Investments - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Investment [Line Items]
Fixed income securities	$ 42,136	$ 42,565
Short-term investments	$ 4,009	6,807
Percentage of credit concentration risk of single issuer and affiliates of shareholder's equity	10.00%
Fixed income and equity securities carrying value	$ 1,380	872
Interest income on collateral, net of fees	1	2	$ 3
Debt Securities below Investment Grade	7,500	6,060
Fixed income and short-term investments carrying value	211
Non-income producing fixed income securities	57
Accrued investment income	339	371
Municipal
Investment [Line Items]
Fixed income securities	6,393	7,578
Fixed income securities
Investment [Line Items]
Accrued investment income	$ 311	$ 351

Below investment grade assets included in fixed income securities.

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