| **Weighted Average Interest Rate for Life Policy Products (Details) - Life policy reserves:** | Sep. 30, 2023 | Sep. 30, 2022 |
|-----------------------------------------------------------------------------------------------|---------------|---------------|
| Term Life Insurance                                                                           |          |          |
| **Liability for Future Policy Benefit, Activity [Line Items]**                                |          |          |
| Interest accretion rate                                                                       | 5.29%         | 5.15%         |
| Current discount rate                                                                         | 5.73%         | 5.18%         |
| Whole Life Insurance                                                                          |          |          |
| **Liability for Future Policy Benefit, Activity [Line Items]**                                |          |          |
| Interest accretion rate                                                                       | 5.92%         | 5.97%         |
| Current discount rate                                                                         | 5.95%         | 5.51%         |

| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - 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.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Current weighted-average discount rate used to measure liability for future policy benefit.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Original weighted-average discount rate at contract issue date used to measure liability for future policy benefit.
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| X                                                                                                                                                |
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| X                                                                                                                                                            |
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| X                                                                                                                                                 |
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