Reinsurance Level 4 Insurance Revenue (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Policyholder Benefits and Claims Incurred, Ceded		$ 336	$ 0	$ 459
Insurance Recoveries		1,111	863	913
Premiums Earned, Net [Abstract]
Direct Premiums Earned		16,471	16,560	16,929
Assumed Premiums Earned		507	457	379
Ceded Premiums Earned		2,293	2,419	2,651
Premiums Earned, Net, Life		14,685	14,598	14,657
Life Insurance Product Line [Member]
Premiums Earned, Net [Abstract]
Gross Fee Income Earned Premium and Other Life	$ 6,435	5,767	6,029
Assumed Premiums Earned	138	209	193
Ceded Premiums Earned	$ 1,780	1,707	1,720
Premiums Earned, Net, Life		4,269	4,502	4,793
Property, Liability and Casualty Insurance Product Line [Member]
Premiums Written, Net [Abstract]
Direct Premiums Written		10,861	10,571	10,564
Assumed Premiums Written		297	275	247
Ceded Premiums Written		(580)	(602)	(882)
Premiums Written, Net		10,578	10,244	9,929
Premiums Earned, Net [Abstract]
Direct Premiums Earned		10,704	10,531	10,494
Assumed Premiums Earned		298	264	241
Ceded Premiums Earned		586	699	871
Premiums Earned, Net, Property and Casualty		$ 10,416	$ 10,096	$ 9,864