Other Assets - Equity Method Investments - Balances (Details) - Investment Management - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Equity Method Investments
Investments	$ 2,138		$ 2,214
Income (loss)	$ 6	$ (24)

Amount of income (loss) for proportionate share of equity method investee's income (loss).

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