Consolidated Reinsurance (Consolidated Reinsurance) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Direct Premiums, Life Insurance in Force	$ 4,752,050	$ 4,718,278	$ 4,572,115
Ceded Premiums, Life Insurance in Force	680,460	751,199	719,154
Assumed Premiums, Life Insurance in Force	613,693	602,213	649,032
Premiums, Net, Life Insurance in Force	$ 4,685,283	$ 4,569,292	$ 4,501,993
Life Insurance in Force Premiums, Percentage Assumed to Net	13.10%	13.20%	14.40%
Consolidated Reinsurance
Gross Amount	$ 40,271	$ 39,516	$ 40,049
Ceded	2,523	2,425	2,454
Assumed	1,405	1,454	1,472
Net premiums	$ 39,153	$ 38,545	$ 39,067
% Amount Assumed to Net	3.60%	3.80%	3.80%
Life insurance (1)
Consolidated Reinsurance
Gross Amount	$ 23,006	$ 23,308	$ 23,575
Ceded	2,001	1,964	2,034
Assumed	1,133	1,221	1,224
Net premiums	$ 22,138	$ 22,565	$ 22,765
% Amount Assumed to Net	5.10%	5.40%	5.40%
Accident & health insurance
Consolidated Reinsurance
Gross Amount	$ 13,698	$ 12,695	$ 13,015
Ceded	447	385	340
Assumed	255	220	239
Net premiums	$ 13,506	$ 12,530	$ 12,914
% Amount Assumed to Net	1.90%	1.80%	1.90%
Property & casualty insurance
Consolidated Reinsurance
Gross Amount	$ 3,567	$ 3,513	$ 3,459
Ceded	75	76	80
Assumed	17	13	9
Net premiums	$ 3,509	$ 3,450	$ 3,388
% Amount Assumed to Net	0.50%	0.40%	0.30%