Investments (Net Investment Income) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Investment income	$ 6,144	$ 5,597	$ 5,366
Investment expense	(300)	(333)	(404)
Net investment income	5,844	5,264	4,962
Fixed Maturity AFS Securities [Member] | AFS Securities [Member]
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Investment income	4,242	4,241	4,214
Trading Securities [Member]
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Investment income	165	198	187
Equity Securities [Member]
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Investment income	3	3	4
Mortgage Loans On Real Estate [Member]
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Investment income	677	674	626
Real estate [Member]
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Investment income		1	1
Policy loans [Member]
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Investment income	115	124	128
Cash And Cash [Member]
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Investment income		13	33
Commercial Mortgage Loan Prepayment And Bond Make Whole Premiums [Member]
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Investment income	195	78	115
Alternative investments [Member]
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Investment income	677	218	24
Consent fees [Member]
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Investment income	10	5	7
Other Investments [Member]
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Investment income	$ 60	$ 42	$ 27