| **Fair Value Measurements - Fair Value of Life Policy Loans, Deferred Annuities, and Structured Settlements (Details) - USD ($) $ in Millions** | Sep. 30, 2023 | Dec. 31, 2022 |
|-------------------------------------------------------------------------------------------------------------------------------------------------|---------------|---------------|
| **Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis**                                                             |          |          |
| Fair value of life policy loans                                                                                                                 | $ 36          | $ 37          |
| Liabilities Related to Investment Contracts, Fair Value Disclosure                                                                              | 724           | 764           |
| Level 1                                                                                                                                    |          |          |
| **Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis**                                                             |          |          |
| Fair value of life policy loans                                                                                                                 | 0             | 0             |
| Liabilities Related to Investment Contracts, Fair Value Disclosure                                                                              | 0             | 0             |
| Level 2                                                                                                                                    |          |          |
| **Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis**                                                             |          |          |
| Fair value of life policy loans                                                                                                                 | 0             | 0             |
| Liabilities Related to Investment Contracts, Fair Value Disclosure                                                                              | 129           | 143           |
| Level 3                                                                                                                                    |          |          |
| **Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis**                                                             |          |          |
| Fair value of life policy loans                                                                                                                 | 36            | 37            |
| Liabilities Related to Investment Contracts, Fair Value Disclosure                                                                              | 595           | 621           |
| Deferred annuities                                                                                                                              |          |          |
| **Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis**                                                             |          |          |
| Liabilities Related to Investment Contracts, Fair Value Disclosure                                                                              | 595           | 621           |
| Deferred annuities | Level 1                                                                                                               |          |          |
| **Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis**                                                             |          |          |
| Liabilities Related to Investment Contracts, Fair Value Disclosure                                                                              | 0             | 0             |
| Deferred annuities | Level 2                                                                                                               |          |          |
| **Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis**                                                             |          |          |
| Liabilities Related to Investment Contracts, Fair Value Disclosure                                                                              | 0             | 0             |
| Deferred annuities | Level 3                                                                                                               |          |          |
| **Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis**                                                             |          |          |
| Liabilities Related to Investment Contracts, Fair Value Disclosure                                                                              | 595           | 621           |
| Structured settlements                                                                                                                          |          |          |
| **Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis**                                                             |          |          |
| Liabilities Related to Investment Contracts, Fair Value Disclosure                                                                              | 129           | 143           |
| Structured settlements | Level 1                                                                                                           |          |          |
| **Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis**                                                             |          |          |
| Liabilities Related to Investment Contracts, Fair Value Disclosure                                                                              | 0             | 0             |
| Structured settlements | Level 2                                                                                                           |          |          |
| **Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis**                                                             |          |          |
| Liabilities Related to Investment Contracts, Fair Value Disclosure                                                                              | 129           | 143           |
| Structured settlements | Level 3                                                                                                           |          |          |
| **Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis**                                                             |          |          |
| Liabilities Related to Investment Contracts, Fair Value Disclosure                                                                              | $ 0           | $ 0           |

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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.
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Fair value portion of liability related to investment contracts for example, but not limited to, guaranteed investment contract or annuities.
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|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.
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