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Investments - Narrative (Details) $ in Millions | Mar. 31, 2023 USD ($) security | Dec. 31, 2022 USD ($)
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Schedule of Investments [Line Items] |  |
Unfunded commitments to limited partnerships | $ 412 | $ 396
Percentage (based on amount of unrealized loss) of available for sale fixed maturities that are in an unrealized loss position and rated investment grade | 94.00% |
Percentage (based on fair value) of available for sale fixed maturities that are in an unrealized loss position and rated investment grade | 95.00% |
Multifamily |  |
Schedule of Investments [Line Items] |  |
Percent of real-estate related investments by property type | 92.00% | 92.00%
Fixed maturities |  |
Schedule of Investments [Line Items] |  |
Gross unrealized losses on fixed maturities | $ 577 | $ 669
Number of available for sale securities in an unrealized loss position | security | 1,700,000,000 |

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