Schedule IV Reinsurance Level 4 (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Life Insurance in Force, Net [Abstract]
Life Insurance in Force, Gross	$ 941,583	$ 914,556	$ 875,229
Ceded Premiums, Life Insurance in Force	220,747	227,553	240,285
Assumed Premiums, Life Insurance in Force	22,797	22,119	21,987
Premiums, Net, Life Insurance in Force	$ 743,633	$ 709,122	$ 656,931
Life Insurance in Force Premiums, Percentage Assumed to Net	3.00%	3.00%	3.00%
Insurance Services Revenue [Abstract]
Direct Premiums Earned	$ 16,553	$ 16,471	$ 16,560
Ceded Premiums Earned	2,234	2,293	2,419
Assumed From Other Companies	497	507	457
Premiums Earned, Net, Life	$ 14,816	$ 14,685	$ 14,598
Percentage of Amount Assumed to Net	3.00%	3.00%	3.00%
Property, Liability and Casualty Insurance Product Line [Member]
Insurance Services Revenue [Abstract]
Direct Premiums Earned	$ 10,871	$ 10,704	$ 10,531
Ceded Premiums Earned	583	586	699
Assumed From Other Companies	261	298	264
Premiums Earned, Net, Property and Casualty	$ 10,549	$ 10,416	$ 10,096
Percentage of Amount Assumed to Net	2.00%	3.00%	3.00%
Life and Annuity Insurance Product Line [Member]
Insurance Services Revenue [Abstract]
Gross Fee Income Earned Premium and Other Life	$ 3,993	$ 4,099	$ 4,414
Ceded Premiums Earned	1,618	1,650	1,666
Assumed From Other Companies	181	161	137
Premiums Earned, Net, Life	$ 2,556	$ 2,610	$ 2,885
Percentage of Amount Assumed to Net	7.00%	6.00%	5.00%
Accident and Health Insurance Product Line [Member]
Insurance Services Revenue [Abstract]
Gross Fee Income Earned Premium and Other Life	$ 1,689	$ 1,668	$ 1,615
Ceded Premiums Earned	33	57	54
Assumed From Other Companies	55	48	56
Premiums Earned, Net, Life	$ 1,711	$ 1,659	$ 1,617
Percentage of Amount Assumed to Net	3.00%	3.00%	3.00%

Gross fee income earned premium and other life.

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Amount of earned premiums assumed from other entities.

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