Reserve for Unpaid Losses and Loss Adjustment Expenses - GB Liabilities for Unpaid Losses and Loss Adjustment Expenses (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021	Dec. 31, 2020
Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward]
Beginning liabilities for unpaid losses and loss adjustment expenses, gross	$ 39,659
Less: payments
Ending liabilities for unpaid losses and loss adjustment expenses, gross	40,601
Group Insurance Policy [Member]
Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward]
Beginning liabilities for unpaid losses and loss adjustment expenses, gross	8,210	$ 8,233
Reinsurance recoverables	251	246	$ 245	$ 237
Beginning liabilities for unpaid losses and loss adjustment expenses, net	7,965	7,996
Provision for unpaid losses and loss adjustment expense
Current incurral year	3,665	3,753
Prior year's discount accretion	156	155
Prior incurral year development [1]	(323)	(382)
Total provision for unpaid losses and loss adjustment expenses	3,498	3,526
Less: payments
Current incurral year	(1,703)	(1,776)
Prior incurral years	(1,900)	(1,804)
Total payments	(3,603)	(3,580)
Beginning liabilities for unpaid losses and loss adjustment expenses, net	7,860	7,942	$ 7,965	$ 7,996
Ending liabilities for unpaid losses and loss adjustment expenses, gross	8,111	8,188
Group Insurance Policy [Member] | Disability Insurance Policy [Member]
Provision for unpaid losses and loss adjustment expense
Prior incurral year development [1]	275	320
Group Insurance Policy [Member] | group life term, disability and accident [Member]
Provision for unpaid losses and loss adjustment expense
Prior incurral year development [1]	40	50
Group Insurance Policy [Member] | Other Operating Income (Expense) [Member]
Provision for unpaid losses and loss adjustment expense
Total provision for unpaid losses and loss adjustment expenses	$ 138	$ 131