v3.23.1
Investments - Value of other securities measured at fair value based on election of the fair value option (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2022
Dec. 31, 2021
Debt and Equity Securities, FV-NI [Line Items]    
Total fixed maturity securities [1] $ 3,769 $ 2,082
Equity securities [1] 170 242
Total $ 3,939 $ 2,324
Investment Concentration Risk | Investments    
Debt and Equity Securities, FV-NI [Line Items]    
Concentration risk, percentage 100.00% 100.00%
Fixed maturity securities    
Debt and Equity Securities, FV-NI [Line Items]    
Total fixed maturity securities $ 3,769 $ 2,082
Fixed maturity securities | Investment Concentration Risk | Investments    
Debt and Equity Securities, FV-NI [Line Items]    
Concentration risk, percentage 96.00% 90.00%
Fixed maturity securities | Obligations of states, municipalities and political subdivisions    
Debt and Equity Securities, FV-NI [Line Items]    
Total fixed maturity securities $ 37 $ 50
Fixed maturity securities | Obligations of states, municipalities and political subdivisions | Investment Concentration Risk | Investments    
Debt and Equity Securities, FV-NI [Line Items]    
Concentration risk, percentage 1.00% 2.00%
Fixed maturity securities | Non-U.S. governments    
Debt and Equity Securities, FV-NI [Line Items]    
Total fixed maturity securities $ 22 $ 17
Fixed maturity securities | Non-U.S. governments | Investment Concentration Risk | Investments    
Debt and Equity Securities, FV-NI [Line Items]    
Concentration risk, percentage 1.00% 1.00%
Fixed maturity securities | Corporate debt    
Debt and Equity Securities, FV-NI [Line Items]    
Total fixed maturity securities $ 2,222 $ 1,000
Fixed maturity securities | Corporate debt | Investment Concentration Risk | Investments    
Debt and Equity Securities, FV-NI [Line Items]    
Concentration risk, percentage 56.00% 43.00%
Fixed maturity securities | Mortgage-backed, asset-backed and collateralized    
Debt and Equity Securities, FV-NI [Line Items]    
Total fixed maturity securities $ 1,488 $ 1,015
Fixed maturity securities | Mortgage-backed, asset-backed and collateralized | Investment Concentration Risk | Investments    
Debt and Equity Securities, FV-NI [Line Items]    
Concentration risk, percentage 38.00% 44.00%
Fixed maturity securities | RMBS    
Debt and Equity Securities, FV-NI [Line Items]    
Total fixed maturity securities $ 165 $ 199
Fixed maturity securities | RMBS | Investment Concentration Risk | Investments    
Debt and Equity Securities, FV-NI [Line Items]    
Concentration risk, percentage 4.00% 9.00%
Fixed maturity securities | CMBS    
Debt and Equity Securities, FV-NI [Line Items]    
Total fixed maturity securities $ 232 $ 234
Fixed maturity securities | CMBS | Investment Concentration Risk | Investments    
Debt and Equity Securities, FV-NI [Line Items]    
Concentration risk, percentage 6.00% 10.00%
Fixed maturity securities | CLO    
Debt and Equity Securities, FV-NI [Line Items]    
Total fixed maturity securities $ 279 $ 283
Fixed maturity securities | CLO | Investment Concentration Risk | Investments    
Debt and Equity Securities, FV-NI [Line Items]    
Concentration risk, percentage 7.00% 12.00%
Fixed maturity securities | ABS    
Debt and Equity Securities, FV-NI [Line Items]    
Total fixed maturity securities $ 812 $ 299
Fixed maturity securities | ABS | Investment Concentration Risk | Investments    
Debt and Equity Securities, FV-NI [Line Items]    
Concentration risk, percentage 21.00% 13.00%
Equity securities    
Debt and Equity Securities, FV-NI [Line Items]    
Equity securities $ 170 $ 242
Equity securities | Investment Concentration Risk | Investments    
Debt and Equity Securities, FV-NI [Line Items]    
Concentration risk, percentage 4.00% 10.00%
[1] See Note 9 for details of balances associated with variable interest entities