Investments (Schedule of Details Of The Amount Of Credit Losses Of OTTI Recognized In Net Income (Loss)) (Details) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
	Jun. 30, 2016	Dec. 31, 2015	Mar. 31, 2016	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items]
Amortized Cost	$ 689	$ 640
Net Unrealized Gain/(Loss) Position	(1)	30
Fair Value	688	670
OTTI in Credit Losses	431	382	$ 413	$ 374	$ 382	$ 380
Corporate bonds [Member]
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items]
Amortized Cost	91	31
Net Unrealized Gain/(Loss) Position	(15)	(2)
Fair Value	76	29
OTTI in Credit Losses	85	28
ABS [Member]
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items]
Amortized Cost	198	199
Net Unrealized Gain/(Loss) Position	8	13
Fair Value	206	212
OTTI in Credit Losses	109	108
RMBS [Member]
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items]
Amortized Cost	353	365
Net Unrealized Gain/(Loss) Position		12
Fair Value	353	377
OTTI in Credit Losses	194	193
CMBS [Member]
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items]
Amortized Cost	32	34
Net Unrealized Gain/(Loss) Position	3	4
Fair Value	35	38
OTTI in Credit Losses	37	48
CLOs [Member]
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items]
Amortized Cost	11	11
Net Unrealized Gain/(Loss) Position	4	3
Fair Value	15	14
OTTI in Credit Losses	5	$ 5
State and municipal bonds [Member]
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items]
Amortized Cost	4
Net Unrealized Gain/(Loss) Position	(1)
Fair Value	3
OTTI in Credit Losses	$ 1