Insurance (Fund Groupings) (Details) - Variable Annuity and Variable Life - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Fair Value, Separate Account Investment [Line Items]
Fund Groupings	$ 52,682	$ 49,793
Equity
Fair Value, Separate Account Investment [Line Items]
Fund Groupings	28,581	25,097
Balanced
Fair Value, Separate Account Investment [Line Items]
Fund Groupings	18,385	19,014
Bond
Fair Value, Separate Account Investment [Line Items]
Fund Groupings	5,567	5,565
Money Market
Fair Value, Separate Account Investment [Line Items]
Fund Groupings	$ 149	$ 117