Policy Claims and Benefits Policy Claims and Benefits (Rollforward of Claims and Claim Adjustment Expense) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward]
Liability for Claims and Claims Adjustment Expense Beginning Balance	$ 8,053	$ 7,556	$ 6,786
Reinsurance Recoverable for Unpaid Claims and Claims Adjustments, Beginning Balance	(556)	(641)	(564)
Liability For Unpaid Claims And Claims Adjustment Expense Net Of Recoverable, Beginning Balance	7,497	6,915	6,222
Current Year Claims and Claims Adjustment Expense	11,018	13,181	11,195
Prior Year Claims and Claims Adjustment Expense	(143)	(377)	(123)
Liability for Unpaid Claims and Claims Adjustment Expense, Incurred Claims	10,875	12,804	11,318
Liability for Unpaid Claims and Claims Adjustment Expense, Claims Paid, Current Year	(4,282)	(6,284)	(5,617)
Liability for Unpaid Claims and Claims Adjustment Expense, Claims Paid, Prior Years	(6,634)	(5,810)	(5,204)
Liability for Unpaid Claims and Claims Adjustment Expense, Claims Paid	(10,916)	(12,094)	(10,821)
Interest On Liability For Policy And Contract Claims	34	31	36
Liability for Unpaid Claims and Claims Adjustment Expense, Foreign Currency Translation Gain (Loss)	(285)	159	(160)
Liability for Unpaid Claims and Claims Adjustment Expense Other	(251)	(128)	(196)
Liability For Unpaid Claims And Claims Adjustment Expense Net Of Recoverable, Ending Balance	7,205	7,497	6,915
Reinsurance Recoverable for Unpaid Claims and Claims Adjustments, Ending Balance	439	556	641
Liability for Claims and Claims Adjustment Expense, Ending Balance	$ 7,644	$ 8,053	$ 7,556