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Investments - Narrative (Details) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2021 USD ($) security | Mar. 31, 2020 USD ($) | Dec. 31, 2020 USD ($)
Schedule of Investments [Line Items] |  |  |
Unfunded commitments to limited partnerships | $ 260 |  | $ 290
Investments accounted for using the equity method | $ 1,324 |  | $ 1,235
Percentage (based on amount of unrealized loss) of available for sale fixed maturities that are in an unrealized loss position and rated investment grade | 75.00% |  |
Percentage (based on fair value) of available for sale fixed maturities that are in an unrealized loss position and rated investment grade | 91.00% |  |
Net investment income | $ 188 | $ 104 |
Realized gains (losses) on securities still owned | $ 77 | (328) |
Multifamily |  |  |
Schedule of Investments [Line Items] |  |  |
Percent of real-estate related investments by property type | 88.00% |  | 87.00%
Single Family |  |  |
Schedule of Investments [Line Items] |  |  |
Percent of real-estate related investments by property type | 2.00% |  | 2.00%
Other Property |  |  |
Schedule of Investments [Line Items] |  |  |
Percent of real-estate related investments by property type | 10.00% |  | 11.00%
Annuity subsidiaries |  |  |
Schedule of Investments [Line Items] |  |  |
Net investment income | $ 447 | 415 |
Annuity subsidiaries | Assets of discontinued annuity operations |  |  |
Schedule of Investments [Line Items] |  |  |
Investments accounted for using the equity method | 671 |  | $ 646
Neon Capital Limited |  |  |
Schedule of Investments [Line Items] |  |  |
Net investment income |  | (6) |
Fixed maturities |  |  |
Schedule of Investments [Line Items] |  |  |
Gross unrealized losses on fixed maturities | $ 16 |  | 21
Number of available for sale securities in an unrealized loss position | security | 434 |  |
Realized gains (losses) on securities still owned | $ 0 | (11) |
Available-for-sale Securities, Gross Realized Gains | 2 | 3 |
Available-for-sale Securities, Gross Realized Losses | (1) | (1) |
Fixed maturities | Annuity subsidiaries |  |  |
Schedule of Investments [Line Items] |  |  |
Available-for-sale Securities, Gross Realized Gains | 18 | 26 |
Available-for-sale Securities, Gross Realized Losses | (2) | (3) |
Fixed maturities | Annuity subsidiaries | Assets of discontinued annuity operations |  |  |
Schedule of Investments [Line Items] |  |  |
Gross unrealized losses on fixed maturities | $ 104 |  | $ 97
Accounting Standards Update 2016-01 | Equity securities | Neon Capital Limited |  |  |
Schedule of Investments [Line Items] |  |  |
Net investment income |  | $ (7) |

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