| **Schedule of Other Intangible Assets (Narrative) (Details) (USD $)In Millions, unless otherwise specified** | 3 Months Ended |
|--------------------------------------------------------------------------------------------------------------|----------------|
||
| Amortization of deferred acquisition costs                                                                   | $ 329          | $ 328 |
| Finite-Lived Intangible Assets, Amortization Expense, Year Two                                               | 1              |   |
| Finite-Lived Intangible Assets, Amortization Expense, Year Three                                             | 2              |   |
| Finite-Lived Intangible Assets, Amortization Expense, Year Four                                              | 2              |   |
| Finite-Lived Intangible Assets, Amortization Expense, Year Five                                              | 2              |   |
| Hardy [Member]                                                                                               |           |   |
| Amortization of deferred acquisition costs                                                                   | 28             | 21 |
| Other Intangible Assets [Member] | Hardy [Member]                                                            |           |   |
| Amortization of deferred acquisition costs                                                                   | 1              | 9 |
| Amortization expense included in other operating expenses                                                    |           | $ 3 |

| X                                                                                                                                                                                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amortization expense included in other operating expenses
+ References
No definition available.
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of expense related to deferred policy acquisition costs.
+ References
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|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
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.
+ References
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|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of amortization expense expected to be recognized during the fourth fiscal year following the latest fiscal year for assets, excluding financial assets and goodwill, lacking physical substance with a finite life.
+ References
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| - Definition
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.
+ References
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|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
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.
+ References
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