Insurance (Fund Groupings) (Details) - Variable Annuity and Variable Life - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Fair Value, Separate Account Investment [Line Items]
Fund Groupings	$ 95,591	$ 88,159
Balanced
Fair Value, Separate Account Investment [Line Items]
Fund Groupings	62,266	58,258
Equity
Fair Value, Separate Account Investment [Line Items]
Fund Groupings	25,580	22,292
Bond
Fair Value, Separate Account Investment [Line Items]
Fund Groupings	7,729	7,592
Money Market
Fair Value, Separate Account Investment [Line Items]
Fund Groupings	$ 16	$ 17