| **Consolidated Statements of Comprehensive Income (Loss) (Unaudited) (USD $)In Millions, unless otherwise specified** | 3 Months Ended | 6 Months Ended |
|-----------------------------------------------------------------------------------------------------------------------|----------------|----------------|
||
| **Changes in:**                                                                                                       |           |           |   |   |
| Net unrealized gains (losses) on investments with other-than-temporary impairments                                    | $ (8)          | $ (3)          | $ 6 | $ 37 |
| Net unrealized gains (losses) on other investments                                                                    | (585)          | 120            | (647) | 337 |
| Net unrealized gains (losses) on investments                                                                          | (593)          | 117            | (641) | 374 |
| Foreign currency translation adjustment                                                                               | (13)           | (17)           | (74) | 4 |
| Pension and postretirement benefits                                                                                   | 5              | 3              | 10 | 9 |
| Other comprehensive income (loss), net of tax                                                                         | (601)          | 103            | (705) | 387 |
| Net income (loss)                                                                                                     | 194            | 166            | 444 | 416 |
| Total comprehensive income (loss)                                                                                     | $ (407)        | $ 269          | $ (261) | $ 803 |

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| - Definition
The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the reporting entity. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, but excludes any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.
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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.
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| - Definition
Net of tax and reclassification adjustments of the change in the balance sheet adjustment that results from the process of translating subsidiary financial statements and foreign equity investments into the reporting currency of the reporting entity. Also includes the following: gain (loss) on foreign currency forward exchange contracts; foreign currency transactions designated as hedges of net investment in a foreign entity and intercompany foreign currency transactions that are of a long-term nature, when the entities to the transaction are consolidated, combined, or accounted for by the equity method in the reporting enterprise's financial statements; and gain (loss) on a derivative instrument or nonderivative financial instrument that may give rise to a foreign currency transaction gain (loss) that has been designated and qualified as a hedging instrument for hedging of the foreign currency exposure of a net investment in a foreign operation.
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|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Net of tax amount of other comprehensive income (loss) attributable to the parent entity.
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Net of tax and reclassifications amount of pension and other postretirement benefit plans (gain) loss included in accumulated other comprehensive income (loss).
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