Investments - Net Investment Income (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2020
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	$ 1,591	$ 1,691	$ 2,019
Less: Investment expenses	68	72	70
Net investment income	1,523	1,619	1,949
Fixed maturities
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	1,285	1,411	1,453
Financing Receivable, Nonaccrual	7	8
Equity securities
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	10	10	12
Mortgage loans on real estate
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	196	181	179
Policy loans
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	8	8	8
Short-term investments and cash equivalents
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	10	4	3
Limited partnerships and other
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	$ 82	$ 77	$ 364