| **Investments (Securities in a gross unrealized loss position) (Details) (USD $)In Millions, unless otherwise specified** | Mar. 31, 2015                                                                                                                                                                                                          | Dec. 31, 2014                                                                                                                                                                                                           |
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| **Schedule of Available-for-sale Securities [Line Items]**                                                                |                                                                                                                                                                                                                   |                                                                                                                                                                                                                    |
| Estimated Fair Value, Less than 12 Months                                                                                 | $ 2,030us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue                                                                                                                 | $ 2,855us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue                                                                                                                  |
| Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss                 | 50us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss                                                                                                                    | 70us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss                                                                                                                     |
| Estimated Fair Value, 12 Months or Longer                                                                                 | 455us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue                                                                                                                     | 707us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue                                                                                                                      |
| Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss                 | 25us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss                                                                                                                    | 29us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss                                                                                                                     |
| Estimated Fair Value, Total                                                                                               | 2,485us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue                                                                                                                                       | 3,562us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue                                                                                                                                        |
| Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss                                      | 75us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAccumulatedLoss                                                                                                                                    | 99us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAccumulatedLoss                                                                                                                                     |
| Corporate and other bonds [Member]                                                                                        |                                                                                                                                                                                                                   |                                                                                                                                                                                                                    |
| **Schedule of Available-for-sale Securities [Line Items]**                                                                |                                                                                                                                                                                                                   |                                                                                                                                                                                                                    |
| Estimated Fair Value, Less than 12 Months                                                                                 | 840us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CorporateDebtSecuritiesMember                             | 1,330us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CorporateDebtSecuritiesMember                            |
| Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss                 | 31us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CorporateDebtSecuritiesMember                            | 46us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CorporateDebtSecuritiesMember                             |
| Estimated Fair Value, 12 Months or Longer                                                                                 | 139us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CorporateDebtSecuritiesMember                             | 277us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CorporateDebtSecuritiesMember                              |
| Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss                 | 12us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CorporateDebtSecuritiesMember                            | 15us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CorporateDebtSecuritiesMember                             |
| Estimated Fair Value, Total                                                                                               | 979us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CorporateDebtSecuritiesMember                                                 | 1,607us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CorporateDebtSecuritiesMember                                                |
| Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss                                      | 43us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CorporateDebtSecuritiesMember                                            | 61us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CorporateDebtSecuritiesMember                                             |
| States, municipalities and political subdivisions [Member]                                                                |                                                                                                                                                                                                                   |                                                                                                                                                                                                                    |
| **Schedule of Available-for-sale Securities [Line Items]**                                                                |                                                                                                                                                                                                                   |                                                                                                                                                                                                                    |
| Estimated Fair Value, Less than 12 Months                                                                                 | 479us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_USStatesAndPoliticalSubdivisionsMember                    | 335us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_USStatesAndPoliticalSubdivisionsMember                     |
| Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss                 | 6us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_USStatesAndPoliticalSubdivisionsMember                    | 5us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_USStatesAndPoliticalSubdivisionsMember                     |
| Estimated Fair Value, 12 Months or Longer                                                                                 | 100us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_USStatesAndPoliticalSubdivisionsMember                    | 127us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_USStatesAndPoliticalSubdivisionsMember                     |
| Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss                 | 3us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_USStatesAndPoliticalSubdivisionsMember                    | 3us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_USStatesAndPoliticalSubdivisionsMember                     |
| Estimated Fair Value, Total                                                                                               | 579us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_USStatesAndPoliticalSubdivisionsMember                                        | 462us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_USStatesAndPoliticalSubdivisionsMember                                         |
| Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss                                      | 9us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_USStatesAndPoliticalSubdivisionsMember                                    | 8us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_USStatesAndPoliticalSubdivisionsMember                                     |
| Residential mortgage-backed [Member]                                                                                      |                                                                                                                                                                                                                   |                                                                                                                                                                                                                    |
| **Schedule of Available-for-sale Securities [Line Items]**                                                                |                                                                                                                                                                                                                   |                                                                                                                                                                                                                    |
| Estimated Fair Value, Less than 12 Months                                                                                 | 318us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_ResidentialMortgageBackedSecuritiesMember                 | 293us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_ResidentialMortgageBackedSecuritiesMember                  |
| Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss                 | 5us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_ResidentialMortgageBackedSecuritiesMember                 | 5us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_ResidentialMortgageBackedSecuritiesMember                  |
| Estimated Fair Value, 12 Months or Longer                                                                                 | 148us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_ResidentialMortgageBackedSecuritiesMember                 | 189us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_ResidentialMortgageBackedSecuritiesMember                  |
| Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss                 | 8us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_ResidentialMortgageBackedSecuritiesMember                 | 8us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_ResidentialMortgageBackedSecuritiesMember                  |
| Estimated Fair Value, Total                                                                                               | 466us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_ResidentialMortgageBackedSecuritiesMember                                     | 482us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_ResidentialMortgageBackedSecuritiesMember                                      |
| Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss                                      | 13us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_ResidentialMortgageBackedSecuritiesMember                                | 13us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_ResidentialMortgageBackedSecuritiesMember                                 |
| Commercial mortgage-backed [Member]                                                                                       |                                                                                                                                                                                                                   |                                                                                                                                                                                                                    |
| **Schedule of Available-for-sale Securities [Line Items]**                                                                |                                                                                                                                                                                                                   |                                                                                                                                                                                                                    |
| Estimated Fair Value, Less than 12 Months                                                                                 | 175us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CommercialMortgageBackedSecuritiesMember                  | 264us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CommercialMortgageBackedSecuritiesMember                   |
| Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss                 | 3us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CommercialMortgageBackedSecuritiesMember                  | 2us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CommercialMortgageBackedSecuritiesMember                   |
| Estimated Fair Value, 12 Months or Longer                                                                                 | 62us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CommercialMortgageBackedSecuritiesMember                   | 99us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CommercialMortgageBackedSecuritiesMember                    |
| Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss                 | 2us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CommercialMortgageBackedSecuritiesMember                  | 3us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CommercialMortgageBackedSecuritiesMember                   |
| Estimated Fair Value, Total                                                                                               | 237us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CommercialMortgageBackedSecuritiesMember                                      | 363us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CommercialMortgageBackedSecuritiesMember                                       |
| Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss                                      | 5us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CommercialMortgageBackedSecuritiesMember                                  | 5us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CommercialMortgageBackedSecuritiesMember                                   |
| Other asset-backed [Member]                                                                                               |                                                                                                                                                                                                                   |                                                                                                                                                                                                                    |
| **Schedule of Available-for-sale Securities [Line Items]**                                                                |                                                                                                                                                                                                                   |                                                                                                                                                                                                                    |
| Estimated Fair Value, Less than 12 Months                                                                                 | 187us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_AssetBackedSecuritiesSecuritizedLoansAndReceivablesMember | 607us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_AssetBackedSecuritiesSecuritizedLoansAndReceivablesMember  |
| Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss                 | 1us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_AssetBackedSecuritiesSecuritizedLoansAndReceivablesMember | 10us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_AssetBackedSecuritiesSecuritizedLoansAndReceivablesMember |
| Estimated Fair Value, 12 Months or Longer                                                                                 | 5us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_AssetBackedSecuritiesSecuritizedLoansAndReceivablesMember   | 7us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_AssetBackedSecuritiesSecuritizedLoansAndReceivablesMember    |
| Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss                 | 0us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_AssetBackedSecuritiesSecuritizedLoansAndReceivablesMember | 0us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_AssetBackedSecuritiesSecuritizedLoansAndReceivablesMember  |
| Estimated Fair Value, Total                                                                                               | 192us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_AssetBackedSecuritiesSecuritizedLoansAndReceivablesMember                     | 614us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_AssetBackedSecuritiesSecuritizedLoansAndReceivablesMember                      |
| Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss                                      | 1us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_AssetBackedSecuritiesSecuritizedLoansAndReceivablesMember                 | 10us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_AssetBackedSecuritiesSecuritizedLoansAndReceivablesMember                 |
| Total asset-backed [Member]                                                                                               |                                                                                                                                                                                                                   |                                                                                                                                                                                                                    |
| **Schedule of Available-for-sale Securities [Line Items]**                                                                |                                                                                                                                                                                                                   |                                                                                                                                                                                                                    |
| Estimated Fair Value, Less than 12 Months                                                                                 | 680us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_AssetBackedSecuritiesMember                               | 1,164us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_AssetBackedSecuritiesMember                              |
| Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss                 | 9us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_AssetBackedSecuritiesMember                               | 17us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_AssetBackedSecuritiesMember                               |
| Estimated Fair Value, 12 Months or Longer                                                                                 | 215us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_AssetBackedSecuritiesMember                               | 295us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_AssetBackedSecuritiesMember                                |
| Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss                 | 10us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_AssetBackedSecuritiesMember                              | 11us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_AssetBackedSecuritiesMember                               |
| Estimated Fair Value, Total                                                                                               | 895us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_AssetBackedSecuritiesMember                                                   | 1,459us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_AssetBackedSecuritiesMember                                                  |
| Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss                                      | 19us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_AssetBackedSecuritiesMember                                              | 28us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_AssetBackedSecuritiesMember                                               |
| U.S. Treasury and obligations of government-sponsored enterprises [Member]                                                |                                                                                                                                                                                                                   |                                                                                                                                                                                                                    |
| **Schedule of Available-for-sale Securities [Line Items]**                                                                |                                                                                                                                                                                                                   |                                                                                                                                                                                                                    |
| Estimated Fair Value, Less than 12 Months                                                                                 | 3us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_USTreasuryAndGovernmentMember                               | 3us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_USTreasuryAndGovernmentMember                                |
| Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss                 | 0us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_USTreasuryAndGovernmentMember                             | 0us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_USTreasuryAndGovernmentMember                              |
| Estimated Fair Value, 12 Months or Longer                                                                                 | 0us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_USTreasuryAndGovernmentMember                               | 4us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_USTreasuryAndGovernmentMember                                |
| Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss                 | 0us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_USTreasuryAndGovernmentMember                             | 0us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_USTreasuryAndGovernmentMember                              |
| Estimated Fair Value, Total                                                                                               | 3us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_USTreasuryAndGovernmentMember                                                   | 7us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_USTreasuryAndGovernmentMember                                                    |
| Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss                                      | 0us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_USTreasuryAndGovernmentMember                                             | 0us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_USTreasuryAndGovernmentMember                                              |
| Foreign Government Debt Securities [Member]                                                                               |                                                                                                                                                                                                                   |                                                                                                                                                                                                                    |
| **Schedule of Available-for-sale Securities [Line Items]**                                                                |                                                                                                                                                                                                                   |                                                                                                                                                                                                                    |
| Estimated Fair Value, Less than 12 Months                                                                                 | 13us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_ForeignGovernmentDebtSecuritiesMember                      | 3us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_ForeignGovernmentDebtSecuritiesMember                        |
| Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss                 | 0us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_ForeignGovernmentDebtSecuritiesMember                     | 0us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_ForeignGovernmentDebtSecuritiesMember                      |
| Estimated Fair Value, 12 Months or Longer                                                                                 | 1us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_ForeignGovernmentDebtSecuritiesMember                       | 3us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_ForeignGovernmentDebtSecuritiesMember                        |
| Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss                 | 0us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_ForeignGovernmentDebtSecuritiesMember                     | 0us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_ForeignGovernmentDebtSecuritiesMember                      |
| Estimated Fair Value, Total                                                                                               | 14us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_ForeignGovernmentDebtSecuritiesMember                                          | 6us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_ForeignGovernmentDebtSecuritiesMember                                            |
| Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss                                      | 0us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_ForeignGovernmentDebtSecuritiesMember                                     | 0us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_ForeignGovernmentDebtSecuritiesMember                                      |
| Redeemable preferred stock [Member]                                                                                       |                                                                                                                                                                                                                   |                                                                                                                                                                                                                    |
| **Schedule of Available-for-sale Securities [Line Items]**                                                                |                                                                                                                                                                                                                   |                                                                                                                                                                                                                    |
| Estimated Fair Value, Less than 12 Months                                                                                 |                                                                                                                                                                                                                   | 3us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_RedeemablePreferredStockMember                               |
| Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss                 |                                                                                                                                                                                                                   | 0us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_RedeemablePreferredStockMember                             |
| Estimated Fair Value, 12 Months or Longer                                                                                 |                                                                                                                                                                                                                   | 0us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_RedeemablePreferredStockMember                               |
| Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss                 |                                                                                                                                                                                                                   | 0us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_RedeemablePreferredStockMember                             |
| Estimated Fair Value, Total                                                                                               |                                                                                                                                                                                                                   | 3us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_RedeemablePreferredStockMember                                                   |
| Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss                                      |                                                                                                                                                                                                                   | 0us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_RedeemablePreferredStockMember                                             |
| Total fixed maturity securities available-for-sale [Member]                                                               |                                                                                                                                                                                                                   |                                                                                                                                                                                                                    |
| **Schedule of Available-for-sale Securities [Line Items]**                                                                |                                                                                                                                                                                                                   |                                                                                                                                                                                                                    |
| Estimated Fair Value, Less than 12 Months                                                                                 | 2,015us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_FixedIncomeSecuritiesMember                             | 2,838us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_FixedIncomeSecuritiesMember                              |
| Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss                 | 46us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_FixedIncomeSecuritiesMember                              | 68us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_FixedIncomeSecuritiesMember                               |
| Estimated Fair Value, 12 Months or Longer                                                                                 | 455us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_FixedIncomeSecuritiesMember                               | 706us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_FixedIncomeSecuritiesMember                                |
| Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss                 | 25us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_FixedIncomeSecuritiesMember                              | 29us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_FixedIncomeSecuritiesMember                               |
| Estimated Fair Value, Total                                                                                               | 2,470us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_FixedIncomeSecuritiesMember                                                 | 3,544us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_FixedIncomeSecuritiesMember                                                  |
| Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss                                      | 71us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_FixedIncomeSecuritiesMember                                              | 97us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_FixedIncomeSecuritiesMember                                               |
| Preferred stock [Member]                                                                                                  |                                                                                                                                                                                                                   |                                                                                                                                                                                                                    |
| **Schedule of Available-for-sale Securities [Line Items]**                                                                |                                                                                                                                                                                                                   |                                                                                                                                                                                                                    |
| Estimated Fair Value, Less than 12 Months                                                                                 | 15us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_PreferredStockMember                                       | 17us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_PreferredStockMember                                        |
| Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss                 | 4us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_PreferredStockMember                                      | 2us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_PreferredStockMember                                       |
| Estimated Fair Value, 12 Months or Longer                                                                                 | 0us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_PreferredStockMember                                        | 1us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_PreferredStockMember                                         |
| Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss                 | 0us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_PreferredStockMember                                      | 0us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_PreferredStockMember                                       |
| Estimated Fair Value, Total                                                                                               | 15us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_PreferredStockMember                                                           | 18us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_PreferredStockMember                                                            |
| Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss                                      | $ 4us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_PreferredStockMember                                                    | $ 2us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAccumulatedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_PreferredStockMember                                                     |

| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale that have been in a continuous loss position for twelve months or longer.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27337-111563Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale in a continuous loss position.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27337-111563Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
This item represents the aggregate fair value of investments in debt and equity securities in an unrealized loss position which are categorized neither as held-to-maturity nor trading securities.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale that have been in a continuous loss position for less than twelve months.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27337-111563Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
This item represents the aggregate fair value of investments in debt and equity securities categorized neither as held-to-maturity nor trading securities that have been in a continuous unrealized loss position for less than twelve months.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27337-111563Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
This item represents the aggregate fair value of investments in debt and equity securities categorized neither as held-to-maturity nor trading securities that have been in a continuous unrealized loss position for twelve months or longer.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27337-111563Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563
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