Guaranteed Benefit Features (Information On Guaranteed Death Benefit Features) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014		Dec. 31, 2013
Return of Net Deposits [Member]
Net Amount at Risk by Product and Guarantee [Line Items]
Total Account Value	$ 85,917	[1]	$ 79,391	[1]
Net amount at risk	183	[1],[2]	141	[1],[2]
Average attained age of contract holders	62 years	[1]	61 years	[1]
Minimum Return [Member]
Net Amount at Risk by Product and Guarantee [Line Items]
Total Account Value	135	[1]	151	[1]
Net amount at risk	25	[1],[2]	27	[1],[2]
Average attained age of contract holders	74 years	[1]	73 years	[1]
Guaranteed minimum return	5.00%	[1]	5.00%	[1]
Anniversary Contract Value [Member]
Net Amount at Risk by Product and Guarantee [Line Items]
Total Account Value	26,021	[1]	25,958	[1]
Net amount at risk	$ 597	[1],[2]	$ 570	[1],[2]
Average attained age of contract holders	68 years	[1]	68 years	[1]

[1] Our variable contracts with guarantees may offer more than one type of guarantee in each contract; therefore, the amounts listed are not mutually exclusive.

[2] Represents the amount of death benefit in excess of the account balance that is subject to market volatility.