Investments (Schedule Of Changes in Amount Of Credit Losses Of OTTI Recognized In Net Income (Loss)) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Investments [Abstract]
Balance as of beginning of period	$ 413	$ 415	$ 424	$ 390
Increases attributable to:
Credit losses on securities for which an OTTI was not previously recognized	6	19	26	74
Credit losses on securities for which an OTTI was previously recognized	16	18	37	60
Decreases attributable to:
Securities sold	(16)	(19)	(68)	(91)
Balance as of end of period	$ 419	$ 433	$ 419	$ 433