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Investments (Net Investment Income) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Investment income									$ 5,676	$ 6,144	$ 5,597
Investment expense									(402)	(305)	(333)
Net investment income	$ 1,343	$ 1,241	$ 1,338	$ 1,352	$ 1,374	$ 1,510	$ 1,509	$ 1,446	5,274	5,839	5,264
AFS Securities [Member]
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Investment income									4,408	4,242	4,241
Trading Securities [Member]
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Investment income									179	165	198
Equity Securities [Member]
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Investment income									11	3	3
Mortgage Loans On Real Estate [Member]
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Investment income									687	677	674
Policy loans [Member]
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Investment income									100	115	125
Cash And Cash [Member]
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Investment income									12		13
Commercial Mortgage Loan Prepayment And Bond Make Whole Premiums [Member]
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Investment income									100	195	78
Alternative investments [Member]
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Investment income									96	677	218
Consent fees [Member]
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Investment income									8	10	5
Other Investments [Member]
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Investment income									$ 75	$ 60	$ 42