Investments (Schedule Of Increase (Decrease) In Payables For Collateral On Investments) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Increase (decrease) in payables for collateral on investments
Collateral payable held for derivative investments	$ (286)	$ 1,035	$ (1,929)
Securities pledged under securities lending agreements	38	20	(13)
Securities pledged under reverse repurchase agreements	66	77	250
Securities pledged for TALF		(36)	(1)
Securities pledged for FHLBI	430	75	750
Total increase (decrease) in payables for collateral on investments	$ 248	$ 1,171	$ (943)