Liability For Unpaid Claims (Changes In Liability For Unpaid Claims) (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Liability For Unpaid Claims [Abstract]
Balance as of beginning-of-year	$ 5,552	$ 5,335
Reinsurance recoverable	152	143
Net balance as of beginning-of-year	5,400	5,192
Incurred related to:
Current year	2,615	2,370
Interest	116	117
All other incurred	(157)	(203)
Total incurred	2,574	2,284
Paid related to:
Current year	(1,184)	(1,046)
Prior years	(1,118)	(1,091)
Total paid	(2,302)	(2,137)
Net balance as of end-of-year	5,672	5,339
Reinsurance recoverable	149	148
Balance as of end-of-year	$ 5,821	$ 5,487