Investments (Fixed Maturity Securities - Narrative) (Details) $ in Millions	6 Months Ended
	Jun. 30, 2024 USD ($)	Jun. 30, 2023 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities, estimated fair value	$ 80,581		$ 80,991
Fixed maturity securities, allowance for credit losses	$ 45	$ 12	21	$ 7
Fixed maturity securities with allowance for credit losses, number of securities	27
Fixed maturity securities, total write-offs	$ 1	$ 7
Non-Income Producing
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities, estimated fair value	45		52
Fixed maturity securities
Debt Securities, Available-for-sale [Line Items]
Accrued interest receivable	$ 673		$ 655