|**Fair Value**                                                                                               | 6 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           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|**Fair Value Disclosures [Abstract]**                                                                        |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    
|Fair Value                                                                                                   | NoteE. Fair ValueFair value is the price that would be received upon sale of an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date.  The following fair value hierarchy is used in selecting inputs, with the highest priority given to Level 1, as these are the most transparent or reliable.Level 1 - Quoted prices for identical instruments in active markets.Level 2 - Quoted prices for similar instruments in active markets; quoted prices for identical or similar instruments in markets that are not active; and model-derived valuations in which all significant inputs are observable in active markets.Level 3 - Valuations derived from valuation techniques in which one or more significant inputs are not observable.Prices may fall within Level 1, 2 or 3 depending upon the methodologies and inputs used to estimate fair value for each specific security.  Prices are determined by a dedicated group within the Investments and Treasury organization, who ultimately report to the Company's CFO.  This group is responsible for valuation policies and procedures.  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 methodologies and inputs the Company believes market participants would use to value the assets.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 changes in price, period-over-period, are reviewed and challenged with the pricing service or broker based on exception criteria, iv) deep dives, where the Company independently validates detailed information regarding inputs and assumptions for individual securities and v) pricing validation, where prices received are compared to prices independently estimated by the Company.Assets and Liabilities Measured at Fair ValueAssets and liabilities measured at fair value on a recurring basis are summarized below.June 30, 2012TotalAssets/(Liabilities)at Fair Value(In millions)Level 1Level 2Level 3AssetsFixed maturity securities:Corporate and other bonds$—$21,004$488$21,492States, municipalities and political subdivisions—10,3278910,416Asset-backed:Residential mortgage-backed—5,4484435,891Commercial mortgage-backed—1,4031661,569Other asset-backed—6314341,065Total asset-backed—7,4821,0438,525U.S. Treasury and obligations of government-sponsored enterprises14242—184Foreign government120519—639Redeemable preferred stock285627111Total fixed maturity securities29039,4301,64741,367Equity securities1069193290Derivative and other financial instruments, included in Other invested assets——1111Short term investments1,22527141,500Life settlement contracts, included in Other assets——116116Separate account business123553370Total assets$1,633$40,147$1,874$43,654LiabilitiesDerivative financial instruments, included in Other liabilities$—$—$(1)$(1)Total liabilities$—$—$(1)$(1)December 31, 2011TotalAssets/(Liabilities)at Fair Value(In millions)Level 1Level 2Level 3AssetsFixed maturity securities:Corporate and other bonds$—$20,402$482$20,884States, municipalities and political subdivisions—9,6111719,782Asset-backed:Residential mortgage-backed—5,3234525,775Commercial mortgage-backed—1,295591,354Other asset-backed—612343955Total asset-backed—7,2308548,084U.S. Treasury and obligations of government-sponsored enterprises45142—493Foreign government92544—636Redeemable preferred stock553—58Total fixed maturity securities54837,8821,50739,937Equity securities12411367304Derivative and other financial instruments, included in Other invested assets—11112Short term investments1,106508271,641Life settlement contracts, included in Other assets——117117Separate account business2137323417Total assets$1,799$38,877$1,752$42,428LiabilitiesDerivative financial instruments, included in Other liabilities$—$—$(1)$(1)Total liabilities$—$—$(1)$(1)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) for the three months endedJune 30, 2012and2011.Level 3(In millions)Balance atApril 1,2012Net 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)PurchasesSalesSettlementsTransfers intoLevel 3Transfers outof Level 3Balance atJune 30,2012Unrealized gains (losses) on Level 3 assets and liabilities held at June 30, 2012 recognized in net income (loss)*Fixed maturity securities:Corporate and other bonds$486$3$2$68$(27)$(13)$9$(40)$488$—States, municipalities and political subdivisions173—1——(85)——89—Asset-backed:Residential mortgage-backed4471(18)22—(9)——443—Commercial mortgage-backed1052487(12)(4)—(16)166—Other asset-backed3842(1)182(99)(34)——434—Total asset-backed9365(15)291(111)(47)—(16)1,043—Redeemable preferred stock53———(26)———27—Total fixed maturity securities1,6488(12)359(164)(145)9(56)1,647—Equity securities74—1915(15)———93(1)Derivative and other financial instruments, net10———————10—Short term investments———4————4—Life settlement contracts11520———(19)——1163Separate account business4———(1)———3—Total$1,851$28$7$378$(180)$(164)$9$(56)$1,873$2Level 3(In millions)Balance atApril 1,2011Net 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)PurchasesSalesSettlementsTransfers intoLevel 3Transfers outof Level 3Balance atJune 30,2011Unrealized gains (losses) on Level 3 assets and liabilities held at June 30, 2011 recognized in net income (loss)*Fixed maturity securities:Corporate and other bonds$577$(2)$2$304$(30)$(70)$31$—$812$(3)States, municipalities and political subdivisions188—(1)——(8)——179—Asset-backed:Residential mortgage-backed738(13)1250(57)(19)—(24)687(15)Commercial mortgage-backed88—25————95—Other asset-backed4451—127(44)(24)—(14)491—Total asset-backed1,271(12)14182(101)(43)—(38)1,273(15)Total fixed maturity securities2,036(14)15486(131)(121)31(38)2,264(18)Equity securities30(1)—4(2)—5—36(1)Derivative and other financial instruments, net81——————91Short term investments27————(21)——6—Life settlement contracts1276———(4)——1293Separate account business39———(2)———37—Total$2,267$(8)$15$490$(135)$(146)$36$(38)$2,481$(15)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) for the six months endedJune 30, 2012and2011.Level 3(In millions)Balance atJanuary 1,2012Net 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)PurchasesSalesSettlementsTransfers intoLevel 3Transfers outof Level 3Balance atJune 30,2012Unrealized gains (losses) on Level 3 assets and liabilities held at June 30, 2012 recognized in net income (loss)*Fixed maturity securities:Corporate and other bonds$482$6$6$147$(113)$(32)$42$(50)$488$—States, municipalities and political subdivisions171—3——(85)——89—Asset-backed:Residential mortgage-backed4522(22)60—(16)—(33)443—Commercial mortgage-backed5928129(12)(4)—(16)166—Other asset-backed34363358(176)(59)—(41)434—Total asset-backed85410(11)547(188)(79)—(90)1,043—Redeemable preferred stock———53(26)———27—Total fixed maturity securities1,50716(2)747(327)(196)42(140)1,647—Equity securities67—1626(16)———93(3)Derivative and other financial instruments, net10———————10—Short term investments27——16—(39)——4—Life settlement contracts11723———(24)——1163Separate account business23———(20)———3—Total$1,751$39$14$789$(363)$(259)$42$(140)$1,873$—Level 3(In millions)Balance atJanuary 1,2011Net 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)PurchasesSalesSettlementsTransfers intoLevel 3Transfers outof Level 3Balance atJune 30,2011Unrealized gains (losses) on Level 3 assets and liabilities held at June 30, 2011 recognized in net income (loss)*Fixed maturity securities:Corporate and other bonds$624$2$(3)$346$(50)$(97)$40$(50)$812$(3)States, municipalities and political subdivisions266————(87)——179—Asset-backed:Residential mortgage-backed767(12)1497(83)(41)—(55)687(15)Commercial mortgage-backed733185(4)———95—Other asset-backed3595—327(131)(55)—(14)491—Total asset-backed1,199(4)32429(218)(96)—(69)1,273(15)Redeemable preferred stock33(3)—(3)—————Total fixed maturity securities2,092126775(271)(280)40(119)2,264(18)Equity securities26(2)(1)19(11)—5—36(4)Derivative and other financial instruments, net253——(19)———91Short term investments27——12—(23)—(10)6—Life settlement contracts1299———(9)——1293Separate account business41———(4)———37—Total$2,340$11$25$806$(305)$(312)$45$(129)$2,481$(18)* Net realized and unrealized gains and losses shown above are reported in Net income (loss) as follows:Major Category of Assets and LiabilitiesConsolidated Statements of Operations Line ItemsFixed maturity securities available-for-saleNet realized investment gains (losses)Fixed maturity securities tradingNet investment incomeEquity securitiesNet realized investment gains (losses)Derivative financial instruments held in a trading portfolioNet investment incomeDerivative financial instruments not held in a trading portfolio and fair value option financial instrumentsNet realized investment gains (losses)Life settlement contractsOther revenuesSecurities shown in the Level 3 tables on the previous pages may be transferred in or out of Level 3 based on the availability of observable market information used to determine the fair value of the security.  The availability of observable market information varies based on market conditions and trading volume and may cause securities to move in and out of Level 3 from reporting period to reporting period.  There were no transfers between Level 1 and Level 2 during the three or six months endedJune 30, 2012or2011.  The Company's policy is to recognize transfers between levels at the beginning of quarterly reporting periods.Valuation Methodologies and InputsThe 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 SecuritiesFixed maturity securities are valued using methodologies that model information generated by market transactions involving identical or comparable assets, as well as discounted cash flow methodologies.  Common inputs include: prices from recently executed transactions of similar securities, broker/dealer 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.Level 1 securities include highly liquid U.S. and foreign government 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.  Securities are generally 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 tax-exempt auction rate certificates and private placement debt securities.  Fair value of auction rate securities is determined utilizing a pricing model with three primary inputs.  The interest rate and spread inputs are observable from like instruments while the expected call date assumption is unobservable due to the uncertain nature of principal prepayments prior to maturity.  Fair value of private placement debt securities is determined using internal models with inputs that are not market observable.Equity SecuritiesLevel 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, broker/dealer quotes and other pricing models utilizing market observable inputs.  Level 3 securities are priced using internal models with inputs that are not market observable.Derivative and Other Financial InstrumentsExchange traded derivatives, primarily futures, are valued using quoted market prices and are classified within Level 1 of the fair value hierarchy.  Level 2 derivatives primarily include currency forwards valued using observable market forward rates.  Over-the-counter derivatives, principally interest rate swaps, total return swaps, credit default swaps, equity warrants and options, are valued using inputs including broker/dealer quotes and are classified within Level 3 of the valuation hierarchy due to a lack of transparency as to whether these quotes are based on information that is observable in the marketplace.  Other financial instruments consist of Level 3 securities for which the fair value option has been elected which contain embedded derivatives and are priced using either broker/dealer quotes or internal models with inputs that are not market observable.Short Term InvestmentsThe valuation of 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 ContractsThe 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.Separate Account BusinessSeparate account business includes fixed maturity securities, equities and short term investments.  The valuation methodologies and inputs for these asset types have been described above.Significant Unobservable InputsThe table below presents 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 table 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.Fair Value at June 30, 2012Valuation Technique(s)Unobservable Input(s)Range(Weighted Average)Assets(In millions)Fixed maturity securities$122Discounted cash flowExpected call date0.3 - 4.7 years (3.5 years)Spreads off benchmark yields225-325 bps (269 bps)$34Market approachPrivate offering price$97.25 - $100.08 ($99.16)Equity securities$93Market approachPrivate offering price$0.10 - $4,023 per share($268.85 per share)Life settlement contracts$116Discounted cash flowDiscount rate risk premium9%Mortality assumption65% - 928% (185%)For fixed maturity securities, an increase to the expected call date assumption or credit spreads off benchmark yields or decrease in the private offering price would result in a lower fair value measurement.  For equity securities, an increase in the private offering price would result in a higher 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 ValueThe carrying amount and estimated fair value of the Company's financial instrument assets and liabilities which are not measured at fair value on the Condensed Consolidated Balance Sheets are listed in the tables below.June 30, 2012CarryingAmountEstimated Fair Value(In millions)Level 1Level 2Level 3TotalFinancial assetsNotes receivable for the issuance of common stock$21$—$—$21$21Mortgage loans339——352352Financial liabilitiesPremium deposits and annuity contracts$105$—$—$109$109Short term debt83—83—83Long term debt2,526—2,835—2,835December 31, 2011CarryingAmountEstimatedFair Value(In millions)Financial assetsNotes receivable for the issuance of common stock$22$22Mortgage loans234247Financial liabilitiesPremium deposits and annuity contracts$109$114Short term debt8384Long term debt2,5252,679The following methods and assumptions were used to estimate the fair value of these financial assets and liabilities.The fair values of Notes receivable for the issuance of common stock were estimated using discounted cash flows utilizing interest rates currently offered for obligations securitized with similar collateral, adjusted for specific note receivable risk.The fair values of Mortgage loans were based on the present value of the expected future cash flows discounted at the current interest rate for origination of similar quality loans, adjusted for specific loan risk.Premium deposits and annuity contracts were valued based on cash surrender values or estimated fair values of policyholder liabilities, net of amounts ceded related to sold business.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.
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|June 30, 2012                                                                                                |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    
|(In millions)                                                                                                | Level 1                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             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                                                                                                                                                                                                                                                                                                                                                                                        
|Premium deposits and annuity contracts                                                                       | $                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  
|Short term debt                                                                                              | 83                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
|Long term debt                                                                                               | 2,525                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             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