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	$ 160,534	$ 162,462
Balanced
Schedule of Fair Value of Separate Accounts by Major Category of Investment [Line Items]
Fund Groupings	77,991	79,473
Equity
Schedule of Fair Value of Separate Accounts by Major Category of Investment [Line Items]
Fund Groupings	68,400	69,973
Bond
Schedule of Fair Value of Separate Accounts by Major Category of Investment [Line Items]
Fund Groupings	12,854	11,783
Money Market
Schedule of Fair Value of Separate Accounts by Major Category of Investment [Line Items]
Fund Groupings	$ 1,289	$ 1,233