Investments - Net Investment Income (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	$ 252	$ 258
Investment expenses	(9)	(8)
Net investment income (excluding net realized capital gains or losses)	243	250
Net realized capital gains (losses)	(75)	47
Net investment income	168	297
Yield-related impairment loss	18	30
Credit-related impairment loss	38	0
Supporting experience-rated products
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Net investment income	9	9
Debt securities
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	164	157
Mortgage loans
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	11	15
Other investments
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	$ 77	$ 86

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