| **Other Intangible Assets Schedule of Other Intangible Assets (Narrative) (Details) (USD $)In Millions, unless otherwise specified** | 3 Months Ended | 9 Months Ended |
|--------------------------------------------------------------------------------------------------------------------------------------|----------------|----------------|
||
| Amortization of deferred acquisition costs                                                                                           | $ 341          | $ 333          | $ 1,004 | $ 937 |
| Finite-Lived Intangible Assets, Amortization Expense, Remainder of Fiscal Year                                                       | 1              |           | 1 |   |
| Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months                                                             | 4              |           | 4 |   |
| Finite-Lived Intangible Assets, Amortization Expense, Year Two                                                                       | 1              |           | 1 |   |
| Finite-Lived Intangible Assets, Amortization Expense, Year Three                                                                     | 2              |           | 2 |   |
| Finite-Lived Intangible Assets, Amortization Expense, Year Four                                                                      | 2              |           | 2 |   |
| Finite-Lived Intangible Assets, Amortization Expense, Year Five                                                                      | 2              |           | 2 |   |
| Hardy [Member]                                                                                                                       |           |           |   |   |
| Amortization of deferred acquisition costs                                                                                           | 25             | 20             | 66 | 20 |
| Other Intangible Assets [Member] | Hardy [Member]                                                                                    |           |           |   |   |
| Amortization of deferred acquisition costs                                                                                           | 1              | 18             | 14 | 18 |
| Amortization expense included in other operating expenses                                                                            | $ (1)          | $ 6            | $ 4 | $ 6 |

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|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
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|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of deferred policy acquisition costs charged to expense in the period, generally in proportion to related revenue earned, estimated gross profits, or over the customer relationship or some other period.
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Amount of amortization expense expected to be recognized during the next fiscal year following the latest fiscal year for assets, excluding financial assets and goodwill, lacking physical substance with a finite life.
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Amount of amortization expense expected to be recognized during the fifth fiscal year following the latest fiscal year for assets, excluding financial assets and goodwill, lacking physical substance with a finite life.
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Amount of amortization expense expected to be recognized during the third fiscal year following the latest fiscal year for assets, excluding financial assets and goodwill, lacking physical substance with a finite life.
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Amount of amortization expense expected to be recognized during the second fiscal year following the latest fiscal year for assets, excluding financial assets and goodwill, lacking physical substance with a finite life.
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