| **Account Values by Range of Guaranteed Minimum Crediting Rates (Details) - Investment contract reserves: - USD ($) $ in Millions**                                                                                    | Sep. 30, 2023 | Jun. 30, 2023 | Dec. 31, 2022 | Sep. 30, 2022 | Jun. 30, 2022 |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|---------------|---------------|---------------|---------------|---------------|
| Deferred Fixed Annuity                                                                                                                                                                                                 |          |          |          |          |          |
| **Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]**                                                                                                                                       |          |          |          |          |          |
| Balance, end of period                                                                                                                                                                                                 | $ 680         | $ 696         | $ 734         | $ 752         | $ 755         |
| Deferred Fixed Annuity | Policyholder Account Balance, at Guaranteed Minimum Crediting Rate                                                                                                                            |          |          |          |          |          |
| **Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]**                                                                                                                                       |          |          |          |          |          |
| Balance, end of period                                                                                                                                                                                                 | 55            |          |          | 518           |          |
| Deferred Fixed Annuity | Policyholder Account Balance, above Guaranteed Minimum Crediting Rate, Range from 0001 to 0050                                                                                                |          |          |          |          |          |
| **Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]**                                                                                                                                       |          |          |          |          |          |
| Balance, end of period                                                                                                                                                                                                 | 380           |          |          | 0             |          |
| Deferred Fixed Annuity | Policyholder Account Balance, above Guaranteed Minimum Crediting Rate, Range from 0051 to 0150                                                                                                |          |          |          |          |          |
| **Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]**                                                                                                                                       |          |          |          |          |          |
| Balance, end of period                                                                                                                                                                                                 | 16            |          |          | 170           |          |
| Deferred Fixed Annuity | Policyholder Account Balance, above Guaranteed Minimum Crediting Rate, Range from 0151 and Greater                                                                                            |          |          |          |          |          |
| **Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]**                                                                                                                                       |          |          |          |          |          |
| Balance, end of period                                                                                                                                                                                                 | 229           |          |          | 64            |          |
| Deferred Fixed Annuity | Policyholder Account Balance, Guaranteed Minimum Crediting Rate, Range from 0200 to 0299                                                                                                      |          |          |          |          |          |
| **Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]**                                                                                                                                       |          |          |          |          |          |
| Balance, end of period                                                                                                                                                                                                 | 630           |          |          | 701           |          |
| Deferred Fixed Annuity | Policyholder Account Balance, Guaranteed Minimum Crediting Rate, Range from 0200 to 0299 | Policyholder Account Balance, at Guaranteed Minimum Crediting Rate                                 |          |          |          |          |          |
| **Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]**                                                                                                                                       |          |          |          |          |          |
| Balance, end of period                                                                                                                                                                                                 | 5             |          |          | 467           |          |
| Deferred Fixed Annuity | Policyholder Account Balance, Guaranteed Minimum Crediting Rate, Range from 0200 to 0299 | Policyholder Account Balance, above Guaranteed Minimum Crediting Rate, Range from 0001 to 0050     |          |          |          |          |          |
| **Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]**                                                                                                                                       |          |          |          |          |          |
| Balance, end of period                                                                                                                                                                                                 | 380           |          |          | 0             |          |
| Deferred Fixed Annuity | Policyholder Account Balance, Guaranteed Minimum Crediting Rate, Range from 0200 to 0299 | Policyholder Account Balance, above Guaranteed Minimum Crediting Rate, Range from 0051 to 0150     |          |          |          |          |          |
| **Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]**                                                                                                                                       |          |          |          |          |          |
| Balance, end of period                                                                                                                                                                                                 | 16            |          |          | 170           |          |
| Deferred Fixed Annuity | Policyholder Account Balance, Guaranteed Minimum Crediting Rate, Range from 0200 to 0299 | Policyholder Account Balance, above Guaranteed Minimum Crediting Rate, Range from 0151 and Greater |          |          |          |          |          |
| **Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]**                                                                                                                                       |          |          |          |          |          |
| Balance, end of period                                                                                                                                                                                                 | 229           |          |          | 64            |          |
| Deferred Fixed Annuity | Policyholder Account Balance, Guaranteed Minimum Crediting Rate, Range from 0300 to 0399                                                                                                      |          |          |          |          |          |
| **Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]**                                                                                                                                       |          |          |          |          |          |
| Balance, end of period                                                                                                                                                                                                 | 50            |          |          | 51            |          |
| Deferred Fixed Annuity | Policyholder Account Balance, Guaranteed Minimum Crediting Rate, Range from 0300 to 0399 | Policyholder Account Balance, at Guaranteed Minimum Crediting Rate                                 |          |          |          |          |          |
| **Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]**                                                                                                                                       |          |          |          |          |          |
| Balance, end of period                                                                                                                                                                                                 | 50            |          |          | 51            |          |
| Deferred Fixed Annuity | Policyholder Account Balance, Guaranteed Minimum Crediting Rate, Range from 0300 to 0399 | Policyholder Account Balance, above Guaranteed Minimum Crediting Rate, Range from 0001 to 0050     |          |          |          |          |          |
| **Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]**                                                                                                                                       |          |          |          |          |          |
| Balance, end of period                                                                                                                                                                                                 | 0             |          |          | 0             |          |
| Deferred Fixed Annuity | Policyholder Account Balance, Guaranteed Minimum Crediting Rate, Range from 0300 to 0399 | Policyholder Account Balance, above Guaranteed Minimum Crediting Rate, Range from 0051 to 0150     |          |          |          |          |          |
| **Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]**                                                                                                                                       |          |          |          |          |          |
| Balance, end of period                                                                                                                                                                                                 | 0             |          |          | 0             |          |
| Deferred Fixed Annuity | Policyholder Account Balance, Guaranteed Minimum Crediting Rate, Range from 0300 to 0399 | Policyholder Account Balance, above Guaranteed Minimum Crediting Rate, Range from 0151 and Greater |          |          |          |          |          |
| **Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]**                                                                                                                                       |          |          |          |          |          |
| Balance, end of period                                                                                                                                                                                                 | 0             |          |          | 0             |          |
| Universal life                                                                                                                                                                                                         |          |          |          |          |          |
| **Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]**                                                                                                                                       |          |          |          |          |          |
| Balance, end of period                                                                                                                                                                                                 | 456           | $ 456         | $ 457         | 455           | $ 457         |
| Universal life | Policyholder Account Balance, at Guaranteed Minimum Crediting Rate                                                                                                                                    |          |          |          |          |          |
| **Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]**                                                                                                                                       |          |          |          |          |          |
| Balance, end of period                                                                                                                                                                                                 | 396           |          |          | 399           |          |
| Universal life | Policyholder Account Balance, above Guaranteed Minimum Crediting Rate, Range from 0001 to 0050                                                                                                        |          |          |          |          |          |
| **Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]**                                                                                                                                       |          |          |          |          |          |
| Balance, end of period                                                                                                                                                                                                 | 0             |          |          | 46            |          |
| Universal life | Policyholder Account Balance, above Guaranteed Minimum Crediting Rate, Range from 0051 to 0150                                                                                                        |          |          |          |          |          |
| **Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]**                                                                                                                                       |          |          |          |          |          |
| Balance, end of period                                                                                                                                                                                                 | 57            |          |          | 8             |          |
| Universal life | Policyholder Account Balance, above Guaranteed Minimum Crediting Rate, Range from 0151 and Greater                                                                                                    |          |          |          |          |          |
| **Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]**                                                                                                                                       |          |          |          |          |          |
| Balance, end of period                                                                                                                                                                                                 | 3             |          |          | 2             |          |
| Universal life | Policyholder Account Balance, Guaranteed Minimum Crediting Rate, Range from 0200 to 0299                                                                                                              |          |          |          |          |          |
| **Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]**                                                                                                                                       |          |          |          |          |          |
| Balance, end of period                                                                                                                                                                                                 | 120           |          |          | 115           |          |
| Universal life | Policyholder Account Balance, Guaranteed Minimum Crediting Rate, Range from 0200 to 0299 | Policyholder Account Balance, at Guaranteed Minimum Crediting Rate                                         |          |          |          |          |          |
| **Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]**                                                                                                                                       |          |          |          |          |          |
| Balance, end of period                                                                                                                                                                                                 | 60            |          |          | 59            |          |
| Universal life | Policyholder Account Balance, Guaranteed Minimum Crediting Rate, Range from 0200 to 0299 | Policyholder Account Balance, above Guaranteed Minimum Crediting Rate, Range from 0001 to 0050             |          |          |          |          |          |
| **Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]**                                                                                                                                       |          |          |          |          |          |
| Balance, end of period                                                                                                                                                                                                 | 0             |          |          | 46            |          |
| Universal life | Policyholder Account Balance, Guaranteed Minimum Crediting Rate, Range from 0200 to 0299 | Policyholder Account Balance, above Guaranteed Minimum Crediting Rate, Range from 0051 to 0150             |          |          |          |          |          |
| **Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]**                                                                                                                                       |          |          |          |          |          |
| Balance, end of period                                                                                                                                                                                                 | 57            |          |          | 8             |          |
| Universal life | Policyholder Account Balance, Guaranteed Minimum Crediting Rate, Range from 0200 to 0299 | Policyholder Account Balance, above Guaranteed Minimum Crediting Rate, Range from 0151 and Greater         |          |          |          |          |          |
| **Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]**                                                                                                                                       |          |          |          |          |          |
| Balance, end of period                                                                                                                                                                                                 | 3             |          |          | 2             |          |
| Universal life | Policyholder Account Balance, Guaranteed Minimum Crediting Rate, Range from 0300 to 0399                                                                                                              |          |          |          |          |          |
| **Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]**                                                                                                                                       |          |          |          |          |          |
| Balance, end of period                                                                                                                                                                                                 | 54            |          |          | 52            |          |
| Universal life | Policyholder Account Balance, Guaranteed Minimum Crediting Rate, Range from 0300 to 0399 | Policyholder Account Balance, at Guaranteed Minimum Crediting Rate                                         |          |          |          |          |          |
| **Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]**                                                                                                                                       |          |          |          |          |          |
| Balance, end of period                                                                                                                                                                                                 | 54            |          |          | 52            |          |
| Universal life | Policyholder Account Balance, Guaranteed Minimum Crediting Rate, Range from 0300 to 0399 | Policyholder Account Balance, above Guaranteed Minimum Crediting Rate, Range from 0001 to 0050             |          |          |          |          |          |
| **Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]**                                                                                                                                       |          |          |          |          |          |
| Balance, end of period                                                                                                                                                                                                 | 0             |          |          | 0             |          |
| Universal life | Policyholder Account Balance, Guaranteed Minimum Crediting Rate, Range from 0300 to 0399 | Policyholder Account Balance, above Guaranteed Minimum Crediting Rate, Range from 0051 to 0150             |          |          |          |          |          |
| **Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]**                                                                                                                                       |          |          |          |          |          |
| Balance, end of period                                                                                                                                                                                                 | 0             |          |          | 0             |          |
| Universal life | Policyholder Account Balance, Guaranteed Minimum Crediting Rate, Range from 0300 to 0399 | Policyholder Account Balance, above Guaranteed Minimum Crediting Rate, Range from 0151 and Greater         |          |          |          |          |          |
| **Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]**                                                                                                                                       |          |          |          |          |          |
| Balance, end of period                                                                                                                                                                                                 | 0             |          |          | 0             |          |
| Universal life | Policyholder Account Balance, Guaranteed Minimum Crediting Rate, Range from 0400 and Greater                                                                                                          |          |          |          |          |          |
| **Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]**                                                                                                                                       |          |          |          |          |          |
| Balance, end of period                                                                                                                                                                                                 | 282           |          |          | 288           |          |
| Universal life | Policyholder Account Balance, Guaranteed Minimum Crediting Rate, Range from 0400 and Greater | Policyholder Account Balance, at Guaranteed Minimum Crediting Rate                                     |          |          |          |          |          |
| **Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]**                                                                                                                                       |          |          |          |          |          |
| Balance, end of period                                                                                                                                                                                                 | 282           |          |          | 288           |          |
| Universal life | Policyholder Account Balance, Guaranteed Minimum Crediting Rate, Range from 0400 and Greater | Policyholder Account Balance, above Guaranteed Minimum Crediting Rate, Range from 0001 to 0050         |          |          |          |          |          |
| **Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]**                                                                                                                                       |          |          |          |          |          |
| Balance, end of period                                                                                                                                                                                                 | 0             |          |          | 0             |          |
| Universal life | Policyholder Account Balance, Guaranteed Minimum Crediting Rate, Range from 0400 and Greater | Policyholder Account Balance, above Guaranteed Minimum Crediting Rate, Range from 0051 to 0150         |          |          |          |          |          |
| **Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]**                                                                                                                                       |          |          |          |          |          |
| Balance, end of period                                                                                                                                                                                                 | 0             |          |          | 0             |          |
| Universal life | Policyholder Account Balance, Guaranteed Minimum Crediting Rate, Range from 0400 and Greater | Policyholder Account Balance, above Guaranteed Minimum Crediting Rate, Range from 0151 and Greater     |          |          |          |          |          |
| **Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]**                                                                                                                                       |          |          |          |          |          |
| Balance, end of period                                                                                                                                                                                                 | $ 0           |          |          | $ 0           |          |

| 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.
+ References
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|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount due to policyholder. Includes, but is not limited to, unpaid policy dividend, retrospective refund, and undistributed earnings on participating business. Excludes future policy benefit and claim expense.
+ References
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