Guaranteed Benefit Features (Summary Of Guaranteed Death Benefit Liabilities) (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Guaranteed Benefit Features [Abstract]
Balance as of beginning-of-year	$ 89	$ 73
Changes in reserves	17	12
Benefits paid	(11)	(10)
Balance as of end-of-period	$ 95	$ 75