Investments - Net Investment Income (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	$ 253	$ 285	$ 505	$ 543
Investment expenses	(9)	(9)	(18)	(17)
Net investment income (excluding net realized capital gains or losses)	244	276	487	526
Net realized capital gains (losses)	(98)	13	(173)	60
Net investment income	146	289	314	586
Credit-related impairment loss	(22)	0	16	0
Yield-related impairment loss	30	2	48	32
Supporting experience-rated products
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Net investment income	9	10	18	19
Debt securities
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	172	160	336	317
Mortgage loans
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	13	13	24	28
Other investments
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	$ 68	$ 112	$ 145	$ 198

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