Investments (Fair Value And Gross Unrealized Losses In A Continuous Unrealized Loss Position) (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2013 security	Dec. 31, 2012 security
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value
Less Than or Equal to Twelve Months	$ 17,233	$ 3,343
Greater Than Twelve Months	1,234	1,616
Continuous Unrealized Loss Position, Total	18,467	4,959
Available-for-sale Securities, Continuous Unrealized Loss Position, Gross Unrealized Losses and OTTI
Less Than or Equal to Twelve Months	1,067	214
Greater Than Twelve Months	247	301
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Losses	1,314	515
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions	1,361	626
Fixed Maturity Securities [Member]
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value
Less Than or Equal to Twelve Months	17,233	3,336
Greater Than Twelve Months	1,234	1,616
Continuous Unrealized Loss Position, Total	18,467	4,952
Available-for-sale Securities, Continuous Unrealized Loss Position, Gross Unrealized Losses and OTTI
Less Than or Equal to Twelve Months	1,067	212
Greater Than Twelve Months	247	301
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Losses	1,314	513
Equity AFS Securities [Member]
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value
Less Than or Equal to Twelve Months		7
Continuous Unrealized Loss Position, Total		7
Available-for-sale Securities, Continuous Unrealized Loss Position, Gross Unrealized Losses and OTTI
Less Than or Equal to Twelve Months		2
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Losses		2
Corporate Bonds [Member] | Fixed Maturity Securities [Member]
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value
Less Than or Equal to Twelve Months	15,900	2,853
Greater Than Twelve Months	820	934
Continuous Unrealized Loss Position, Total	16,720	3,787
Available-for-sale Securities, Continuous Unrealized Loss Position, Gross Unrealized Losses and OTTI
Less Than or Equal to Twelve Months	978	145
Greater Than Twelve Months	169	182
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Losses	1,147	327
Fixed maturity U.S. Government Bonds [Member] | Fixed Maturity Securities [Member]
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value
Less Than or Equal to Twelve Months	145
Continuous Unrealized Loss Position, Total	145
Available-for-sale Securities, Continuous Unrealized Loss Position, Gross Unrealized Losses and OTTI
Less Than or Equal to Twelve Months	9
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Losses	9
RMBS [Member] | Fixed Maturity Securities [Member]
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value
Less Than or Equal to Twelve Months	635	272
Greater Than Twelve Months	100	199
Continuous Unrealized Loss Position, Total	735	471
Available-for-sale Securities, Continuous Unrealized Loss Position, Gross Unrealized Losses and OTTI
Less Than or Equal to Twelve Months	30	39
Greater Than Twelve Months	10	24
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Losses	40	63
CMBS [Member] | Fixed Maturity Securities [Member]
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value
Less Than or Equal to Twelve Months	117	66
Greater Than Twelve Months	29	113
Continuous Unrealized Loss Position, Total	146	179
Available-for-sale Securities, Continuous Unrealized Loss Position, Gross Unrealized Losses and OTTI
Less Than or Equal to Twelve Months	19	16
Greater Than Twelve Months	2	19
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Losses	21	35
CDOs [Member] | Fixed Maturity Securities [Member]
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value
Less Than or Equal to Twelve Months	73	10
Greater Than Twelve Months	45	53
Continuous Unrealized Loss Position, Total	118	63
Available-for-sale Securities, Continuous Unrealized Loss Position, Gross Unrealized Losses and OTTI
Less Than or Equal to Twelve Months	7	8
Greater Than Twelve Months	1	3
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Losses	8	11
State And Municipal Bonds [Member] | Fixed Maturity Securities [Member]
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value
Less Than or Equal to Twelve Months	303	64
Greater Than Twelve Months	22	24
Continuous Unrealized Loss Position, Total	325	88
Available-for-sale Securities, Continuous Unrealized Loss Position, Gross Unrealized Losses and OTTI
Less Than or Equal to Twelve Months	18	1
Greater Than Twelve Months	6	6
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Losses	24	7
Hybrid And Redeemable Preferred Securities [Member] | Fixed Maturity Securities [Member]
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value
Less Than or Equal to Twelve Months	60	71
Greater Than Twelve Months	218	293
Continuous Unrealized Loss Position, Total	278	364
Available-for-sale Securities, Continuous Unrealized Loss Position, Gross Unrealized Losses and OTTI
Less Than or Equal to Twelve Months	6	3
Greater Than Twelve Months	59	67
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Losses	$ 65	$ 70