accounting guidance removes the requirement to categorize assets measured at fair value utilizing the net asset value per share (or equivalent) practical expedient within the fair value hierarchy. As of January 1, 2016, the Company adopted the updated accounting guidance retrospectively. The Company adjusted its previously reported financial information included herein to reflect the change in accounting guidance for assets measured using the net asset value. The impacts of adopting the new accounting standard resulted in excluding overseas deposits of $28 million and $27 million from the fair value level disclosure as of March 31, 2016 and December 31, 2015 . Recently Issued ASUs In May 2015, the FASB issued ASU No. 2015-09, Financial Services-Insurance (Topic 944): Disclosures about Short-Duration Contracts. The updated accounting guidance requires enhanced disclosures to provide additional information about insurance liabilities for short-duration contracts. The guidance is effective for annual periods beginning after December 15, 2015, and interim periods within the annual periods beginning after December 15, 2016. The Company is currently evaluating the effect the updated guidance will have on the Company's financial statement disclosures. In January 2016, the FASB issued ASU No. 2016-01, Financial Instruments-Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities. The updated accounting guidance requires changes to the reporting model for financial instruments. The guidance is effective for interim and annual periods beginning after December 15, 2017. The Company is currently evaluating the effect the guidance will have on the Company's financial statements, and expects the primary change for the Company to be the requirement for equity investments (except those accounted for under the equity method of accounting or those that result in consolidation of the investee) to be measured at fair value with changes in fair value recognized in net income. In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842): Accounting for Leases. The updated accounting guidance requires lessees to recognize on the balance sheet the assets and liabilities for the rights and obligations created by all leases, including those historically accounted for as operating leases. The guidance is effective for interim and annual periods beginning after December 15, 2018. The Company is currently evaluating the effect the updated guidance will have on the Company's financial statements. In March 2016, the FASB issued ASU No. 2016-09, Compensation-Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting. The updated accounting guidance simplifies the accounting for share-based payment award transactions including income tax consequences, classification of awards as either equity or liabilities and classification on the statement of cash flows. The guidance is effective for annual periods beginning after December 15, 2017, and interim periods within annual periods beginning December 15, 2018. The Company is currently evaluating the effect the updated guidance will have on the Company’s financial statements.

Earnings Per Share

Earnings Per Share	3 Months Ended
	Mar. 31, 2016
Earnings Per Share [Abstract]
Earnings Per Share [Text Block]	Note B . Earnings Per Share Earnings per share is based on the weighted average number of outstanding common shares. Basic earnings (loss) per share excludes the effect of dilutive securities and is computed by dividing Net income (loss) by the weighted average number of common shares outstanding for the period. Diluted earnings (loss) per share reflects the potential dilution that could occur if securities or other contracts to issue common stock were exercised or converted into common stock. For the three months ended March 31, 2016 and 2015 , approximately 542 thousand and 654 thousand potential shares attributable to exercises under stock-based employee compensation plans were included in the calculation of diluted earnings per share. For those same periods, approximately 180 thousand and 182 thousand potential shares attributable to exercises under stock-based employee compensation plans were not included in the calculation of diluted earnings per share because the effect would have been antidilutive.

Investments

Investments	3 Months Ended
	Mar. 31, 2016
Investments [Abstract]
Investments	Note C . Investments The significant components of Net investment income are presented in the following table. Three months ended March 31 (In millions) 2016 2015 Fixed maturity securities $ 446 $ 443 Equity securities 3 3 Limited partnership investments (14 ) 114 Mortgage loans 9 8 Short term investments 3 2 Trading portfolio 2 2 Gross investment income 449 572 Investment expense (14 ) (14 ) Net investment income $ 435 $ 558 Net realized investment gains (losses) are presented in the following table. Three months ended March 31 (In millions) 2016 2015 Net realized investment gains (losses): Fixed maturity securities: Gross realized gains $ 45 $ 33 Gross realized losses (62 ) (21 ) Net realized investment gains (losses) on fixed maturity securities (17 ) 12 Equity securities: Gross realized gains — 1 Gross realized losses (5 ) (1 ) Net realized investment gains (losses) on equity securities (5 ) — Derivative financial instruments (7 ) (1 ) Short term investments and other (7 ) (1 ) Net realized investment gains (losses) $ (36 ) $ 10 Net realized investment losses for the three months ended March 31, 2016 include $8 million related to the redemption of the Company's $350 million senior notes due August 2016. The components of Net other-than-temporary impairment (OTTI) losses recognized in earnings by asset type are presented in the following table. Three months ended March 31 (In millions) 2016 2015 Fixed maturity securities available-for-sale: Corporate and other bonds $ 16 $ 5 States, municipalities and political subdivisions — 5 Asset-backed: Residential mortgage-backed — 1 Other asset-backed 2 — Total asset-backed 2 1 Total fixed maturity securities available-for-sale 18 11 Equity securities available-for-sale: Common stock 5 1 Total equity securities available-for-sale 5 1 OTTI losses recognized in earnings $ 23 $ 12 The following tables present a summary of fixed maturity and equity securities. March 31, 2016 Cost or Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Unrealized OTTI Losses (Gains) (In millions) Fixed maturity securities available-for-sale: Corporate and other bonds $ 17,076 $ 1,255 $ 224 $ 18,107 $ — States, municipalities and political subdivisions 11,478 1,704 3 13,179 (15 ) Asset-backed: Residential mortgage-backed 5,028 197 19 5,206 (33 ) Commercial mortgage-backed 2,137 78 16 2,199 — Other asset-backed 937 4 20 921 — Total asset-backed 8,102 279 55 8,326 (33 ) U.S. Treasury and obligations of government-sponsored enterprises 133 7 — 140 — Foreign government 447 17 1 463 — Redeemable preferred stock 33 2 — 35 — Total fixed maturity securities available-for-sale 37,269 3,264 283 40,250 $ (48 ) Total fixed maturity securities trading 2 2 Equity securities available-for-sale: Common stock 37 6 2 41 Preferred stock 145 5 2 148 Total equity securities available-for-sale 182 11 4 189 Total $ 37,453 $ 3,275 $ 287 $ 40,441 December 31, 2015 Cost or Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Unrealized OTTI Losses (Gains) (In millions) Fixed maturity securities available-for-sale: Corporate and other bonds $ 17,080 $ 1,019 $ 342 $ 17,757 $ — States, municipalities and political subdivisions 11,729 1,453 8 13,174 (4 ) Asset-backed: Residential mortgage-backed 4,935 154 17 5,072 (37 ) Commercial mortgage-backed 2,154 55 12 2,197 — Other asset-backed 923 6 8 921 — Total asset-backed 8,012 215 37 8,190 (37 ) U.S. Treasury and obligations of government-sponsored enterprises 62 5 — 67 — Foreign government 334 13 1 346 — Redeemable preferred stock 33 2 — 35 — Total fixed maturity securities available-for-sale 37,250 2,707 388 39,569 $ (41 ) Total fixed maturity securities trading 3 3 Equity securities available-for-sale: Common stock 46 3 1 48 Preferred stock 145 7 3 149 Total equity securities available-for-sale 191 10 4 197 Total $ 37,444 $ 2,717 $ 392 $ 39,769 The net unrealized gains on investments included in the tables above are recorded as a component of Accumulated other comprehensive income (AOCI). When presented in AOCI, these amounts are net of tax and any required Shadow Adjustments. To the extent that unrealized gains on fixed income securities supporting certain products within the Life & Group Non-Core segment would result in a premium deficiency if realized, a related increase in Insurance reserves is recorded, net of tax, as a reduction of net unrealized gains through Other comprehensive income (loss) (Shadow Adjustments). As of March 31, 2016 and December 31, 2015 , the net unrealized gains on investments included in AOCI were net of after-tax Shadow Adjustments of $1,311 million and $1,111 million . The following tables present the estimated fair value and gross unrealized losses of fixed maturity and equity securities in a gross unrealized loss position by the length of time in which the securities have continuously been in that position. Less than 12 Months 12 Months or Longer Total March 31, 2016 Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses (In millions) Fixed maturity securities available-for-sale: Corporate and other bonds $ 2,669 $ 174 $ 274 $ 50 $ 2,943 $ 224 States, municipalities and political subdivisions 90 3 64 — 154 3 Asset-backed: Residential mortgage-backed 376 11 159 8 535 19 Commercial mortgage-backed 505 14 102 2 607 16 Other asset-backed 572 20 5 — 577 20 Total asset-backed 1,453 45 266 10 1,719 55 U.S. Treasury and obligations of government-sponsored enterprises 23 — — — 23 — Foreign government 54 1 — — 54 1 Redeemable preferred stock 2 — — — 2 — Total fixed maturity securities available-for-sale 4,291 223 604 60 4,895 283 Equity securities available-for-sale: Common stock 6 2 — — 6 2 Preferred stock 17 2 — — 17 2 Total equity securities available-for-sale 23 4 — — 23 4 Total $ 4,314 $ 227 $ 604 $ 60 $ 4,918 $ 287 Less than 12 Months 12 Months or Longer Total December 31, 2015 Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses (In millions) Fixed maturity securities available-for-sale: Corporate and other bonds $ 4,882 $ 302 $ 162 $ 40 $ 5,044 $ 342 States, municipalities and political subdivisions 338 8 75 — 413 8 Asset-backed: Residential mortgage-backed 963 9 164 8 1,127 17 Commercial mortgage-backed 652 10 96 2 748 12 Other asset-backed 552 8 5 — 557 8 Total asset-backed 2,167 27 265 10 2,432 37 U.S. Treasury and obligations of government-sponsored enterprises 4 — — — 4 — Foreign government 54 1 — — 54 1 Redeemable preferred stock 3 — — — 3 — Total fixed maturity securities available-for-sale 7,448 338 502 50 7,950 388 Equity securities available-for-sale: Common stock 3 1 — — 3 1 Preferred stock 13 3 — — 13 3 Total equity securities available-for-sale 16 4 — — 16 4 Total $ 7,464 $ 342 $ 502 $ 50 $ 7,966 $ 392 Based on current facts and circumstances, the Company believes the unrealized losses presented in the March 31, 2016 table above, are not indicative of the ultimate collectibility of the current amortized cost of the securities, but rather are attributable to changes in interest rates, credit spreads and other factors, including volatility in the energy and metals and mining sectors. As of March 31, 2016 , the Company held fixed maturity securities and equity securities with an estimated fair value of $2,446 million and a cost or amortized cost of $2,464 million in the energy and metals and mining sectors. The portion of these securities in a gross unrealized loss position had an estimated fair value of $1,069 million and a cost or amortized cost of $1,202 million. The Company has no current intent to sell securities with unrealized losses, nor is it more likely than not that it will be required to sell prior to recovery of amortized cost; accordingly, the Company has determined that there are no additional OTTI losses to be recorded as of March 31, 2016 . The following table presents the activity related to the pretax credit loss component reflected in Retained earnings on fixed maturity securities still held as of March 31, 2016 and 2015 for which a portion of an OTTI loss was recognized in Other comprehensive income (loss). Three months ended March 31 (In millions) 2016 2015 Beginning balance of credit losses on fixed maturity securities $ 53 $ 62 Additional credit losses for securities for which an OTTI loss was previously recognized — — Reductions for securities sold during the period (5 ) (1 ) Reductions for securities the Company intends to sell or more likely than not will be required to sell — — Ending balance of credit losses on fixed maturity securities $ 48 $ 61 Contractual Maturity The following table presents available-for-sale fixed maturity securities by contractual maturity. March 31, 2016 December 31, 2015 (In millions) Amortized Cost Estimated Fair Value Amortized Cost Estimated Fair Value Due in one year or less $ 1,747 $ 1,773 $ 1,574 $ 1,595 Due after one year through five years 8,335 8,748 7,721 8,070 Due after five years through ten years 14,587 15,129 14,652 14,915 Due after ten years 12,600 14,600 13,303 14,989 Total $ 37,269 $ 40,250 $ 37,250 $ 39,569 Actual maturities may differ from contractual maturities because certain securities may be called or prepaid. Securities not due at a single date are allocated based on weighted average life. Derivative Financial Instruments The Company holds an embedded derivative on funds withheld liability with a notional value of $178 million and $179 million as of March 31, 2016 and December 31, 2015 and a fair value of $1 million and $(5) million as of March 31, 2016 and December 31, 2015 . The embedded derivative on funds withheld liability is accounted for separately and reported with the funds withheld liability in Other liabilities on the Condensed Consolidated Balance Sheets. Investment Commitments As of March 31, 2016 , the Company had committed approximately $371 million to future capital calls from various third-party limited partnership investments in exchange for an ownership interest in the related partnerships. As of March 31, 2016 , the Company had a mortgage loan commitment of $10 million representing a signed loan application received and accepted. The Company invests in various privately placed debt securities, including bank loans, as part of its overall investment strategy and has committed to additional future purchases, sales and funding. Purchases and sales of privately placed debt securities are recorded once funded. As of March 31, 2016 , the Company had commitments to purchase or fund additional amounts of $163 million and sell $166 million under the terms of such securities.

Fair Value

Fair Value	3 Months Ended
	Mar. 31, 2016
Fair Value Disclosures [Abstract]
Fair Value	Note D . Fair Value Fair value is the price that would be received upon sale of an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. The following fair value hierarchy is used in selecting inputs, with the highest priority given to Level 1, as these are the most transparent or reliable. Level 1 - Quoted prices for identical instruments in active markets. Level 2 - Quoted prices for similar instruments in active markets; quoted prices for identical or similar instruments in markets that are not active; and model-derived valuations in which all significant inputs are observable in active markets. Level 3 - Valuations derived from valuation techniques in which one or more significant inputs are not observable. Prices may fall within Level 1, 2 or 3 depending upon the methodology and inputs used to estimate fair value for each specific security. In general the Company seeks to price securities using third-party pricing services. Securities not priced by pricing services are submitted to independent brokers for valuation and, if those are not available, internally developed pricing models are used to value assets using a methodology and inputs the Company believes market participants would use to value the assets. Prices obtained from third-party pricing services or brokers are not adjusted by the Company. The Company performs control procedures over information obtained from pricing services and brokers to ensure prices received represent a reasonable estimate of fair value and to confirm representations regarding whether inputs are observable or unobservable. Procedures include i) the review of pricing service or broker pricing methodologies, ii) back-testing, where past fair value estimates are compared to actual transactions executed in the market on similar dates, iii) exception reporting, where period-over-period changes in price are reviewed and challenged with the pricing service or broker based on exception criteria, iv) deep dives, where the Company performs an independent analysis of the inputs and assumptions used to price individual securities and v) pricing validation, where prices received are compared to prices independently estimated by the Company. Assets and Liabilities Measured at Fair Value Assets and liabilities measured at fair value on a recurring basis are presented in the following tables. March 31, 2016 Total Assets/Liabilities at Fair Value (In millions) Level 1 Level 2 Level 3 Assets Fixed maturity securities: Corporate and other bonds $ — $ 17,916 $ 193 $ 18,109 States, municipalities and political subdivisions — 13,177 2 13,179 Asset-backed: Residential mortgage-backed — 5,078 128 5,206 Commercial mortgage-backed — 2,172 27 2,199 Other asset-backed — 871 50 921 Total asset-backed — 8,121 205 8,326 U.S. Treasury and obligations of government-sponsored enterprises 139 1 — 140 Foreign government — 463 — 463 Redeemable preferred stock 35 — — 35 Total fixed maturity securities 174 39,678 400 40,252 Equity securities 170 — 19 189 Other invested assets — 17 — 17 Short term investments 508 1,064 — 1,572 Life settlement contracts, included in Other assets — — 72 72 Total assets $ 852 $ 40,759 $ 491 $ 42,102 Liabilities Other liabilities $ — $ 1 $ — $ 1 Total liabilities $ — $ 1 $ — $ 1 December 31, 2015 Total Assets/Liabilities at Fair Value (In millions) Level 1 Level 2 Level 3 Assets Fixed maturity securities: Corporate and other bonds $ — $ 17,592 $ 168 $ 17,760 States, municipalities and political subdivisions — 13,172 2 13,174 Asset-backed: Residential mortgage-backed — 4,938 134 5,072 Commercial mortgage-backed — 2,175 22 2,197 Other asset-backed — 868 53 921 Total asset-backed — 7,981 209 8,190 U.S. Treasury and obligations of government-sponsored enterprises 66 1 — 67 Foreign government — 346 — 346 Redeemable preferred stock 35 — — 35 Total fixed maturity securities 101 39,092 379 39,572 Equity securities 177 — 20 197 Other invested assets — 17 — 17 Short term investments 448 1,134 — 1,582 Life settlement contracts, included in Other assets — — 74 74 Total assets $ 726 $ 40,243 $ 473 $ 41,442 Liabilities Other liabilities $ — $ (5 ) $ — $ (5 ) Total liabilities $ — $ (5 ) $ — $ (5 ) The tables below present a reconciliation for all assets and liabilities measured at fair value on a recurring basis using significant unobservable inputs (Level 3). Level 3 (In millions) Balance as of January 1, 2016 Net realized investment gains (losses) and net change in unrealized appreciation (depreciation) included in Net income (loss)* Net change in unrealized appreciation (depreciation) included in Other comprehensive income (loss) Purchases Sales Settlements Transfers into Level 3 Transfers out of Level 3 Balance as of March 31, 2016 Unrealized gains (losses) on Level 3 assets and liabilities held as of March 31, 2016 recognized in Net income (loss)* Fixed maturity securities: Corporate and other bonds $ 168 $ (1 ) $ 4 $ 53 $ (16 ) $ (3 ) $ — $ (12 ) $ 193 $ — States, municipalities and political subdivisions 2 — — — — — — — 2 — Asset-backed: Residential mortgage-backed 134 1 — — — (5 ) — (2 ) 128 — Commercial mortgage-backed 22 — — 9 — — — (4 ) 27 — Other asset-backed 53 — — — — — 2 (5 ) 50 — Total asset-backed 209 1 — 9 — (5 ) 2 (11 ) 205 — Total fixed maturity securities 379 — 4 62 (16 ) (8 ) 2 (23 ) 400 — Equity securities 20 — (1 ) — — — — — 19 — Life settlement contracts 74 4 — — — (6 ) — — 72 1 Total $ 473 $ 4 $ 3 $ 62 $ (16 ) $ (14 ) $ 2 $ (23 ) $ 491 $ 1 Level 3 (In millions) Balance as of January 1, 2015 Net realized investment gains (losses) and net change in unrealized appreciation (depreciation) included in Net income (loss)* Net change in unrealized appreciation (depreciation) included in Other comprehensive income (loss) Purchases Sales Settlements Transfers into Level 3 Transfers out of Level 3 Balance as of March 31, 2015 Unrealized gains (losses) on Level 3 assets and liabilities held as of March 31, 2015 recognized in Net income (loss)* Fixed maturity securities: Corporate and other bonds $ 162 $ 1 $ — $ 12 $ (12 ) $ (14 ) $ 37 $ — $ 186 $ — States, municipalities and political subdivisions 94 1 — — — (9 ) — — 86 — Asset-backed: Residential mortgage-backed 189 1 — 72 — (10 ) — (20 ) 232 — Commercial mortgage-backed 83 1 1 6 — (1 ) — (26 ) 64 — Other asset-backed 655 1 9 35 (144 ) (3 ) — — 553 — Total asset-backed 927 3 10 113 (144 ) (14 ) — (46 ) 849 — Total fixed maturity securities 1,183 5 10 125 (156 ) (37 ) 37 (46 ) 1,121 — Equity securities 16 — (3 ) — — — — — 13 — Life settlement contracts 82 13 — — — (16 ) — — 79 1 Total $ 1,281 $ 18 $ 7 $ 125 $ (156 ) $ (53 ) $ 37 $ (46 ) $ 1,213 $ 1 *Net realized and unrealized gains and losses from Level 3 securities and derivatives are reported in Net income (loss) as follows: Major Category of Assets and Liabilities Condensed Consolidated Statements of Operations Line Items Fixed maturity securities available-for-sale Net realized investment gains (losses) Fixed maturity securities trading Net investment income Equity securities Net realized investment gains (losses) Other invested assets - Derivative financial instruments held in a trading portfolio Net investment income Other invested assets - Derivative financial instruments not held in a trading portfolio Net realized investment gains (losses) Life settlement contracts Other revenues Other liabilities - Derivative financial instruments Net realized investment gains (losses) Securities shown on the previous pages may be transferred in or out of levels within the fair value hierarchy based on the availability of observable market information and quoted prices used to determine the fair value of the security. The availability of observable market information and quoted prices varies based on market conditions and trading volume. During the three months ended March 31, 2016 and 2015 there were no transfers between Level 1 and Level 2. The Company's policy is to recognize transfers between levels at the beginning of quarterly reporting periods. Valuation Methodologies and Inputs The following section describes the valuation methodologies and relevant inputs used to measure different financial instruments at fair value, including an indication of the level in the fair value hierarchy in which the instruments are generally classified. Fixed Maturity Securities Level 1 securities include highly liquid and exchange traded bonds and redeemable preferred stock, valued using quoted market prices. Level 2 securities include most other fixed maturity securities as the significant inputs are observable in the marketplace. All classes of Level 2 fixed maturity securities are valued using a methodology based on information generated by market transactions involving identical or comparable assets, a discounted cash flow methodology, or a combination of both when necessary. Common inputs for all classes of fixed maturity securities include prices from recently executed transactions of similar securities, marketplace quotes, benchmark yields, spreads off benchmark yields, interest rates and U.S. Treasury or swap curves. Specifically for asset-backed securities, key inputs include prepayment and default projections based on past performance of the underlying collateral and current market data. Fixed maturity securities are primarily assigned to Level 3 in cases where broker/dealer quotes are significant inputs to the valuation and there is a lack of transparency as to whether these quotes are based on information that is observable in the marketplace. Level 3 securities also include private placement debt securities whose fair value is determined using internal models with inputs that are not market observable. Equity Securities Level 1 equity securities include publicly traded securities valued using quoted market prices. Level 2 securities are primarily non-redeemable preferred stocks and common stocks valued using pricing for similar securities, recently executed transactions and other pricing models utilizing market observable inputs. Level 3 securities are primarily priced using broker/dealer quotes and internal models with inputs that are not market observable. Derivative Financial Investments Level 2 securities primarily include the embedded derivative on funds withheld liability. The embedded derivative on funds withheld liability is valued using the change in fair value of the assets supporting the funds withheld liability, which are fixed maturity securities valued with observable inputs. Short Term Investments Securities that are actively traded or have quoted prices are classified as Level 1. These securities include money market funds and treasury bills. Level 2 primarily includes commercial paper, for which all inputs are market observable. Fixed maturity securities purchased within one year of maturity are classified consistent with fixed maturity securities discussed above. Short term investments as presented in the tables above differ from the amounts presented on the Condensed Consolidated Balance Sheets because certain short term investments, such as time deposits, are not measured at fair value. Life Settlement Contracts The fair values of life settlement contracts are determined as the present value of the anticipated death benefits less anticipated premium payments based on contract terms that are distinct for each insured, as well as the Company's own assumptions for mortality, premium expense and the rate of return that a buyer would require on the contracts, as no comparable market pricing data is available. Other invested assets - Federal Home Loan Bank of Chicago (FHLBC) Stock The fair value of FHLBC stock is equal to par because it can only be redeemed by the FHLBC at par or sold to another member of the FHLBC at par and is classified as Level 2. Other invested assets - Overseas Deposits As of March 31, 2016 and December 31, 2015, there were approximately $28 million and $27 million respectively of overseas deposits, which can be redeemed at net asset value in 90 days or less. Overseas deposits are excluded from the fair value hierarchy because their fair value is recorded using the net asset value per share (or equivalent) practical expedient. Significant Unobservable Inputs The following tables present quantitative information about the significant unobservable inputs utilized by the Company in the fair value measurements of Level 3 assets. Valuations for assets and liabilities not presented in the tables below are primarily based on broker/dealer quotes for which there is a lack of transparency as to inputs used to develop the valuations. The quantitative detail of these unobservable inputs is neither provided nor reasonably available to the Company. March 31, 2016 Estimated Fair Value (In millions) Valuation Technique(s) Unobservable Input(s) Range (Weighted Average) Fixed maturity securities $ 142 Discounted cash flow Credit spread 0% - 20% (4%) Life settlement contracts 72 Discounted cash flow Discount rate risk premium 9% Mortality assumption 55% - 1676% (164%) December 31, 2015 Estimated Fair Value Valuation Technique(s) Unobservable Input(s) Range (Weighted Average) Fixed maturity securities $ 138 Discounted cash flow Credit spread 3% - 184% (6%) Life settlement contracts 74 Discounted cash flow Discount rate risk premium 9% Mortality assumption 55% - 1676% (164%) For fixed maturity securities, an increase to the credit spread assumptions would result in a lower fair value measurement. For life settlement contracts, an increase in the discount rate risk premium or decrease in the mortality assumption would result in a lower fair value measurement. Financial Assets and Liabilities Not Measured at Fair Value The carrying amount and estimated fair value of the Company's financial assets and liabilities which are not measured at fair value on the Condensed Consolidated Balance Sheets are presented in the following tables. March 31, 2016 Carrying Amount Estimated Fair Value (In millions) Level 1 Level 2 Level 3 Total Assets Mortgage loans $ 675 $ — $ — $ 697 $ 697 Liabilities Long term debt $ 2,708 $ — $ 2,943 $ — $ 2,943 December 31, 2015 Carrying Estimated Fair Value (In millions) Level 1 Level 2 Level 3 Total Assets Mortgage loans $ 678 $ — $ — $ 688 $ 688 Liabilities Short term debt $ 350 $ — $ 360 $ — $ 360 Long term debt 2,210 — 2,433 — 2,433 The following methods and assumptions were used to estimate the fair value of these financial assets and liabilities. The fair value of Mortgage loans was based on the present value of the expected future cash flows discounted at the current interest rate for origination of similar quality loans, adjusted for specific loan risk. The Company's senior notes and debentures were valued based on observable market prices. The fair value for other debt was estimated using discounted cash flows based on current incremental borrowing rates for similar borrowing arrangements. The carrying amounts reported on the Condensed Consolidated Balance Sheets for Cash, Short term investments not carried at fair value, Accrued investment income and certain Other assets and Other liabilities approximate fair value due to the short term nature of these items. These assets and liabilities are not listed in the tables above.

Claim and Claim Adjustment Expe

Claim and Claim Adjustment Expense Reserves	3 Months Ended
	Mar. 31, 2016
Liability for Claims and Claims Adjustment Expense [Abstract]
Claim and Claim Adjustment Expense Reserves	Note E . Claim and Claim Adjustment Expense Reserves The Company's property and casualty insurance claim and claim adjustment expense reserves represent the estimated amounts necessary to resolve all outstanding claims, including incurred but not reported (IBNR) claims as of the reporting date. The Company's reserve projections are based primarily on detailed analysis of the facts in each case, the Company's experience with similar cases and various historical development patterns. Consideration is given to such historical patterns as field reserving trends and claims settlement practices, loss payments, pending levels of unpaid claims and product mix, as well as court decisions, economic conditions including inflation and public attitudes. All of these factors can affect the estimation of claim and claim adjustment expense reserves. Establishing claim and claim adjustment expense reserves, including claim and claim adjustment expense reserves for catastrophic events that have occurred, is an estimation process. Many factors can ultimately affect the final settlement of a claim and, therefore, the necessary reserve. Changes in the law, results of litigation, medical costs, the cost of repair materials and labor rates can all affect ultimate claim costs. In addition, time can be a critical part of reserving determinations since the longer the span between the incidence of a loss and the payment or settlement of the claim, the more variable the ultimate settlement amount can be. Accordingly, short-tail claims, such as property damage claims, tend to be more reasonably estimable than long-tail claims, such as workers' compensation, general liability and professional liability claims. Adjustments to prior year reserve estimates, if necessary, are reflected in the results of operations in the period that the need for such adjustments is determined. There can be no assurance that the Company's ultimate cost for insurance losses will not exceed current estimates. Catastrophes are an inherent risk of the property and casualty insurance business and have contributed to material period-to-period fluctuations in the Company's results of operations and/or equity. The Company reported catastrophe losses, net of reinsurance, of $36 million and $29 million for the three months ended March 31, 2016 and 2015 . Catastrophe losses in 2016 related primarily to U.S. weather-related events. Net Prior Year Development The following tables and discussion present the net prior year development. Three months ended March 31, 2016 (In millions) Specialty Commercial International Corporate & Other Non-Core Total Pretax (favorable) unfavorable net prior year claim and allocated claim adjustment expense reserve development $ (34 ) $ (14 ) $ (4 ) $ — $ (52 ) Pretax (favorable) unfavorable premium development (11 ) (2 ) (1 ) — (14 ) Total pretax (favorable) unfavorable net prior year development $ (45 ) $ (16 ) $ (5 ) $ — $ (66 ) Three months ended March 31, 2015 (In millions) Specialty Commercial International Corporate & Other Non-Core Total Pretax (favorable) unfavorable net prior year claim and allocated claim adjustment expense reserve development $ 2 $ (5 ) $ (4 ) $ — $ (7 ) Pretax (favorable) unfavorable premium development (6 ) (1 ) 16 — 9 Total pretax (favorable) unfavorable net prior year development $ (4 ) $ (6 ) $ 12 $ — $ 2 Specialty The following table presents further detail of the net prior year claim and allocated claim adjustment expense reserve development (development) recorded for the Specialty segment. Three months ended March 31 (In millions) 2016 2015 Pretax (favorable) unfavorable development: Medical Professional Liability $ (7 ) $ 14 Other Professional Liability and Management Liability (9 ) (3 ) Surety — 1 Warranty 2 — Other (20 ) (10 ) Total pretax (favorable) unfavorable development $ (34 ) $ 2 2016 Favorable development for medical professional liability was due to lower than expected severity in accident years 2011 and prior. This was partially offset by unfavorable development in accident years 2012 and 2013 recorded related to higher than expected large loss emergence and higher than expected severity in accident years 2014 and 2015. Favorable development in other professional liability and management liability was primarily related to favorable settlements on claims in accident years 2011 through 2013. This was partially offset by unfavorable development recorded related to a specific financial institutions claim in accident year 2014 and continued deterioration on claims in accident year 2009 related to the credit crisis. Favorable development for other coverages was primarily due to better than expected claim frequency in property coverages provided to Specialty customers in accident year 2015. 2015 Overall, unfavorable development for medical professional liability was primarily related to increased frequency in the Aging Services book for accident years 2013 and 2014, partially offset by better than expected severity in accident years 2010 and prior. Favorable development for other coverage was primarily due to better than expected frequency in property coverages provided to Specialty customers in accident year 2014. Commercial The following table presents further detail of the development recorded for the Commercial segment. Three months ended March 31 (In millions) 2016 2015 Pretax (favorable) unfavorable development: Commercial Auto $ (15 ) $ — General Liability (15 ) 4 Workers' Compensation 4 (1 ) Property and Other 12 (8 ) Total pretax (favorable) unfavorable development $ (14 ) $ (5 ) 2016 Favorable development for commercial auto was primarily due to favorable settlements on claims in accident years 2011 through 2014. Favorable development for general liability was primarily due to favorable settlements on claims in accident years 2013 and 2014. Unfavorable development for property and other was primarily due to higher than expected severity from a 2015 catastrophe event. 2015 Favorable development for property and other was due to lower than expected loss emergence from 2014 catastrophe events. International The following table presents further detail of the development recorded for the International segment. Three months ended March 31 (In millions) 2016 2015 Pretax (favorable) unfavorable development: Medical Professional Liability $ — $ — Other Professional Liability (1 ) — Liability — (5 ) Property & Marine (4 ) (6 ) Other 1 7 Total pretax (favorable) unfavorable development $ (4 ) $ (4 ) Asbestos and Environmental Pollution Reserves (A&EP) In 2010, Continental Casualty Company (CCC) together with several of the Company’s insurance subsidiaries completed a transaction with National Indemnity Company (NICO), a subsidiary of Berkshire Hathaway Inc., under which substantially all of the Company’s legacy A&EP liabilities were ceded to the NICO Loss Portfolio Transfer (Loss Portfolio Transfer or LPT). At the effective date of the transaction, the Company ceded approximately $1.6 billion of net A&EP claim and allocated claim adjustment expense reserves to NICO under a retroactive reinsurance agreement with an aggregate limit of $4 billion . The $1.6 billion of claim and allocated claim adjustment expense reserves ceded to NICO was net of $1.2 billion of ceded claim and allocated claim adjustment expense reserves under existing third-party reinsurance contracts. The NICO LPT aggregate reinsurance limit also covers credit risk on the existing third-party reinsurance related to these liabilities. The Company paid NICO a reinsurance premium of $2 billion and transferred to NICO billed third-party reinsurance receivables related to A&EP claims with a net book value of $215 million , resulting in total consideration of $2.2 billion . Through December 31, 2013, the Company recognized $0.9 billion of additional amounts ceded under the LPT. As a result, the cumulative amounts ceded under the LPT exceeded the $2.2 billion consideration paid, resulting in the NICO LPT moving into a gain position, requiring deferred retroactive reinsurance accounting treatment. This deferred gain is recognized in earnings in proportion to actual paid recoveries under the LPT. Over the life of the contract, there is no economic impact as long as any additional losses incurred are within the limit of the LPT. In a period in which a change in the estimate of ceded incurred losses is recognized, the change to the deferred gain is cumulatively recognized in earnings as if the revised estimate was available at the effective date of the LPT. The following table presents the impact of the Loss Portfolio Transfer on the Condensed Consolidated Statements of Operations. Three months ended March 31 (In millions) 2016 2015 Net A&EP adverse development before consideration of LPT $ 200 $ — Provision for uncollectible third-party reinsurance on A&EP — — Additional amounts ceded under LPT 200 — Retroactive reinsurance benefit recognized (73 ) (5 ) Pretax impact of unrecognized deferred retroactive reinsurance benefit $ 127 $ (5 ) The Company expected to complete its reserve review of A&EP reserves in the second quarter of 2016; however, during the first quarter of 2016 the Company received communication from NICO that their reserve review indicated a substantial increase in reserves. As a result, the Company accelerated and completed its reserve review during the first quarter. Based upon the Company's accelerated review, net unfavorable development prior to cessions to the LPT of $200 million was recognized; $146 million related to asbestos claims and $54 million related to environmental pollution claims. The unfavorable development was driven by an increase in anticipated future expenses associated with determination of coverage, higher anticipated payouts associated with a limited number of historical accounts having significant asbestos exposures and higher than expected severity on pollution claims. This unfavorable development was ceded to NICO under the LPT; however the Company’s reported earnings were negatively affected due to the application of retroactive reinsurance accounting, as only a portion of the additional amounts ceded under the LPT were recognized in the current quarter. Retroactive reinsurance accounting resulted in the recognition of a reinsurance benefit of $73 million in the current quarter, while the remaining $127 million of incurred losses covered by the LPT will be recognized as a benefit through future earnings in proportion to the actual paid recoveries subject to the NICO LPT. All amounts recognized related to the LPT are recorded within Insurance claims and policyholders’ benefits in the Condensed Consolidated Statement of Operations. As of March 31, 2016 and December 31, 2015 , the cumulative amounts ceded under the LPT were $2.8 billion and $2.6 billion . Cumulative losses recognized in the Company's Condensed Consolidated Statement of Operations that are covered by the LPT were $368 million and $241 million as of March 31, 2016 and December 31, 2015 . NICO established a collateral trust account as security for its obligations to the Company. The fair value of the collateral trust account was $2.7 billion and $2.8 billion as of March 31, 2016 and December 31, 2015 . In addition, Berkshire Hathaway Inc. guaranteed the payment obligations of NICO up to the full aggregate reinsurance limit as well as certain of NICO’s performance obligations under the trust agreement. NICO is responsible for claims handling and billing and collection from third-party reinsurers related to the Company’s A&EP claims.

Legal Proceedings and Contingen

Legal Proceedings and Contingent Liabilities	3 Months Ended
	Mar. 31, 2016
Legal Proceedings and Contingent Liabilities [Abstract]
Legal Proceedings and Contingent Liabilities	Note F . Legal Proceedings and Contingent Liabilities The Company is a party to routine litigation incidental to its business, which, based on the facts and circumstances currently known, is not material to the Condensed Consolidated Financial Statements.

Benefit Plans

Benefit Plans	3 Months Ended
	Mar. 31, 2016
Compensation and Retirement Disclosure [Abstract]
Benefit Plans	Note G . Benefit Plans The components of net periodic cost (benefit) are presented in the following table. Three months ended March 31 (In millions) 2016 2015 Pension cost (benefit) Service cost $ — $ 2 Interest cost on projected benefit obligation 28 28 Expected return on plan assets (40 ) (43 ) Amortization of net actuarial loss 9 9 Net periodic pension cost (benefit) $ (3 ) $ (4 )

Commitments and Contingencies,

Commitments and Contingencies, and Guarantees	3 Months Ended
	Mar. 31, 2016
Commitments and Contingencies Disclosure [Abstract]
Commitments Contingencies and Guarantees [Text Block]	Note H . Commitments, Contingencies and Guarantees Commitments and Contingencies The Company holds an investment in a real estate joint venture in which the Company, on a joint and several basis with the other unrelated shareholders guaranteed to fund operating deficits of the joint venture and an operating lease for an office building entered into by the venture. The lease was terminated in March 2016. In the event that the other parties to the joint venture are unable to meet their commitments in funding this joint venture, the Company would be required to assume future obligations, primarily related to the wind-down of the lease and joint venture. The Company does not believe it is likely that it will be required to do so. However, as of March 31, 2016 , the maximum potential loss that the Company could be required to pay under this guarantee, in excess of amounts already recorded, was approximately $18 million . If the Company were required to assume future obligations, the Company would have the right to pursue reimbursement from the other shareholders. Guarantees As of March 31, 2016 and December 31, 2015 , the Company had recorded liabilities of approximately $5 million related to guarantee and indemnification agreements and management believes that it is not likely that any future indemnity claims will be significantly greater than the amounts recorded. In the course of selling business entities and assets to third parties, the Company agreed to guarantee the performance of certain obligations of a previously owned subsidiary and to indemnify purchasers for losses arising out of breaches of representation and warranties with respect to the business entities or assets sold, including, in certain cases, losses arising from undisclosed liabilities or certain named litigation. Such guarantee and indemnification agreements in effect for sales of business entities, assets and third-party loans may include provisions that survive indefinitely. As of March 31, 2016 , the aggregate amount related to quantifiable guarantees was $375 million and the aggregate amount related to indemnification agreements was $259 million . Should the Company be required to make payments under the guarantee, it would have the right to seek reimbursement in certain cases from an affiliate of a previously owned subsidiary. In addition, the Company has agreed to provide indemnification to third-party purchasers for certain losses associated with sold business entities or assets that are not limited by a contractual monetary amount. As of March 31, 2016 , the Company had outstanding unlimited indemnifications in connection with the sales of certain of its business entities or assets that included tax liabilities arising prior to a purchaser's ownership of an entity or asset, defects in title at the time of sale, employee claims arising prior to closing and in some cases losses arising from certain litigation and undisclosed liabilities. Certain provisions of the indemnification agreements survive indefinitely, while others survive until the applicable statutes of limitation expire, or until the agreed-upon contract terms expire. The Company also provided guarantees, if the primary obligor fails to perform, to holders of structured settlement annuities provided by a previously owned subsidiary. As of March 31, 2016 , the potential amount of future payments the Company could be required to pay under these guarantees was approximately $2.0 billion , which will be paid over the lifetime of the annuitants. The Company does not believe any payment is likely under these guarantees, as the Company is the beneficiary of a trust that must be maintained at a level that approximates the discounted reserves for these annuities.

Accumulated Other Comprehensive

Accumulated Other Comprehensive Income (Loss) by Component	3 Months Ended
	Mar. 31, 2016
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Accumulated Other Comprehensive Income (Loss) by Component	Note I . Accumulated Other Comprehensive Income (Loss) by Component The table below displays the changes in Accumulated other comprehensive income (loss) by component. (In millions) Net unrealized gains (losses) on investments with OTTI losses Net unrealized gains (losses) on other investments Pension and postretirement benefits Cumulative foreign currency translation adjustment Total Balance as of January 1, 2016 $ 27 $ 390 $ (648 ) $ (84 ) $ (315 ) Other comprehensive income (loss) before reclassifications 3 223 — 14 240 Amounts reclassified from accumulated other comprehensive income (loss) net of tax (expense) benefit of $1, $7, $3, $- and $11 (2 ) (11 ) (6 ) — (19 ) Other comprehensive income (loss) net of tax (expense) benefit of $(3), $(116), $(3), $- and $(122) 5 234 6 14 259 Balance as of March 31, 2016 $ 32 $ 624 $ (642 ) $ (70 ) $ (56 ) (In millions) Net unrealized gains (losses) on investments with OTTI losses Net unrealized gains (losses) on other investments Pension and postretirement benefits Cumulative foreign currency translation adjustment Total Balance as of January 1, 2015 $ 36 $ 942 $ (633 ) $ 55 $ 400 Other comprehensive income (loss) before reclassifications (1 ) 121 — (96 ) 24 Amounts reclassified from accumulated other comprehensive income (loss) net of tax (expense) benefit of $-, $-, $3, $- and $3 — 9 (6 ) — 3 Other comprehensive income (loss) net of tax (expense) benefit of $-, $(62), $(3), $- and $(65) (1 ) 112 6 (96 ) 21 Balance as of March 31, 2015 $ 35 $ 1,054 $ (627 ) $ (41 ) $ 421 Amounts reclassified from Accumulated other comprehensive income (loss) shown above are reported in Net income (loss) as follows: Component of AOCI Condensed Consolidated Statements of Operations Line Item Affected by Reclassifications Net unrealized gains (losses) on investments with OTTI losses Net realized investment gains (losses) Net unrealized gains (losses) on other investments Net realized investment gains (losses) Pension and postretirement benefits Other operating expenses

Business Segments

Business Segments	3 Months Ended
	Mar. 31, 2016
Segment Reporting [Abstract]
Business Segments	Note J . Business Segments The Company's core property and casualty commercial insurance operations are aggregated and reported in three business segments: Specialty, Commercial and International. The Company's non-core operations are managed and reported in two segments: Life & Group Non-Core and Corporate & Other Non-Core. The accounting policies of the segments are the same as those described in Note A to the Consolidated Financial Statements within CNAF's Annual Report on Form 10-K for the year ended December 31, 2015 . The Company manages most of its assets on a legal entity basis, while segment operations are generally conducted across legal entities. As such, only Insurance and Reinsurance receivables, Insurance reserves, Deferred acquisition costs and Goodwill are readily identifiable for all individual segments. Distinct investment portfolios are not maintained for every individual segment; accordingly, allocation of assets to each segment is not performed. Therefore, a significant portion of Net investment income and Realized investment gains or losses are allocated primarily based on each segment's net carried insurance reserves, as adjusted. All significant intersegment income and expense has been eliminated. Income taxes have been allocated on the basis of the taxable income of the segments. In the following tables, certain financial measures are presented to provide information used by management to monitor the Company's operating performance. Management utilizes these financial measures to monitor the Company's insurance operations and investment portfolio. Net operating income (loss), which is derived from certain income statement amounts, is used by management to monitor performance of the Company's insurance operations. The Company's investment portfolio is monitored by management through analysis of various factors including unrealized gains and losses on securities, portfolio duration and exposure to market and credit risk. Based on such analyses, the Company may recognize an OTTI loss on an investment security in accordance with its policy, or sell a security, which may produce realized gains and losses. Net operating income (loss) is calculated by excluding from net income (loss) the after-tax effects of 1) net realized investment gains (losses) 2) income or loss from discontinued operations and 3) any cumulative effects of changes in accounting guidance. The calculation of net operating income excludes net realized investment gains (losses) because net realized investment gains (losses) are largely discretionary, except for some losses related to OTTI, and are generally driven by economic factors that are not necessarily consistent with key drivers of underwriting performance, and are therefore not considered an indication of trends in insurance operations. The Company's results of operations and selected balance sheet items by segment are presented in the following tables. Three months ended March 31, 2016 Specialty Commercial International Life & Group Non-Core Corporate & Other Non-Core (In millions) Eliminations Total Operating revenues Net earned premiums $ 682 $ 688 $ 198 $ 131 $ — $ — $ 1,699 Net investment income 107 126 12 187 3 — 435 Other revenues 87 6 1 — 3 — 97 Total operating revenues 876 820 211 318 6 — 2,231 Claims, Benefits and Expenses Net incurred claims and benefits 390 442 121 323 128 — 1,404 Policyholders’ dividends 1 3 — — — — 4 Amortization of deferred acquisition costs 144 116 47 — — — 307 Other insurance related expenses 75 141 28 33 — — 277 Other expenses 75 5 9 3 54 — 146 Total claims, benefits and expenses 685 707 205 359 182 — 2,138 Operating income (loss) before income tax 191 113 6 (41 ) (176 ) — 93 Income tax (expense) benefit on operating income (loss) (64 ) (39 ) — 39 62 — (2 ) Net operating income (loss) 127 74 6 (2 ) (114 ) — 91 Net realized investment gains (losses) (11 ) (18 ) 4 (3 ) (8 ) — (36 ) Income tax (expense) benefit on net realized investment gains (losses) 4 6 (1 ) — 2 — 11 Net realized investment gains (losses), after tax (7 ) (12 ) 3 (3 ) (6 ) — (25 ) Net income (loss) $ 120 $ 62 $ 9 $ (5 ) $ (120 ) $ — $ 66 March 31, 2016 (In millions) Reinsurance receivables $ 765 $ 623 $ 139 $ 496 $ 2,707 $ — $ 4,730 Insurance receivables 884 1,025 276 14 2 — 2,201 Deferred acquisition costs 309 225 88 — — — 622 Goodwill 117 — 33 — — — 150 Insurance reserves Claim and claim adjustment expenses 6,325 9,095 1,395 3,311 2,892 — 23,018 Unearned premiums 1,861 1,347 464 136 — (1 ) 3,807 Future policy benefits — — — 10,500 — — 10,500 Three months ended March 31, 2015 Specialty Commercial International Life & Group Non-Core Corporate & Other Non-Core (In millions) Eliminations Total Operating revenues Net earned premiums $ 680 $ 678 $ 191 $ 138 $ — $ — $ 1,687 Net investment income 155 204 14 179 6 — 558 Other revenues 78 9 — 9 2 (1 ) 97 Total operating revenues 913 891 205 326 8 (1 ) 2,342 Claims, Benefits and Expenses Net incurred claims and benefits 429 454 116 340 (4 ) — 1,335 Policyholders’ dividends 1 3 — — — — 4 Amortization of deferred acquisition costs 144 117 35 7 — — 303 Other insurance related expenses 69 127 37 35 — — 268 Other expenses 67 8 5 4 46 (1 ) 129 Total claims, benefits and expenses 710 709 193 386 42 (1 ) 2,039 Operating income (loss) before income tax 203 182 12 (60 ) (34 ) — 303 Income tax (expense) benefit on operating income (loss) (68 ) (62 ) (3 ) 43 12 — (78 ) Net operating income (loss) 135 120 9 (17 ) (22 ) — 225 Net realized investment gains (losses) 4 4 1 1 — — 10 Income tax (expense) benefit on net realized investment gains (losses) (1 ) (3 ) — 2 — — (2 ) Net realized investment gains (losses), after tax 3 1 1 3 — — 8 Net income (loss) $ 138 $ 121 $ 10 $ (14 ) $ (22 ) $ — $ 233 December 31, 2015 (In millions) Reinsurance receivables $ 724 $ 639 $ 144 $ 497 $ 2,487 $ — $ 4,491 Insurance receivables 890 993 233 11 2 — 2,129 Deferred acquisition costs 307 213 78 — — — 598 Goodwill 117 — 33 — — — 150 Insurance reserves Claim and claim adjustment expenses 6,269 9,183 1,347 3,220 2,644 — 22,663 Unearned premiums 1,839 1,297 415 120 — — 3,671 Future policy benefits — — — 10,152 — — 10,152 The following table presents revenue by line of business for each reportable segment. Revenues are comprised of Operating revenues and Net realized investment gains and losses. Three months ended March 31 (In millions) 2016 2015 Specialty Management & Professional Liability $ 618 $ 697 Surety 127 120 Warranty & Alternative Risks 120 100 Specialty revenues 865 917 Commercial Middle Market 401 409 Small Business 143 165 Other Commercial Insurance 258 321 Commercial revenues 802 895 International Canada 50 55 CNA Europe 78 77 Hardy 87 74 International revenues 215 206 Life & Group Non-Core revenues 315 327 Corporate & Other Non-Core revenues (2 ) 8 Eliminations — (1 ) Total revenues $ 2,195 $ 2,352

General Summary of Significant

General Summary of Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2016
Accounting Policies [Abstract]
Consolidation, Policy [Policy Text Block]	The accompanying Condensed Consolidated Financial Statements have been prepared in conformity with accounting principles generally accepted in the United States of America (GAAP)
Use of Estimates, Policy [Policy Text Block]	The preparation of Condensed Consolidated Financial Statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the Condensed Consolidated Financial Statements and the reported amounts of revenues and expenses during the reporting period. Actual results may differ from those estimates.
New Accounting Pronouncements, Policy [Policy Text Block]	Recently Adopted Accounting Standards Updates (ASU) In April 2015, the Financial Accounting Standards Board (FASB) issued ASU No. 2015-03, Interest-Imputation of Interest (Subtopic 835-30): Simplifying the Presentation of Debt Issuance Costs . The updated accounting guidance requires debt issuance costs to be presented as a deduction from the corresponding debt liability instead of the historical presentation as an unamortized debt issuance asset. As of January 1, 2016, the Company adopted the updated accounting guidance retrospectively. The Company adjusted its previously reported financial information included herein to reflect the change in accounting guidance for debt issuance costs. The impacts of adopting the new accounting standard on the Company’s Consolidated Balance Sheet as of December 31, 2015, were a decrease in Other assets and a decrease in Long term debt of $2 million . In May 2015, the FASB issued ASU No. 2015-07, Fair Value Measurement (Topic 820): Disclosures for Investments in Certain Entities That Calculate Net Asset Value per Share (or Its Equivalent). The updated accounting guidance removes the requirement to categorize assets measured at fair value utilizing the net asset value per share (or equivalent) practical expedient within the fair value hierarchy. As of January 1, 2016, the Company adopted the updated accounting guidance retrospectively. The Company adjusted its previously reported financial information included herein to reflect the change in accounting guidance for assets measured using the net asset value. The impacts of adopting the new accounting standard resulted in excluding overseas deposits of $28 million and $27 million from the fair value level disclosure as of March 31, 2016 and December 31, 2015 . Recently Issued ASUs In May 2015, the FASB issued ASU No. 2015-09, Financial Services-Insurance (Topic 944): Disclosures about Short-Duration Contracts. The updated accounting guidance requires enhanced disclosures to provide additional information about insurance liabilities for short-duration contracts. The guidance is effective for annual periods beginning after December 15, 2015, and interim periods within the annual periods beginning after December 15, 2016. The Company is currently evaluating the effect the updated guidance will have on the Company's financial statement disclosures. In January 2016, the FASB issued ASU No. 2016-01, Financial Instruments-Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities. The updated accounting guidance requires changes to the reporting model for financial instruments. The guidance is effective for interim and annual periods beginning after December 15, 2017. The Company is currently evaluating the effect the guidance will have on the Company's financial statements, and expects the primary change for the Company to be the requirement for equity investments (except those accounted for under the equity method of accounting or those that result in consolidation of the investee) to be measured at fair value with changes in fair value recognized in net income. In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842): Accounting for Leases. The updated accounting guidance requires lessees to recognize on the balance sheet the assets and liabilities for the rights and obligations created by all leases, including those historically accounted for as operating leases. The guidance is effective for interim and annual periods beginning after December 15, 2018. The Company is currently evaluating the effect the updated guidance will have on the Company's financial statements. In March 2016, the FASB issued ASU No. 2016-09, Compensation-Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting. The updated accounting guidance simplifies the accounting for share-based payment award transactions including income tax consequences, classification of awards as either equity or liabilities and classification on the statement of cash flows. The guidance is effective for annual periods beginning after December 15, 2017, and interim periods within annual periods beginning December 15, 2018. The Company is currently evaluating the effect the updated guidance will have on the Company’s financial statements.

Investments (Tables)

Investments (Tables)	3 Months Ended
	Mar. 31, 2016
Investments [Abstract]
Net investment income	The significant components of Net investment income are presented in the following table. Three months ended March 31 (In millions) 2016 2015 Fixed maturity securities $ 446 $ 443 Equity securities 3 3 Limited partnership investments (14 ) 114 Mortgage loans 9 8 Short term investments 3 2 Trading portfolio 2 2 Gross investment income 449 572 Investment expense (14 ) (14 ) Net investment income $ 435 $ 558
Net realized investment gains (losses)	Net realized investment gains (losses) are presented in the following table. Three months ended March 31 (In millions) 2016 2015 Net realized investment gains (losses): Fixed maturity securities: Gross realized gains $ 45 $ 33 Gross realized losses (62 ) (21 ) Net realized investment gains (losses) on fixed maturity securities (17 ) 12 Equity securities: Gross realized gains — 1 Gross realized losses (5 ) (1 ) Net realized investment gains (losses) on equity securities (5 ) — Derivative financial instruments (7 ) (1 ) Short term investments and other (7 ) (1 ) Net realized investment gains (losses) $ (36 ) $ 10
Components of net other than temporary impairment losses recognized in earnings by asset type	The components of Net other-than-temporary impairment (OTTI) losses recognized in earnings by asset type are presented in the following table. Three months ended March 31 (In millions) 2016 2015 Fixed maturity securities available-for-sale: Corporate and other bonds $ 16 $ 5 States, municipalities and political subdivisions — 5 Asset-backed: Residential mortgage-backed — 1 Other asset-backed 2 — Total asset-backed 2 1 Total fixed maturity securities available-for-sale 18 11 Equity securities available-for-sale: Common stock 5 1 Total equity securities available-for-sale 5 1 OTTI losses recognized in earnings $ 23 $ 12
Summary of fixed maturity and equity securities	The following tables present a summary of fixed maturity and equity securities. March 31, 2016 Cost or Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Unrealized OTTI Losses (Gains) (In millions) Fixed maturity securities available-for-sale: Corporate and other bonds $ 17,076 $ 1,255 $ 224 $ 18,107 $ — States, municipalities and political subdivisions 11,478 1,704 3 13,179 (15 ) Asset-backed: Residential mortgage-backed 5,028 197 19 5,206 (33 ) Commercial mortgage-backed 2,137 78 16 2,199 — Other asset-backed 937 4 20 921 — Total asset-backed 8,102 279 55 8,326 (33 ) U.S. Treasury and obligations of government-sponsored enterprises 133 7 — 140 — Foreign government 447 17 1 463 — Redeemable preferred stock 33 2 — 35 — Total fixed maturity securities available-for-sale 37,269 3,264 283 40,250 $ (48 ) Total fixed maturity securities trading 2 2 Equity securities available-for-sale: Common stock 37 6 2 41 Preferred stock 145 5 2 148 Total equity securities available-for-sale 182 11 4 189 Total $ 37,453 $ 3,275 $ 287 $ 40,441 December 31, 2015 Cost or Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Unrealized OTTI Losses (Gains) (In millions) Fixed maturity securities available-for-sale: Corporate and other bonds $ 17,080 $ 1,019 $ 342 $ 17,757 $ — States, municipalities and political subdivisions 11,729 1,453 8 13,174 (4 ) Asset-backed: Residential mortgage-backed 4,935 154 17 5,072 (37 ) Commercial mortgage-backed 2,154 55 12 2,197 — Other asset-backed 923 6 8 921 — Total asset-backed 8,012 215 37 8,190 (37 ) U.S. Treasury and obligations of government-sponsored enterprises 62 5 — 67 — Foreign government 334 13 1 346 — Redeemable preferred stock 33 2 — 35 — Total fixed maturity securities available-for-sale 37,250 2,707 388 39,569 $ (41 ) Total fixed maturity securities trading 3 3 Equity securities available-for-sale: Common stock 46 3 1 48 Preferred stock 145 7 3 149 Total equity securities available-for-sale 191 10 4 197 Total $ 37,444 $ 2,717 $ 392 $ 39,769
Securities in a gross unrealized loss position	The following tables present the estimated fair value and gross unrealized losses of fixed maturity and equity securities in a gross unrealized loss position by the length of time in which the securities have continuously been in that position. Less than 12 Months 12 Months or Longer Total March 31, 2016 Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses (In millions) Fixed maturity securities available-for-sale: Corporate and other bonds $ 2,669 $ 174 $ 274 $ 50 $ 2,943 $ 224 States, municipalities and political subdivisions 90 3 64 — 154 3 Asset-backed: Residential mortgage-backed 376 11 159 8 535 19 Commercial mortgage-backed 505 14 102 2 607 16 Other asset-backed 572 20 5 — 577 20 Total asset-backed 1,453 45 266 10 1,719 55 U.S. Treasury and obligations of government-sponsored enterprises 23 — — — 23 — Foreign government 54 1 — — 54 1 Redeemable preferred stock 2 — — — 2 — Total fixed maturity securities available-for-sale 4,291 223 604 60 4,895 283 Equity securities available-for-sale: Common stock 6 2 — — 6 2 Preferred stock 17 2 — — 17 2 Total equity securities available-for-sale 23 4 — — 23 4 Total $ 4,314 $ 227 $ 604 $ 60 $ 4,918 $ 287 Less than 12 Months 12 Months or Longer Total December 31, 2015 Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses (In millions) Fixed maturity securities available-for-sale: Corporate and other bonds $ 4,882 $ 302 $ 162 $ 40 $ 5,044 $ 342 States, municipalities and political subdivisions 338 8 75 — 413 8 Asset-backed: Residential mortgage-backed 963 9 164 8 1,127 17 Commercial mortgage-backed 652 10 96 2 748 12 Other asset-backed 552 8 5 — 557 8 Total asset-backed 2,167 27 265 10 2,432 37 U.S. Treasury and obligations of government-sponsored enterprises 4 — — — 4 — Foreign government 54 1 — — 54 1 Redeemable preferred stock 3 — — — 3 — Total fixed maturity securities available-for-sale 7,448 338 502 50 7,950 388 Equity securities available-for-sale: Common stock 3 1 — — 3 1 Preferred stock 13 3 — — 13 3 Total equity securities available-for-sale 16 4 — — 16 4 Total $ 7,464 $ 342 $ 502 $ 50 $ 7,966 $ 392
Activity related to the pretax fixed maturity credit loss component reflected within retained earnings for securities still held for which a portion of an OTTI loss was recognized in OCI	The following table presents the activity related to the pretax credit loss component reflected in Retained earnings on fixed maturity securities still held as of March 31, 2016 and 2015 for which a portion of an OTTI loss was recognized in Other comprehensive income (loss). Three months ended March 31 (In millions) 2016 2015 Beginning balance of credit losses on fixed maturity securities $ 53 $ 62 Additional credit losses for securities for which an OTTI loss was previously recognized — — Reductions for securities sold during the period (5 ) (1 ) Reductions for securities the Company intends to sell or more likely than not will be required to sell — — Ending balance of credit losses on fixed maturity securities $ 48 $ 61
Contractual maturity	The following table presents available-for-sale fixed maturity securities by contractual maturity. March 31, 2016 December 31, 2015 (In millions) Amortized Cost Estimated Fair Value Amortized Cost Estimated Fair Value Due in one year or less $ 1,747 $ 1,773 $ 1,574 $ 1,595 Due after one year through five years 8,335 8,748 7,721 8,070 Due after five years through ten years 14,587 15,129 14,652 14,915 Due after ten years 12,600 14,600 13,303 14,989 Total $ 37,269 $ 40,250 $ 37,250 $ 39,569

Fair Value (Tables)

Fair Value (Tables)	3 Months Ended
	Mar. 31, 2016
Fair Value Disclosures [Abstract]
Assets and liabilities measured at fair value on a recurring basis	Assets and liabilities measured at fair value on a recurring basis are presented in the following tables. March 31, 2016 Total Assets/Liabilities at Fair Value (In millions) Level 1 Level 2 Level 3 Assets Fixed maturity securities: Corporate and other bonds $ — $ 17,916 $ 193 $ 18,109 States, municipalities and political subdivisions — 13,177 2 13,179 Asset-backed: Residential mortgage-backed — 5,078 128 5,206 Commercial mortgage-backed — 2,172 27 2,199 Other asset-backed — 871 50 921 Total asset-backed — 8,121 205 8,326 U.S. Treasury and obligations of government-sponsored enterprises 139 1 — 140 Foreign government — 463 — 463 Redeemable preferred stock 35 — — 35 Total fixed maturity securities 174 39,678 400 40,252 Equity securities 170 — 19 189 Other invested assets — 17 — 17 Short term investments 508 1,064 — 1,572 Life settlement contracts, included in Other assets — — 72 72 Total assets $ 852 $ 40,759 $ 491 $ 42,102 Liabilities Other liabilities $ — $ 1 $ — $ 1 Total liabilities $ — $ 1 $ — $ 1 December 31, 2015 Total Assets/Liabilities at Fair Value (In millions) Level 1 Level 2 Level 3 Assets Fixed maturity securities: Corporate and other bonds $ — $ 17,592 $ 168 $ 17,760 States, municipalities and political subdivisions — 13,172 2 13,174 Asset-backed: Residential mortgage-backed — 4,938 134 5,072 Commercial mortgage-backed — 2,175 22 2,197 Other asset-backed — 868 53 921 Total asset-backed — 7,981 209 8,190 U.S. Treasury and obligations of government-sponsored enterprises 66 1 — 67 Foreign government — 346 — 346 Redeemable preferred stock 35 — — 35 Total fixed maturity securities 101 39,092 379 39,572 Equity securities 177 — 20 197 Other invested assets — 17 — 17 Short term investments 448 1,134 — 1,582 Life settlement contracts, included in Other assets — — 74 74 Total assets $ 726 $ 40,243 $ 473 $ 41,442 Liabilities Other liabilities $ — $ (5 ) $ — $ (5 ) Total liabilities $ — $ (5 ) $ — $ (5 )
Table of reconciliation for assets and liablities measured at fair value on a recurring basis using significant unobservable inputs	The tables below present a reconciliation for all assets and liabilities measured at fair value on a recurring basis using significant unobservable inputs (Level 3). Level 3 (In millions) Balance as of January 1, 2016 Net realized investment gains (losses) and net change in unrealized appreciation (depreciation) included in Net income (loss)* Net change in unrealized appreciation (depreciation) included in Other comprehensive income (loss) Purchases Sales Settlements Transfers into Level 3 Transfers out of Level 3 Balance as of March 31, 2016 Unrealized gains (losses) on Level 3 assets and liabilities held as of March 31, 2016 recognized in Net income (loss)* Fixed maturity securities: Corporate and other bonds $ 168 $ (1 ) $ 4 $ 53 $ (16 ) $ (3 ) $ — $ (12 ) $ 193 $ — States, municipalities and political subdivisions 2 — — — — — — — 2 — Asset-backed: Residential mortgage-backed 134 1 — — — (5 ) — (2 ) 128 — Commercial mortgage-backed 22 — — 9 — — — (4 ) 27 — Other asset-backed 53 — — — — — 2 (5 ) 50 — Total asset-backed 209 1 — 9 — (5 ) 2 (11 ) 205 — Total fixed maturity securities 379 — 4 62 (16 ) (8 ) 2 (23 ) 400 — Equity securities 20 — (1 ) — — — — — 19 — Life settlement contracts 74 4 — — — (6 ) — — 72 1 Total $ 473 $ 4 $ 3 $ 62 $ (16 ) $ (14 ) $ 2 $ (23 ) $ 491 $ 1 Level 3 (In millions) Balance as of January 1, 2015 Net realized investment gains (losses) and net change in unrealized appreciation (depreciation) included in Net income (loss)* Net change in unrealized appreciation (depreciation) included in Other comprehensive income (loss) Purchases Sales Settlements Transfers into Level 3 Transfers out of Level 3 Balance as of March 31, 2015 Unrealized gains (losses) on Level 3 assets and liabilities held as of March 31, 2015 recognized in Net income (loss)* Fixed maturity securities: Corporate and other bonds $ 162 $ 1 $ — $ 12 $ (12 ) $ (14 ) $ 37 $ — $ 186 $ — States, municipalities and political subdivisions 94 1 — — — (9 ) — — 86 — Asset-backed: Residential mortgage-backed 189 1 — 72 — (10 ) — (20 ) 232 — Commercial mortgage-backed 83 1 1 6 — (1 ) — (26 ) 64 — Other asset-backed 655 1 9 35 (144 ) (3 ) — — 553 — Total asset-backed 927 3 10 113 (144 ) (14 ) — (46 ) 849 — Total fixed maturity securities 1,183 5 10 125 (156 ) (37 ) 37 (46 ) 1,121 — Equity securities 16 — (3 ) — — — — — 13 — Life settlement contracts 82 13 — — — (16 ) — — 79 1 Total $ 1,281 $ 18 $ 7 $ 125 $ (156 ) $ (53 ) $ 37 $ (46 ) $ 1,213 $ 1
Quantitative information about significant unobservable inputs in the fair value measurement of level 3 assets	The following tables present quantitative information about the significant unobservable inputs utilized by the Company in the fair value measurements of Level 3 assets. Valuations for assets and liabilities not presented in the tables below are primarily based on broker/dealer quotes for which there is a lack of transparency as to inputs used to develop the valuations. The quantitative detail of these unobservable inputs is neither provided nor reasonably available to the Company. March 31, 2016 Estimated Fair Value (In millions) Valuation Technique(s) Unobservable Input(s) Range (Weighted Average) Fixed maturity securities $ 142 Discounted cash flow Credit spread 0% - 20% (4%) Life settlement contracts 72 Discounted cash flow Discount rate risk premium 9% Mortality assumption 55% - 1676% (164%) December 31, 2015 Estimated Fair Value Valuation Technique(s) Unobservable Input(s) Range (Weighted Average) Fixed maturity securities $ 138 Discounted cash flow Credit spread 3% - 184% (6%) Life settlement contracts 74 Discounted cash flow Discount rate risk premium 9% Mortality assumption 55% - 1676% (164%)
Carrying amount and estimated fair value of financial instrument assets and liabilities not measured at fair value	The carrying amount and estimated fair value of the Company's financial assets and liabilities which are not measured at fair value on the Condensed Consolidated Balance Sheets are presented in the following tables. March 31, 2016 Carrying Amount Estimated Fair Value (In millions) Level 1 Level 2 Level 3 Total Assets Mortgage loans $ 675 $ — $ — $ 697 $ 697 Liabilities Long term debt $ 2,708 $ — $ 2,943 $ — $ 2,943 December 31, 2015 Carrying Estimated Fair Value (In millions) Level 1 Level 2 Level 3 Total Assets Mortgage loans $ 678 $ — $ — $ 688 $ 688 Liabilities Short term debt $ 350 $ — $ 360 $ — $ 360 Long term debt 2,210 — 2,433 — 2,433

Claim and Claim Adjustment Ex21

Claim and Claim Adjustment Expense Reserves (Tables)	3 Months Ended
	Mar. 31, 2016
Liability for Claims and Claims Adjustment Expense [Abstract]
Net prior year development	The following tables and discussion present the net prior year development. Three months ended March 31, 2016 (In millions) Specialty Commercial International Corporate & Other Non-Core Total Pretax (favorable) unfavorable net prior year claim and allocated claim adjustment expense reserve development $ (34 ) $ (14 ) $ (4 ) $ — $ (52 ) Pretax (favorable) unfavorable premium development (11 ) (2 ) (1 ) — (14 ) Total pretax (favorable) unfavorable net prior year development $ (45 ) $ (16 ) $ (5 ) $ — $ (66 ) Three months ended March 31, 2015 (In millions) Specialty Commercial International Corporate & Other Non-Core Total Pretax (favorable) unfavorable net prior year claim and allocated claim adjustment expense reserve development $ 2 $ (5 ) $ (4 ) $ — $ (7 ) Pretax (favorable) unfavorable premium development (6 ) (1 ) 16 — 9 Total pretax (favorable) unfavorable net prior year development $ (4 ) $ (6 ) $ 12 $ — $ 2
Net prior year claim and allocated claim adjustment expense reserve development for Specialty segment	The following table presents further detail of the net prior year claim and allocated claim adjustment expense reserve development (development) recorded for the Specialty segment. Three months ended March 31 (In millions) 2016 2015 Pretax (favorable) unfavorable development: Medical Professional Liability $ (7 ) $ 14 Other Professional Liability and Management Liability (9 ) (3 ) Surety — 1 Warranty 2 — Other (20 ) (10 ) Total pretax (favorable) unfavorable development $ (34 ) $ 2
Net prior year claim and allocated claim adjustment expense reserve development for Commercial segment	The following table presents further detail of the development recorded for the Commercial segment. Three months ended March 31 (In millions) 2016 2015 Pretax (favorable) unfavorable development: Commercial Auto $ (15 ) $ — General Liability (15 ) 4 Workers' Compensation 4 (1 ) Property and Other 12 (8 ) Total pretax (favorable) unfavorable development $ (14 ) $ (5 )
Net prior year claim and allocated claim adjustment expense reserve development for International segment	The following table presents further detail of the development recorded for the International segment. Three months ended March 31 (In millions) 2016 2015 Pretax (favorable) unfavorable development: Medical Professional Liability $ — $ — Other Professional Liability (1 ) — Liability — (5 ) Property & Marine (4 ) (6 ) Other 1 7 Total pretax (favorable) unfavorable development $ (4 ) $ (4 )
Impact Of Loss Portfolio Transfer On Consolidated Statements Of Operations [Table Text Block]	The following table presents the impact of the Loss Portfolio Transfer on the Condensed Consolidated Statements of Operations. Three months ended March 31 (In millions) 2016 2015 Net A&EP adverse development before consideration of LPT $ 200 $ — Provision for uncollectible third-party reinsurance on A&EP — — Additional amounts ceded under LPT 200 — Retroactive reinsurance benefit recognized (73 ) (5 ) Pretax impact of unrecognized deferred retroactive reinsurance benefit $ 127 $ (5 )

Benefit Plans (Tables)

Benefit Plans (Tables)	3 Months Ended
	Mar. 31, 2016
Compensation and Retirement Disclosure [Abstract]
Components of net periodic cost (benefit)	The components of net periodic cost (benefit) are presented in the following table. Three months ended March 31 (In millions) 2016 2015 Pension cost (benefit) Service cost $ — $ 2 Interest cost on projected benefit obligation 28 28 Expected return on plan assets (40 ) (43 ) Amortization of net actuarial loss 9 9 Net periodic pension cost (benefit) $ (3 ) $ (4 )

Accumulated Other Comprehensi23

Accumulated Other Comprehensive Income (Loss) by Component (Tables)	3 Months Ended
	Mar. 31, 2016
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Accumulated Other Comprehensive Income (Loss) by Component	The table below displays the changes in Accumulated other comprehensive income (loss) by component. (In millions) Net unrealized gains (losses) on investments with OTTI losses Net unrealized gains (losses) on other investments Pension and postretirement benefits Cumulative foreign currency translation adjustment Total Balance as of January 1, 2016 $ 27 $ 390 $ (648 ) $ (84 ) $ (315 ) Other comprehensive income (loss) before reclassifications 3 223 — 14 240 Amounts reclassified from accumulated other comprehensive income (loss) net of tax (expense) benefit of $1, $7, $3, $- and $11 (2 ) (11 ) (6 ) — (19 ) Other comprehensive income (loss) net of tax (expense) benefit of $(3), $(116), $(3), $- and $(122) 5 234 6 14 259 Balance as of March 31, 2016 $ 32 $ 624 $ (642 ) $ (70 ) $ (56 ) (In millions) Net unrealized gains (losses) on investments with OTTI losses Net unrealized gains (losses) on other investments Pension and postretirement benefits Cumulative foreign currency translation adjustment Total Balance as of January 1, 2015 $ 36 $ 942 $ (633 ) $ 55 $ 400 Other comprehensive income (loss) before reclassifications (1 ) 121 — (96 ) 24 Amounts reclassified from accumulated other comprehensive income (loss) net of tax (expense) benefit of $-, $-, $3, $- and $3 — 9 (6 ) — 3 Other comprehensive income (loss) net of tax (expense) benefit of $-, $(62), $(3), $- and $(65) (1 ) 112 6 (96 ) 21 Balance as of March 31, 2015 $ 35 $ 1,054 $ (627 ) $ (41 ) $ 421

Business Segments (Tables)

Business Segments (Tables)	3 Months Ended
	Mar. 31, 2016
Segment Reporting [Abstract]
Significant components of the Company's continuing operations and selected balance sheet items	The Company's results of operations and selected balance sheet items by segment are presented in the following tables. Three months ended March 31, 2016 Specialty Commercial International Life & Group Non-Core Corporate & Other Non-Core (In millions) Eliminations Total Operating revenues Net earned premiums $ 682 $ 688 $ 198 $ 131 $ — $ — $ 1,699 Net investment income 107 126 12 187 3 — 435 Other revenues 87 6 1 — 3 — 97 Total operating revenues 876 820 211 318 6 — 2,231 Claims, Benefits and Expenses Net incurred claims and benefits 390 442 121 323 128 — 1,404 Policyholders’ dividends 1 3 — — — — 4 Amortization of deferred acquisition costs 144 116 47 — — — 307 Other insurance related expenses 75 141 28 33 — — 277 Other expenses 75 5 9 3 54 — 146 Total claims, benefits and expenses 685 707 205 359 182 — 2,138 Operating income (loss) before income tax 191 113 6 (41 ) (176 ) — 93 Income tax (expense) benefit on operating income (loss) (64 ) (39 ) — 39 62 — (2 ) Net operating income (loss) 127 74 6 (2 ) (114 ) — 91 Net realized investment gains (losses) (11 ) (18 ) 4 (3 ) (8 ) — (36 ) Income tax (expense) benefit on net realized investment gains (losses) 4 6 (1 ) — 2 — 11 Net realized investment gains (losses), after tax (7 ) (12 ) 3 (3 ) (6 ) — (25 ) Net income (loss) $ 120 $ 62 $ 9 $ (5 ) $ (120 ) $ — $ 66 March 31, 2016 (In millions) Reinsurance receivables $ 765 $ 623 $ 139 $ 496 $ 2,707 $ — $ 4,730 Insurance receivables 884 1,025 276 14 2 — 2,201 Deferred acquisition costs 309 225 88 — — — 622 Goodwill 117 — 33 — — — 150 Insurance reserves Claim and claim adjustment expenses 6,325 9,095 1,395 3,311 2,892 — 23,018 Unearned premiums 1,861 1,347 464 136 — (1 ) 3,807 Future policy benefits — — — 10,500 — — 10,500 Three months ended March 31, 2015 Specialty Commercial International Life & Group Non-Core Corporate & Other Non-Core (In millions) Eliminations Total Operating revenues Net earned premiums $ 680 $ 678 $ 191 $ 138 $ — $ — $ 1,687 Net investment income 155 204 14 179 6 — 558 Other revenues 78 9 — 9 2 (1 ) 97 Total operating revenues 913 891 205 326 8 (1 ) 2,342 Claims, Benefits and Expenses Net incurred claims and benefits 429 454 116 340 (4 ) — 1,335 Policyholders’ dividends 1 3 — — — — 4 Amortization of deferred acquisition costs 144 117 35 7 — — 303 Other insurance related expenses 69 127 37 35 — — 268 Other expenses 67 8 5 4 46 (1 ) 129 Total claims, benefits and expenses 710 709 193 386 42 (1 ) 2,039 Operating income (loss) before income tax 203 182 12 (60 ) (34 ) — 303 Income tax (expense) benefit on operating income (loss) (68 ) (62 ) (3 ) 43 12 — (78 ) Net operating income (loss) 135 120 9 (17 ) (22 ) — 225 Net realized investment gains (losses) 4 4 1 1 — — 10 Income tax (expense) benefit on net realized investment gains (losses) (1 ) (3 ) — 2 — — (2 ) Net realized investment gains (losses), after tax 3 1 1 3 — — 8 Net income (loss) $ 138 $ 121 $ 10 $ (14 ) $ (22 ) $ — $ 233 December 31, 2015 (In millions) Reinsurance receivables $ 724 $ 639 $ 144 $ 497 $ 2,487 $ — $ 4,491 Insurance receivables 890 993 233 11 2 — 2,129 Deferred acquisition costs 307 213 78 — — — 598 Goodwill 117 — 33 — — — 150 Insurance reserves Claim and claim adjustment expenses 6,269 9,183 1,347 3,220 2,644 — 22,663 Unearned premiums 1,839 1,297 415 120 — — 3,671 Future policy benefits — — — 10,152 — — 10,152
Revenues by line of business	The following table presents revenue by line of business for each reportable segment. Revenues are comprised of Operating revenues and Net realized investment gains and losses. Three months ended March 31 (In millions) 2016 2015 Specialty Management & Professional Liability $ 618 $ 697 Surety 127 120 Warranty & Alternative Risks 120 100 Specialty revenues 865 917 Commercial Middle Market 401 409 Small Business 143 165 Other Commercial Insurance 258 321 Commercial revenues 802 895 International Canada 50 55 CNA Europe 78 77 Hardy 87 74 International revenues 215 206 Life & Group Non-Core revenues 315 327 Corporate & Other Non-Core revenues (2 ) 8 Eliminations — (1 ) Total revenues $ 2,195 $ 2,352

General (Narrative) (Details)

General (Narrative) (Details) - USD ($) $ in Millions	Mar. 31, 2016	Dec. 31, 2015
Cumulative Effect of New Accounting Principle in Period of Adoption on Long Term Debt		$ (2)
Cumulative Effect of New Accounting Principle in Period of Adoption on Other Assets		(2)
Other Invested Assets Overseas Deposit	$ 28	$ 27

Earnings Per Share Narrative (D

Earnings Per Share Narrative (Details) - shares shares in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Earnings Per Share [Abstract]
Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements	542	654
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	180	182

Investments (Narrative) (Detail

Investments (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Dec. 31, 2015
Investments [Abstract]
Gains (Losses) on Extinguishment of Debt	$ 8
Reduction of net unrealized gains on investments included in AOCI due to shadow adjustments	1,311	$ 1,111
Fixed maturity securities and equity securities in the energy and metals and mining sectors, at fair value	2,446
Fixed maturity securities and equity securities in the energy and metals and mining sectors, amortized cost or cost basis	2,464
Fixed maturity securities and equity securities in the energy and metals and mining sectors, at fair value, unrealized loss position	1,069
Fixed maturity securities and equity securities in the energy and metals and mining sectors, amortized cost or cost basis, unrealized loss position	1,202
Derivative, Notional Amount	178	179
Derivative Asset, Fair Value, Gross Asset	1
Derivative Liability, Fair Value, Gross Liability		$ (5)
Future Capital Call Commitments	371
Mortgage Loan Commitments	10
Commitments To Purchase Or Fund Additional Amounts	163
Commitments To Sell Various Privately Placed Debt Securities	$ 166

Investments (Net investment inc

Investments (Net investment income) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Net Investment Income [Line Items]
Gross investment income	$ 449	$ 572
Investment expense	(14)	(14)
Net investment income	435	558
Fixed maturity securities [Member]
Net Investment Income [Line Items]
Gross investment income	446	443
Total equity securities available-for-sale [Member]
Net Investment Income [Line Items]
Gross investment income	3	3
Limited partnership investments [Member]
Net Investment Income [Line Items]
Gross investment income	(14)	114
Mortgage loans [Member]
Net Investment Income [Line Items]
Gross investment income	9	8
Short term investments [Member]
Net Investment Income [Line Items]
Gross investment income	3	2
Trading portfolio [Member]
Net Investment Income [Line Items]
Gross investment income	$ 2	$ 2

Investments (Net realized inves

Investments (Net realized investment gains (losses)) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Net realized investment gains (losses)	$ (36)	$ 10
Fixed maturity securities [Member]
Gross realized gains	45	33
Gross realized losses	(62)	(21)
Net realized investment gains (losses)	(17)	12
Total equity securities available-for-sale [Member]
Gross realized gains	0	1
Gross realized losses	(5)	(1)
Net realized investment gains (losses)	(5)	0
Derivative [Member]
Net realized investment gains (losses)	(7)	(1)
Short term investments and other [Member]
Net realized investment gains (losses)	$ (7)	$ (1)

Investments (Components of othe

Investments (Components of other-than-temporary impairment losses recognized in earnings) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Other-than-temporary impairment losses recognized in earnings	$ 23	$ 12
Corporate and other bonds [Member]
Other-than-temporary impairment losses recognized in earnings	16	5
States, municipalities and political subdivisions [Member]
Other-than-temporary impairment losses recognized in earnings	0	5
Residential mortgage-backed [Member]
Other-than-temporary impairment losses recognized in earnings	0	1
Other asset-backed [Member]
Other-than-temporary impairment losses recognized in earnings	2	0
Total asset-backed [Member]
Other-than-temporary impairment losses recognized in earnings	2	1
Total fixed maturity securities available-for-sale [Member]
Other-than-temporary impairment losses recognized in earnings	18	11
Common stock [Member]
Other-than-temporary impairment losses recognized in earnings	5	1
Total equity securities available-for-sale [Member]
Other-than-temporary impairment losses recognized in earnings	$ 5	$ 1

Investments (Summary of fixed m

Investments (Summary of fixed maturity and equity securities) (Details) - USD ($) $ in Millions	Mar. 31, 2016	Dec. 31, 2015
Cost or Amortized Cost	$ 37,453	$ 37,444
Gross Unrealized Gain	3,275	2,717
Gross Unrealized Loss	287	392
Estimated fair value	40,441	39,769
Corporate and other bonds [Member]
Cost or Amortized Cost	17,076	17,080
Gross Unrealized Gain	1,255	1,019
Gross Unrealized Loss	224	342
Estimated fair value	18,107	17,757
Unrealized OTTI Losses (Gains)	0	0
States, municipalities and political subdivisions [Member]
Cost or Amortized Cost	11,478	11,729
Gross Unrealized Gain	1,704	1,453
Gross Unrealized Loss	3	8
Estimated fair value	13,179	13,174
Unrealized OTTI Losses (Gains)	(15)	(4)
Residential mortgage-backed [Member]
Cost or Amortized Cost	5,028	4,935
Gross Unrealized Gain	197	154
Gross Unrealized Loss	19	17
Estimated fair value	5,206	5,072
Unrealized OTTI Losses (Gains)	(33)	(37)
Commercial mortgage-backed [Member]
Cost or Amortized Cost	2,137	2,154
Gross Unrealized Gain	78	55
Gross Unrealized Loss	16	12
Estimated fair value	2,199	2,197
Unrealized OTTI Losses (Gains)	0	0
Other asset-backed [Member]
Cost or Amortized Cost	937	923
Gross Unrealized Gain	4	6
Gross Unrealized Loss	20	8
Estimated fair value	921	921
Unrealized OTTI Losses (Gains)	0	0
Total asset-backed [Member]
Cost or Amortized Cost	8,102	8,012
Gross Unrealized Gain	279	215
Gross Unrealized Loss	55	37
Estimated fair value	8,326	8,190
Unrealized OTTI Losses (Gains)	(33)	(37)
U.S. Treasury and obligations of government-sponsored enterprises [Member]
Cost or Amortized Cost	133	62
Gross Unrealized Gain	7	5
Gross Unrealized Loss	0	0
Estimated fair value	140	67
Unrealized OTTI Losses (Gains)	0	0
Foreign Government Debt Securities [Member]
Cost or Amortized Cost	447	334
Gross Unrealized Gain	17	13
Gross Unrealized Loss	1	1
Estimated fair value	463	346
Unrealized OTTI Losses (Gains)	0	0
Redeemable preferred stock [Member]
Cost or Amortized Cost	33	33
Gross Unrealized Gain	2	2
Gross Unrealized Loss	0	0
Estimated fair value	35	35
Unrealized OTTI Losses (Gains)	0	0
Total fixed maturity securities available-for-sale [Member]
Cost or Amortized Cost	37,269	37,250
Gross Unrealized Gain	3,264	2,707
Gross Unrealized Loss	283	388
Estimated fair value	40,250	39,569
Unrealized OTTI Losses (Gains)	(48)	(41)
Total fixed maturity securities trading [Member]
Cost or Amortized Cost, Trading Securities	2	3
Estimated Fair Value, Trading Securities	2	3
Common stock [Member]
Cost or Amortized Cost	37	46
Gross Unrealized Gain	6	3
Gross Unrealized Loss	2	1
Estimated fair value	41	48
Preferred stock [Member]
Cost or Amortized Cost	145	145
Gross Unrealized Gain	5	7
Gross Unrealized Loss	2	3
Estimated fair value	148	149
Total equity securities available-for-sale [Member]
Cost or Amortized Cost	182	191
Gross Unrealized Gain	11	10
Gross Unrealized Loss	4	4
Estimated fair value	$ 189	$ 197

Investments (Securities in a gr

Investments (Securities in a gross unrealized loss position) (Details) - USD ($) $ in Millions	Mar. 31, 2016	Dec. 31, 2015
Schedule of Available-for-sale Securities [Line Items]
Estimated Fair Value, Less than 12 Months	$ 4,314	$ 7,464
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	227	342
Estimated Fair Value, 12 Months or Longer	604	502
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	60	50
Estimated Fair Value, Total	4,918	7,966
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	287	392
Corporate and other bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Estimated Fair Value, Less than 12 Months	2,669	4,882
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	174	302
Estimated Fair Value, 12 Months or Longer	274	162
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	50	40
Estimated Fair Value, Total	2,943	5,044
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	224	342
States, municipalities and political subdivisions [Member]
Schedule of Available-for-sale Securities [Line Items]
Estimated Fair Value, Less than 12 Months	90	338
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	3	8
Estimated Fair Value, 12 Months or Longer	64	75
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	0	0
Estimated Fair Value, Total	154	413
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	3	8
Residential mortgage-backed [Member]
Schedule of Available-for-sale Securities [Line Items]
Estimated Fair Value, Less than 12 Months	376	963
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	11	9
Estimated Fair Value, 12 Months or Longer	159	164
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	8	8
Estimated Fair Value, Total	535	1,127
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	19	17
Commercial mortgage-backed [Member]
Schedule of Available-for-sale Securities [Line Items]
Estimated Fair Value, Less than 12 Months	505	652
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	14	10
Estimated Fair Value, 12 Months or Longer	102	96
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	2	2
Estimated Fair Value, Total	607	748
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	16	12
Other asset-backed [Member]
Schedule of Available-for-sale Securities [Line Items]
Estimated Fair Value, Less than 12 Months	572	552
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	20	8
Estimated Fair Value, 12 Months or Longer	5	5
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	0	0
Estimated Fair Value, Total	577	557
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	20	8
Total asset-backed [Member]
Schedule of Available-for-sale Securities [Line Items]
Estimated Fair Value, Less than 12 Months	1,453	2,167
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	45	27
Estimated Fair Value, 12 Months or Longer	266	265
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	10	10
Estimated Fair Value, Total	1,719	2,432
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	55	37
U.S. Treasury and obligations of government-sponsored enterprises [Member]
Schedule of Available-for-sale Securities [Line Items]
Estimated Fair Value, Less than 12 Months	23	4
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0	0
Estimated Fair Value, 12 Months or Longer	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	0	0
Estimated Fair Value, Total	23	4
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	0	0
Foreign Government Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Estimated Fair Value, Less than 12 Months	54	54
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	1	1
Estimated Fair Value, 12 Months or Longer	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	0	0
Estimated Fair Value, Total	54	54
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	1	1
Redeemable preferred stock [Member]
Schedule of Available-for-sale Securities [Line Items]
Estimated Fair Value, Less than 12 Months	2	3
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0	0
Estimated Fair Value, 12 Months or Longer	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	0	0
Estimated Fair Value, Total	2	3
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	0	0
Total fixed maturity securities available-for-sale [Member]
Schedule of Available-for-sale Securities [Line Items]
Estimated Fair Value, Less than 12 Months	4,291	7,448
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	223	338
Estimated Fair Value, 12 Months or Longer	604	502
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	60	50
Estimated Fair Value, Total	4,895	7,950
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	283	388
Common stock [Member]
Schedule of Available-for-sale Securities [Line Items]
Estimated Fair Value, Less than 12 Months	6	3
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	2	1
Estimated Fair Value, 12 Months or Longer	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	0	0
Estimated Fair Value, Total	6	3
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	2	1
Preferred stock [Member]
Schedule of Available-for-sale Securities [Line Items]
Estimated Fair Value, Less than 12 Months	17	13
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	2	3
Estimated Fair Value, 12 Months or Longer	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	0	0
Estimated Fair Value, Total	17	13
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	2	3
Total equity securities available-for-sale [Member]
Schedule of Available-for-sale Securities [Line Items]
Estimated Fair Value, Less than 12 Months	23	16
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	4	4
Estimated Fair Value, 12 Months or Longer	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	0	0
Estimated Fair Value, Total	23	16
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	$ 4	$ 4

Investments (Activity related t

Investments (Activity related to the pretax fixed maturity credit loss component reflected within retained earnings for securities still held for which a portion of an OTTI loss was recognized in OCI) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Roll Forward]
Beginning balance of credit losses on fixed maturity securities	$ 53	$ 62
Additional credit losses for securities for which an OTTI loss was previously recognized	0	0
Reductions for securities sold during the period	(5)	(1)
Reductions for securities the Company intends to sell or more likely than not will be required to sell	0	0
Ending balance of credit losses on fixed maturity securities	$ 48	$ 61

Investments (Contractual maturi

Investments (Contractual maturity) (Details) - USD ($) $ in Millions	Mar. 31, 2016	Dec. 31, 2015
Investments [Abstract]
Due in one year or less, cost or amortized cost	$ 1,747	$ 1,574
Due after one year through five years, cost or amortized cost	8,335	7,721
Due after five years through ten years, cost or amortized cost	14,587	14,652
Due after ten years, cost or amortized cost	12,600	13,303
Total Amortized Cost Basis	37,269	37,250
Due in one year or less, estimated fair value	1,773	1,595
Due after one year through five years, estimated fair value	8,748	8,070
Due after five years through ten years, estimated fair value	15,129	14,915
Due after ten years, estimated fair value	14,600	14,989
Total Estimated Fair Value	$ 40,250	$ 39,569

Fair Value (Assets and liabilit

Fair Value (Assets and liabilities measured at fair value on a recurring basis) (Details) - USD ($) $ in Millions	Mar. 31, 2016	Dec. 31, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	$ 42,102	$ 41,442
Fair value of liabilities, measured on a recurring basis	1	(5)
Corporate and other bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	18,109	17,760
States, municipalities and political subdivisions [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	13,179	13,174
Residential mortgage-backed [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	5,206	5,072
Commercial mortgage-backed [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	2,199	2,197
Other asset-backed [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	921	921
Total asset-backed [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	8,326	8,190
U.S. Treasury and obligations of government-sponsored enterprises [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	140	67
Foreign Government Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	463	346
Redeemable preferred stock [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	35	35
Fixed maturity securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	40,252	39,572
Equity securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	189	197
Other invested assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	17	17
Short term investments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	1,572	1,582
Life settlement contracts, included in Other assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	72	74
Embedded Derivative Financial Instruments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of liabilities, measured on a recurring basis	1	(5)
Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	852	726
Fair value of liabilities, measured on a recurring basis	0	0
Level 1 [Member] | Corporate and other bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	0	0
Level 1 [Member] | States, municipalities and political subdivisions [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	0	0
Level 1 [Member] | Residential mortgage-backed [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	0	0
Level 1 [Member] | Commercial mortgage-backed [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	0	0
Level 1 [Member] | Other asset-backed [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	0	0
Level 1 [Member] | Total asset-backed [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	0	0
Level 1 [Member] | U.S. Treasury and obligations of government-sponsored enterprises [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	139	66
Level 1 [Member] | Foreign Government Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	0	0
Level 1 [Member] | Redeemable preferred stock [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	35	35
Level 1 [Member] | Fixed maturity securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	174	101
Level 1 [Member] | Equity securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	170	177
Level 1 [Member] | Other invested assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	0	0
Level 1 [Member] | Short term investments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	508	448
Level 1 [Member] | Life settlement contracts, included in Other assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	0	0
Level 1 [Member] | Embedded Derivative Financial Instruments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of liabilities, measured on a recurring basis	0	0
Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	40,759	40,243
Fair value of liabilities, measured on a recurring basis	1	(5)
Level 2 [Member] | Corporate and other bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	17,916	17,592
Level 2 [Member] | States, municipalities and political subdivisions [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	13,177	13,172
Level 2 [Member] | Residential mortgage-backed [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	5,078	4,938
Level 2 [Member] | Commercial mortgage-backed [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	2,172	2,175
Level 2 [Member] | Other asset-backed [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	871	868
Level 2 [Member] | Total asset-backed [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	8,121	7,981
Level 2 [Member] | U.S. Treasury and obligations of government-sponsored enterprises [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	1	1
Level 2 [Member] | Foreign Government Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	463	346
Level 2 [Member] | Redeemable preferred stock [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	0	0
Level 2 [Member] | Fixed maturity securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	39,678	39,092
Level 2 [Member] | Equity securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	0	0
Level 2 [Member] | Other invested assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	17	17
Level 2 [Member] | Short term investments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	1,064	1,134
Level 2 [Member] | Life settlement contracts, included in Other assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	0	0
Level 2 [Member] | Embedded Derivative Financial Instruments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of liabilities, measured on a recurring basis	1	(5)
Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	491	473
Fair value of liabilities, measured on a recurring basis	0	0
Level 3 [Member] | Corporate and other bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	193	168
Level 3 [Member] | States, municipalities and political subdivisions [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	2	2
Level 3 [Member] | Residential mortgage-backed [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	128	134
Level 3 [Member] | Commercial mortgage-backed [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	27	22
Level 3 [Member] | Other asset-backed [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	50	53
Level 3 [Member] | Total asset-backed [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	205	209
Level 3 [Member] | U.S. Treasury and obligations of government-sponsored enterprises [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	0	0
Level 3 [Member] | Foreign Government Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	0	0
Level 3 [Member] | Redeemable preferred stock [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	0	0
Level 3 [Member] | Fixed maturity securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	400	379
Level 3 [Member] | Equity securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	19	20
Level 3 [Member] | Other invested assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	0	0
Level 3 [Member] | Short term investments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	0	0
Level 3 [Member] | Life settlement contracts, included in Other assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets, measured on a recurring basis	72	74
Level 3 [Member] | Embedded Derivative Financial Instruments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of liabilities, measured on a recurring basis	$ 0	$ 0

Fair Value (Table of reconcilia

Fair Value (Table of reconciliation for assets and liabilities measured at fair value on a recurring basis using significant unobservable inputs) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, Beginning, Assets	$ 473	$ 1,281
Net realized investment gains (losses) and net change in unrealized appreciation (depreciation) included in net income (loss)	4	18
Net change in unrealized appreciation (depreciation) included in other comprehensive income (loss)	3	7
Purchases	62	125
Sales	(16)	(156)
Settlements	(14)	(53)
Transfers into Level 3	2	37
Transfers out of Level 3	(23)	(46)
Balance, Ending, Assets	491	1,213
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	1	1
Corporate and other bonds [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, Beginning, Assets	168	162
Net realized investment gains (losses) and net change in unrealized appreciation (depreciation) included in net income (loss)	(1)	1
Net change in unrealized appreciation (depreciation) included in other comprehensive income (loss)	4	0
Purchases	53	12
Sales	(16)	(12)
Settlements	(3)	(14)
Transfers into Level 3	0	37
Transfers out of Level 3	(12)	0
Balance, Ending, Assets	193	186
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0	0
States, municipalities and political subdivisions [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, Beginning, Assets	2	94
Net realized investment gains (losses) and net change in unrealized appreciation (depreciation) included in net income (loss)	0	1
Net change in unrealized appreciation (depreciation) included in other comprehensive income (loss)	0	0
Purchases	0	0
Sales	0	0
Settlements	0	(9)
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Balance, Ending, Assets	2	86
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0	0
Residential mortgage-backed [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, Beginning, Assets	134	189
Net realized investment gains (losses) and net change in unrealized appreciation (depreciation) included in net income (loss)	1	1
Net change in unrealized appreciation (depreciation) included in other comprehensive income (loss)	0	0
Purchases	0	72
Sales	0	0
Settlements	(5)	(10)
Transfers into Level 3	0	0
Transfers out of Level 3	(2)	(20)
Balance, Ending, Assets	128	232
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0	0
Commercial Mortgage Backed Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, Beginning, Assets	22	83
Net realized investment gains (losses) and net change in unrealized appreciation (depreciation) included in net income (loss)	0	1
Net change in unrealized appreciation (depreciation) included in other comprehensive income (loss)	0	1
Purchases	9	6
Sales	0	0
Settlements	0	(1)
Transfers into Level 3	0	0
Transfers out of Level 3	(4)	(26)
Balance, Ending, Assets	27	64
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0	0
Other asset-backed [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, Beginning, Assets	53	655
Net realized investment gains (losses) and net change in unrealized appreciation (depreciation) included in net income (loss)	0	1
Net change in unrealized appreciation (depreciation) included in other comprehensive income (loss)	0	9
Purchases	0	35
Sales	0	(144)
Settlements	0	(3)
Transfers into Level 3	2	0
Transfers out of Level 3	(5)	0
Balance, Ending, Assets	50	553
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0	0
Total asset-backed [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, Beginning, Assets	209	927
Net realized investment gains (losses) and net change in unrealized appreciation (depreciation) included in net income (loss)	1	3
Net change in unrealized appreciation (depreciation) included in other comprehensive income (loss)	0	10
Purchases	9	113
Sales	0	(144)
Settlements	(5)	(14)
Transfers into Level 3	2	0
Transfers out of Level 3	(11)	(46)
Balance, Ending, Assets	205	849
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0	0
Total Fixed maturity securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, Beginning, Assets	379	1,183
Net realized investment gains (losses) and net change in unrealized appreciation (depreciation) included in net income (loss)	0	5
Net change in unrealized appreciation (depreciation) included in other comprehensive income (loss)	4	10
Purchases	62	125
Sales	(16)	(156)
Settlements	(8)	(37)
Transfers into Level 3	2	37
Transfers out of Level 3	(23)	(46)
Balance, Ending, Assets	400	1,121
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0	0
Equity securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, Beginning, Assets	20	16
Net realized investment gains (losses) and net change in unrealized appreciation (depreciation) included in net income (loss)	0	0
Net change in unrealized appreciation (depreciation) included in other comprehensive income (loss)	(1)	(3)
Purchases	0	0
Sales	0	0
Settlements	0	0
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Balance, Ending, Assets	19	13
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0	0
Life settlement contracts, included in Other assets [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, Beginning, Assets	74	82
Net realized investment gains (losses) and net change in unrealized appreciation (depreciation) included in net income (loss)	4	13
Net change in unrealized appreciation (depreciation) included in other comprehensive income (loss)	0	0
Purchases	0	0
Sales	0	0
Settlements	(6)	(16)
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Balance, Ending, Assets	72	79
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	$ 1	$ 1

Fair Value (Narrative) (Details

Fair Value (Narrative) (Details) - USD ($) $ in Millions	Mar. 31, 2016	Dec. 31, 2015	Mar. 31, 2015
Fair Value Disclosures [Abstract]
Fair Value, Assets, Level 2 to Level 1 Transfers, Amount	$ 0		$ 0
Fair Value, Assets, Level 1 to Level 2 Transfers, Amount	0		$ 0
Other Invested Assets Overseas Deposit	$ 28	$ 27

Fair Value (Quantitative inform

Fair Value (Quantitative information about significant unobservable inputs in the fair value measurement of level 3 assets) (Details) - Income Approach Valuation Technique [Member] - USD ($) $ in Millions	Mar. 31, 2016	Dec. 31, 2015
Fixed maturity securities [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Assets, Fair Value Disclosure	$ 142	$ 138
Fixed maturity securities [Member] | Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Credit Spread	0.00%	3.00%
Fixed maturity securities [Member] | Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Credit Spread	20.00%	184.00%
Fixed maturity securities [Member] | Weighted Average [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Credit Spread	4.00%	6.00%
Life settlement contracts, included in Other assets [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Assets, Fair Value Disclosure	$ 72	$ 74
Life settlement contracts, included in Other assets [Member] | Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Mortality assumption	55.00%	55.00%
Life settlement contracts, included in Other assets [Member] | Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Mortality assumption	1676.00%	1676.00%
Life settlement contracts, included in Other assets [Member] | Weighted Average [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Mortality assumption	164.00%	164.00%
Life settlement contracts, included in Other assets [Member] | Rate [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate risk premium	9.00%	9.00%

Fair Value (Carrying amount and

Fair Value (Carrying amount and estimated fair value of financial instrument assets and liabilities which are not measured at fair value) (Details) - USD ($) $ in Millions	Mar. 31, 2016	Dec. 31, 2015
Financial Assets [Abstract]
Mortgage loans	$ 675	$ 678
Financial Liabilities [Abstract]
Short term debt	0	350
Long term debt	2,708	2,210
Carrying Amount [Member]
Financial Assets [Abstract]
Mortgage loans	675	678
Financial Liabilities [Abstract]
Short term debt		350
Long term debt	2,708	2,210
Estimated Fair Value [Member]
Financial Assets [Abstract]
Mortgage loans	697	688
Financial Liabilities [Abstract]
Short term debt		360
Long term debt	2,943	2,433
Level 1 [Member] | Estimated Fair Value [Member]
Financial Assets [Abstract]
Mortgage loans	0	0
Financial Liabilities [Abstract]
Short term debt		0
Long term debt	0	0
Level 2 [Member] | Estimated Fair Value [Member]
Financial Assets [Abstract]
Mortgage loans	0	0
Financial Liabilities [Abstract]
Short term debt		360
Long term debt	2,943	2,433
Level 3 [Member] | Estimated Fair Value [Member]
Financial Assets [Abstract]
Mortgage loans	697	688
Financial Liabilities [Abstract]
Short term debt		0
Long term debt	$ 0	$ 0

Claim and Claim Adjustment Ex40

Claim and Claim Adjustment Expense Reserves (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		48 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2013	Dec. 31, 2015	Dec. 31, 2010
Catastrophe losses net of reinsurance	$ 36	$ 29
Loss Portfolio Transfer [Member]
Liability for Asbestos and Environmental Claims, Net					$ 1,600
Aggregate limit under AEP Loss Portfolio Transfer					4,000
Claim And Allocated Claim Adjustment Expense Reserves Under Existing Third Party Reinsurance Contracts					1,200
Reinsurance premium paid to NICO under AEP Loss Portfolio Transfer					2,000
Net reinsurance receivables transferrred to NICO under AEP Loss Portfolio Transfer					215
Total consideration paid to NICO under AEP Loss Portfolio Transfer					$ 2,200
Net AEP adverse development before consideration of LPT	200	0	$ 900
Asbestos adverse development	146
Environmental pollution adverse development	54
Retroactive reinsurance benefit recognized	(73)	(5)
Pretax impact of deferred retroactive reinsurance benefit	127	$ (5)
Cumulative amounts ceded under AEP Loss Portfolio Transfer	2,800			$ 2,600
Deferred reinsurance benefit yet to be recognized	368			241
Fair value of collateral trust account established by NICO under AEP Loss Portfolio Transfer	$ 2,700			$ 2,800

Claim and Claim Adjustment Ex41

Claim and Claim Adjustment Expense Reserves (Net prior year development) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Segment Reporting Information [Line Items]
Pretax (favorable) unfavorable net prior year claim and allocated claim adjustment expense reserve development, excluding Life & Group	$ (52)	$ (7)
Pretax (favorable) unfavorable premium development, excluding Life & Group	(14)	9
Total pretax (favorable) unfavorable net prior year development, excluding Life & Group	(66)	2
Specialty [Member]
Segment Reporting Information [Line Items]
Pretax (favorable) unfavorable net prior year claim and allocated claim adjustment expense reserve development, excluding Life & Group	(34)	2
Pretax (favorable) unfavorable premium development, excluding Life & Group	(11)	(6)
Total pretax (favorable) unfavorable net prior year development, excluding Life & Group	(45)	(4)
Commercial [Member]
Segment Reporting Information [Line Items]
Pretax (favorable) unfavorable net prior year claim and allocated claim adjustment expense reserve development, excluding Life & Group	(14)	(5)
Pretax (favorable) unfavorable premium development, excluding Life & Group	(2)	(1)
Total pretax (favorable) unfavorable net prior year development, excluding Life & Group	(16)	(6)
International [Member]
Segment Reporting Information [Line Items]
Pretax (favorable) unfavorable net prior year claim and allocated claim adjustment expense reserve development, excluding Life & Group	(4)	(4)
Pretax (favorable) unfavorable premium development, excluding Life & Group	(1)	16
Total pretax (favorable) unfavorable net prior year development, excluding Life & Group	(5)	12
Corporate and Other [Member]
Segment Reporting Information [Line Items]
Pretax (favorable) unfavorable net prior year claim and allocated claim adjustment expense reserve development, excluding Life & Group	0	0
Pretax (favorable) unfavorable premium development, excluding Life & Group	0	0
Total pretax (favorable) unfavorable net prior year development, excluding Life & Group	$ 0	$ 0

Claim and Claim Adjustment Ex42

Claim and Claim Adjustment Expense Reserves (Net prior year claim and allocated claim adjustment expense reserve development for Specialty segment) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Pretax (favorable) unfavorable net prior year claim and allocated claim adjustment expense reserve development, excluding Life & Group	$ (52)	$ (7)
Specialty [Member]
Medical Professional Liability	(7)	14
Other Professional Liability and Management Liability	(9)	(3)
Surety	0	1
Warranty	2	0
Other	(20)	(10)
Pretax (favorable) unfavorable net prior year claim and allocated claim adjustment expense reserve development, excluding Life & Group	$ (34)	$ 2

Claim and Claim Adjustment Ex43

Claim and Claim Adjustment Expense Reserves (Net prior year claim and allocated claim adjustment expense reserve development for Commercial segment) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Pretax (favorable) unfavorable net prior year claim and allocated claim adjustment expense reserve development, excluding Life & Group	$ (52)	$ (7)
Commercial [Member]
Commercial Auto	(15)	0
General Liability	(15)	4
Workers' Compensation	4	(1)
Property and Other	12	(8)
Pretax (favorable) unfavorable net prior year claim and allocated claim adjustment expense reserve development, excluding Life & Group	$ (14)	$ (5)

Claim and Claim Adjustment Ex44

Claim and Claim Adjustment Expense Reserves Net prior year claim and allocated claim adjustment expense reserve development for International segment (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Pretax (favorable) unfavorable net prior year claim and allocated claim adjustment expense reserve development, excluding Life & Group	$ (52)	$ (7)
International [Member]
Medical Professional Liability	0	0
Other Professional Liability	(1)	0
Liability	0	(5)
Property & Marine	(4)	(6)
Other	1	7
Pretax (favorable) unfavorable net prior year claim and allocated claim adjustment expense reserve development, excluding Life & Group	$ (4)	$ (4)

Claim and Claim Adjustment Ex45

Claim and Claim Adjustment Expense Reserves Impact of Loss Portfolio Transfer on the Consolidated Statement of Operations (Details) - Loss Portfolio Transfer [Member] - USD ($) $ in Millions	3 Months Ended		48 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2013
Net AEP adverse development before consideration of LPT	$ 200	$ 0	$ 900
Provision for uncollectible third-party reinsurance on AEP	0	0
Additional amounts ceded under LPT	200	0
Retroactive reinsurance benefit recognized	(73)	(5)
Pretax impact of deferred retroactive reinsurance benefit	$ 127	$ (5)

Benefit Plans (Components of ne

Benefit Plans (Components of net periodic cost (benefit)) (Details) - Pension Plans, Defined Benefit [Member] - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 0	$ 2
Interest cost on projected benefit obligation	28	28
Expected return on plan assets	(40)	(43)
Amortization of net actuarial (gain) loss	9	9
Net periodic (benefit) cost	$ (3)	$ (4)

Commitments and Contingencies47

Commitments and Contingencies, and Guarantees (Narrative) (Detail) - USD ($) $ in Millions	Mar. 31, 2016	Dec. 31, 2015
Property Lease Guarantee [Member]
Loss Contingencies [Line Items]
Guarantor Obligations, Maximum Exposure, Undiscounted	$ 18
Guarantee and Indemnification [Member]
Loss Contingencies [Line Items]
Guarantor Obligations, Current Carrying Value	5	$ 5
Guarantee agreement [Member]
Loss Contingencies [Line Items]
Guarantor Obligations, Maximum Exposure, Undiscounted	375
Indemnification Agreement [Member]
Loss Contingencies [Line Items]
Guarantor Obligations, Maximum Exposure, Undiscounted	259
Guarantee Obligations [Member]
Loss Contingencies [Line Items]
Guarantor Obligations, Maximum Exposure, Undiscounted	$ 2,000

Accumulated Other Comprehensi48

Accumulated Other Comprehensive Income (Loss) by Component (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income (loss), beginning balance	$ (315)	$ 400
Other comprehensive income (loss), before reclassifications	240	24
Amounts reclassified from accumulated other comprehensive income (loss) after tax (expense) benefit	(19)	3
Other comprehensive income (loss) after tax (expense) benefit	259	21
Accumulated other comprehensive income (loss), ending balance	(56)	421
Reclassification from AOCI, Current Period, Tax	11	3
Tax (expense) benefit on other comprehensive income (loss)	(122)	(65)
Net unrealized gains (losses) on investments with OTTI losses [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income (loss), beginning balance	27	36
Other comprehensive income (loss), before reclassifications	3	(1)
Amounts reclassified from accumulated other comprehensive income (loss) after tax (expense) benefit	(2)	0
Other comprehensive income (loss) after tax (expense) benefit	5	(1)
Accumulated other comprehensive income (loss), ending balance	32	35
Reclassification from AOCI, Current Period, Tax	1	0
Tax (expense) benefit on other comprehensive income (loss)	(3)	0
Accumulated Net Investment Gain (Loss) Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income (loss), beginning balance	390	942
Other comprehensive income (loss), before reclassifications	223	121
Amounts reclassified from accumulated other comprehensive income (loss) after tax (expense) benefit	(11)	9
Other comprehensive income (loss) after tax (expense) benefit	234	112
Accumulated other comprehensive income (loss), ending balance	624	1,054
Reclassification from AOCI, Current Period, Tax	7	0
Tax (expense) benefit on other comprehensive income (loss)	(116)	(62)
Pension and postretirement benefits [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income (loss), beginning balance	(648)	(633)
Other comprehensive income (loss), before reclassifications	0	0
Amounts reclassified from accumulated other comprehensive income (loss) after tax (expense) benefit	(6)	(6)
Other comprehensive income (loss) after tax (expense) benefit	6	6
Accumulated other comprehensive income (loss), ending balance	(642)	(627)
Reclassification from AOCI, Current Period, Tax	3	3
Tax (expense) benefit on other comprehensive income (loss)	(3)	(3)
Cumulative foreign currency translation adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income (loss), beginning balance	(84)	55
Other comprehensive income (loss), before reclassifications	14	(96)
Amounts reclassified from accumulated other comprehensive income (loss) after tax (expense) benefit	0	0
Other comprehensive income (loss) after tax (expense) benefit	14	(96)
Accumulated other comprehensive income (loss), ending balance	(70)	(41)
Reclassification from AOCI, Current Period, Tax	0	0
Tax (expense) benefit on other comprehensive income (loss)	$ 0	$ 0

Business Segments (Income State

Business Segments (Income Statement Information) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Operating Revenues
Net earned premiums	$ 1,699	$ 1,687
Net investment income	435	558
Other revenues	97	97
Total operating revenues	2,231	2,342
Claims, Benefits and Expenses
Net incurred claims and benefits	1,404	1,335
Policyholders' dividends	4	4
Amortization of deferred acquisition costs	307	303
Other insurance related expenses	277	268
Other expenses	146	129
Total claims, benefits and expenses	2,138	2,039
Operating income (loss) before income tax	93	303
Income tax (expense) benefit on operating income (loss)	(2)	(78)
Net operating income (loss)	91	225
Net realized investment gains (losses), pre-tax	(36)	10
Income tax (expense) benefit on net realized investment gains (losses)	11	(2)
Net realized investment gains (losses), after tax	(25)	8
Net Income (Loss)	66	233
Specialty [Member]
Operating Revenues
Net earned premiums	682	680
Net investment income	107	155
Other revenues	87	78
Total operating revenues	876	913
Claims, Benefits and Expenses
Net incurred claims and benefits	390	429
Policyholders' dividends	1	1
Amortization of deferred acquisition costs	144	144
Other insurance related expenses	75	69
Other expenses	75	67
Total claims, benefits and expenses	685	710
Operating income (loss) before income tax	191	203
Income tax (expense) benefit on operating income (loss)	(64)	(68)
Net operating income (loss)	127	135
Net realized investment gains (losses), pre-tax	(11)	4
Income tax (expense) benefit on net realized investment gains (losses)	4	(1)
Net realized investment gains (losses), after tax	(7)	3
Net Income (Loss)	120	138
Commercial [Member]
Operating Revenues
Net earned premiums	688	678
Net investment income	126	204
Other revenues	6	9
Total operating revenues	820	891
Claims, Benefits and Expenses
Net incurred claims and benefits	442	454
Policyholders' dividends	3	3
Amortization of deferred acquisition costs	116	117
Other insurance related expenses	141	127
Other expenses	5	8
Total claims, benefits and expenses	707	709
Operating income (loss) before income tax	113	182
Income tax (expense) benefit on operating income (loss)	(39)	(62)
Net operating income (loss)	74	120
Net realized investment gains (losses), pre-tax	(18)	4
Income tax (expense) benefit on net realized investment gains (losses)	6	(3)
Net realized investment gains (losses), after tax	(12)	1
Net Income (Loss)	62	121
International [Member]
Operating Revenues
Net earned premiums	198	191
Net investment income	12	14
Other revenues	1	0
Total operating revenues	211	205
Claims, Benefits and Expenses
Net incurred claims and benefits	121	116
Policyholders' dividends	0	0
Amortization of deferred acquisition costs	47	35
Other insurance related expenses	28	37
Other expenses	9	5
Total claims, benefits and expenses	205	193
Operating income (loss) before income tax	6	12
Income tax (expense) benefit on operating income (loss)	0	(3)
Net operating income (loss)	6	9
Net realized investment gains (losses), pre-tax	4	1
Income tax (expense) benefit on net realized investment gains (losses)	(1)	0
Net realized investment gains (losses), after tax	3	1
Net Income (Loss)	9	10
Life and Group Non-Core [Member]
Operating Revenues
Net earned premiums	131	138
Net investment income	187	179
Other revenues	0	9
Total operating revenues	318	326
Claims, Benefits and Expenses
Net incurred claims and benefits	323	340
Policyholders' dividends	0	0
Amortization of deferred acquisition costs	0	7
Other insurance related expenses	33	35
Other expenses	3	4
Total claims, benefits and expenses	359	386
Operating income (loss) before income tax	(41)	(60)
Income tax (expense) benefit on operating income (loss)	39	43
Net operating income (loss)	(2)	(17)
Net realized investment gains (losses), pre-tax	(3)	1
Income tax (expense) benefit on net realized investment gains (losses)	0	2
Net realized investment gains (losses), after tax	(3)	3
Net Income (Loss)	(5)	(14)
Corporate and Other Non-Core [Member]
Operating Revenues
Net earned premiums	0	0
Net investment income	3	6
Other revenues	3	2
Total operating revenues	6	8
Claims, Benefits and Expenses
Net incurred claims and benefits	128	(4)
Policyholders' dividends	0	0
Amortization of deferred acquisition costs	0	0
Other insurance related expenses	0	0
Other expenses	54	46
Total claims, benefits and expenses	182	42
Operating income (loss) before income tax	(176)	(34)
Income tax (expense) benefit on operating income (loss)	62	12
Net operating income (loss)	(114)	(22)
Net realized investment gains (losses), pre-tax	(8)	0
Income tax (expense) benefit on net realized investment gains (losses)	2	0
Net realized investment gains (losses), after tax	(6)	0
Net Income (Loss)	(120)	(22)
Eliminations [Member]
Operating Revenues
Net earned premiums	0	0
Net investment income	0	0
Other revenues	0	(1)
Total operating revenues	0	(1)
Claims, Benefits and Expenses
Net incurred claims and benefits	0	0
Policyholders' dividends	0	0
Amortization of deferred acquisition costs	0	0
Other insurance related expenses	0	0
Other expenses	0	(1)
Total claims, benefits and expenses	0	(1)
Operating income (loss) before income tax	0	0
Income tax (expense) benefit on operating income (loss)	0	0
Net operating income (loss)	0	0
Net realized investment gains (losses), pre-tax	0	0
Income tax (expense) benefit on net realized investment gains (losses)	0	0
Net realized investment gains (losses), after tax	0	0
Net Income (Loss)	$ 0	$ 0

Business Segments (Balance Shee

Business Segments (Balance Sheet Information) (Details) - USD ($) $ in Millions	Mar. 31, 2016	Dec. 31, 2015
Segment Reporting Information [Line Items]
Reinsurance receivables	$ 4,730	$ 4,491
Insurance receivables	2,201	2,129
Deferred acquisition costs	622	598
Goodwill	150	150
Insurance reserves
Claim and claim adjustment expenses	23,018	22,663
Unearned premiums	3,807	3,671
Future policy benefits	10,500	10,152
Specialty [Member]
Segment Reporting Information [Line Items]
Reinsurance receivables	765	724
Insurance receivables	884	890
Deferred acquisition costs	309	307
Goodwill	117	117
Insurance reserves
Claim and claim adjustment expenses	6,325	6,269
Unearned premiums	1,861	1,839
Future policy benefits	0	0
Commercial [Member]
Segment Reporting Information [Line Items]
Reinsurance receivables	623	639
Insurance receivables	1,025	993
Deferred acquisition costs	225	213
Goodwill	0	0
Insurance reserves
Claim and claim adjustment expenses	9,095	9,183
Unearned premiums	1,347	1,297
Future policy benefits	0	0
International [Member]
Segment Reporting Information [Line Items]
Reinsurance receivables	139	144
Insurance receivables	276	233
Deferred acquisition costs	88	78
Goodwill	33	33
Insurance reserves
Claim and claim adjustment expenses	1,395	1,347
Unearned premiums	464	415
Future policy benefits	0	0
Life and Group Non-Core [Member]
Segment Reporting Information [Line Items]
Reinsurance receivables	496	497
Insurance receivables	14	11
Deferred acquisition costs	0	0
Goodwill	0	0
Insurance reserves
Claim and claim adjustment expenses	3,311	3,220
Unearned premiums	136	120
Future policy benefits	10,500	10,152
Corporate and Other Non-Core [Member]
Segment Reporting Information [Line Items]
Reinsurance receivables	2,707	2,487
Insurance receivables	2	2
Deferred acquisition costs	0	0
Goodwill	0	0
Insurance reserves
Claim and claim adjustment expenses	2,892	2,644
Unearned premiums	0	0
Future policy benefits	0	0
Eliminations [Member]
Segment Reporting Information [Line Items]
Reinsurance receivables	0	0
Insurance receivables	0	0
Deferred acquisition costs	0	0
Goodwill	0	0
Insurance reserves
Claim and claim adjustment expenses	0	0
Unearned premiums	(1)	0
Future policy benefits	$ 0	$ 0

Business Segments (Revenues by

Business Segments (Revenues by Line of Business) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Revenues	$ 2,195	$ 2,352
Specialty [Domain]
Revenues	865	917
Management & Professional Liability [Member]
Revenues	618	697
Surety [Member]
Revenues	127	120
Warranty & Alternative Risks [Member]
Revenues	120	100
Commercial [Domain]
Revenues	802	895
Middle Markets [Member]
Revenues	401	409
Small Business [Member]
Revenues	143	165
Other Commercial Insurance [Member]
Revenues	258	321
International [Domain]
Revenues	215	206
Canada [Member]
Revenues	50	55
CNA Europe [Member]
Revenues	78	77
Hardy [Member]
Revenues	87	74
Life and Group Non-Core [Member]
Revenues	315	327
Corporate and Other Non-Core [Member]
Revenues	(2)	8
Eliminations [Member]
Revenues	$ 0	$ (1)