Segment Information (Premiums, Universal Life and Investment-Type Policy Fees and Other Revenues by Major Product Groups) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Segment Reporting Information [Line Items]
Total premiums, universal life and investment-type product policy fees and other revenues	$ 50,118	$ 50,035	$ 51,043
Life insurance (1)
Segment Reporting Information [Line Items]
Total premiums, universal life and investment-type product policy fees and other revenues	22,755	23,037	23,483
Accident & health insurance
Segment Reporting Information [Line Items]
Total premiums, universal life and investment-type product policy fees and other revenues	14,150	13,090	13,336
Annuities
Segment Reporting Information [Line Items]
Total premiums, universal life and investment-type product policy fees and other revenues	8,982	9,653	9,984
Property & casualty insurance
Segment Reporting Information [Line Items]
Total premiums, universal life and investment-type product policy fees and other revenues	3,560	3,504	3,524
Non-insurance
Segment Reporting Information [Line Items]
Total premiums, universal life and investment-type product policy fees and other revenues	$ 671	$ 751	$ 716