Investments (Select Information For Securities In A Gross Unrealized Loss Position) (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended	12 Months Ended
	Sep. 30, 2014	Dec. 31, 2013
Schedule Of Available For Sale Securities Residential And Commercial Mortgage At Risk [Line Items]
Amortized cost	$ 79,287	$ 77,217
Fair Value	86,180	80,976
AFS Securities Backed By Pools Of Residential Mortgages [Member]
Schedule Of Available For Sale Securities Residential And Commercial Mortgage At Risk [Line Items]
Amortized cost	1,088	1,261
Fair Value	1,024	1,146
Gross Unrealized Losses	64	115
AFS Securities Backed By Pools Of Commercial Mortgages [Member]
Schedule Of Available For Sale Securities Residential And Commercial Mortgage At Risk [Line Items]
Amortized cost	148	193
Fair Value	134	169
Gross Unrealized Losses	14	24
Total AFS Securities Backed By Pools Of Residential And Commercial Mortgages [Member]
Schedule Of Available For Sale Securities Residential And Commercial Mortgage At Risk [Line Items]
Amortized cost	1,236	1,454
Fair Value	1,158	1,315
Gross Unrealized Losses	78	139
AFS Securities Subject To Detailed Analysis Backed By Pools Of Residential Mortgages [Member]
Schedule Of Available For Sale Securities Residential And Commercial Mortgage At Risk [Line Items]
Amortized cost	790	933
Fair Value	731	833
Gross Unrealized Losses	59	100
AFS Securities Subject To Detailed Analysis Backed By Pools Of Commercial Mortgages [Member]
Schedule Of Available For Sale Securities Residential And Commercial Mortgage At Risk [Line Items]
Amortized cost	26	29
Fair Value	25	24
Gross Unrealized Losses	1	5
AFS Securities Subject To Detailed Analysis Backed By Pools Of Residential And Commercial Mortgages [Member]
Schedule Of Available For Sale Securities Residential And Commercial Mortgage At Risk [Line Items]
Amortized cost	816	962
Fair Value	756	857
Gross Unrealized Losses	$ 60	$ 105