Reinsurance (Consolidated Reinsurance) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Premiums written [Abstract]
Direct	$ 47,511	$ 42,811	$ 37,749
Assumed	4,502	3,969	3,512
Ceded	(10,258)	(8,912)	(7,441)
Net	41,755	37,868	33,820
Premiums earned [Abstract]
Direct	46,154	41,138	37,037
Assumed	4,430	3,650	3,323
Ceded	(10,195)	(8,433)	(7,243)
Net premiums earned	40,389	36,355	33,117
Policyholder Benefits and Claims Incurred, Ceded	$ 7,000	$ 6,100	$ 5,000