Investments (Fixed Maturity Securities - Narrative) (Details) $ in Millions	3 Months Ended
	Mar. 31, 2024 USD ($)	Mar. 31, 2023 USD ($)	Dec. 31, 2023 USD ($)
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities, estimated fair value	$ 79,602		$ 80,085
Fixed maturity securities, allowance for credit losses	$ 25		21
Fixed maturity securities with allowance for credit losses, number of securities	20
Fixed maturity securities, total write-offs	$ 0	$ 7
Non-Income Producing
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities, estimated fair value	51		52
Fixed maturity securities
Debt Securities, Available-for-sale [Line Items]
Accrued interest receivable	$ 701		$ 648