Investments (Equity Method Investments, Statement of Financial Position) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Investments [Abstract]
Total assets	$ 313,828	$ 78,546
Total liabilities	19,274	8,293
Partners’ capital	294,554	70,253
Total liabilities and partners’ capital	313,828	78,546
Total liabilities and partners’ capital included above	7,438	6,265
Equity in LP/LLC interests not included above	814	790
Carrying value	$ 8,252	$ 7,055