Guaranteed Benefit Features (Summary Of Guaranteed Death Benefit Liabilities) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Guaranteed Benefit Features [Abstract]
Balance as of beginning-of-year	$ 121	$ 117	$ 161
Changes in reserves	31	30	(24)
Benefits paid	(20)	(26)	(20)
Balance as of end-of-period	$ 132	$ 121	$ 117