| **Life Policy and Investment Contract Reserves (Narrative) (Details) - USD ($)** | 9 Months Ended |              |
|----------------------------------------------------------------------------------|----------------|--------------|
||
| Life policy reserves:                                                            |           |         |
| **Liability for Future Policy Benefit, Activity [Line Items]**                   |           |         |
| Discount Rate Assumption Changes included in Impact of flooring at Cohort Level  | $ 5,000,000    | $ 13,000,000 |
| Life Insurance Segment                                                           |           |         |
| **Liability for Future Policy Benefit, Activity [Line Items]**                   |           |         |
| Liability for Future Policy Benefit, Adverse Development, Expense                | $ 0            |         |

| X                                                                                                                                                                                                                                                                                                                                          |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Discount Rate Assumption Changes included in Impact of flooring at Cohort Level
+ References
No definition available.
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|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of expense for adverse development on liability of future policy benefit from net premium exceeding gross premium.
+ References
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| X                                                                                                                                                            |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------|
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| X                                                                                                                                                       |
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