Insurance (Fund Groupings) (Details) - Variable Annuity and Variable Life - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Schedule of Fair Value of Separate Accounts by Major Category of Investment [Line Items]
Fund Groupings	$ 95,353	$ 96,709
Balanced
Schedule of Fair Value of Separate Accounts by Major Category of Investment [Line Items]
Fund Groupings	49,224	49,870
Equity
Schedule of Fair Value of Separate Accounts by Major Category of Investment [Line Items]
Fund Groupings	39,749	41,269
Bond
Schedule of Fair Value of Separate Accounts by Major Category of Investment [Line Items]
Fund Groupings	5,726	4,802
Money Market
Schedule of Fair Value of Separate Accounts by Major Category of Investment [Line Items]
Fund Groupings	$ 654	$ 768