Segment Information (Reconciliation Of Reportable Segments Operating Revenues To Total Revenues Reported In The Consolidated Statements Of Income) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Segment Reporting [Abstract]
Reportable segments operating revenues	$ 29,178	$ 25,177	$ 58,626	$ 49,565
Net investment income	57	285	311	495
Net realized gains (losses) on financial instruments	18	11	(6)	89
Total revenues	$ 29,264	$ 25,466	$ 58,885	$ 50,132