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	$ 4,378	$ 4,877	$ 4,884
Annuity products
Segment Reporting Information [Line Items]
Total premiums, universal life and investment-type product policy fees and other revenues	3,300	3,568	3,926
Life insurance (1)
Segment Reporting Information [Line Items]
Total premiums, universal life and investment-type product policy fees and other revenues	1,055	1,176	953
Other products
Segment Reporting Information [Line Items]
Total premiums, universal life and investment-type product policy fees and other revenues	$ 23	$ 133	$ 5