Investments - Detail of equity method investments (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Schedule of Investments [Line Items]
Investments accounted for using the equity method	$ 1,324		$ 1,235
Equity in earnings of partnerships and similar investments	78	$ 23
Real estate-related investments
Schedule of Investments [Line Items]
Investments accounted for using the equity method	985		915
Equity in earnings of partnerships and similar investments	54	26
Private equity
Schedule of Investments [Line Items]
Investments accounted for using the equity method	284		266
Equity in earnings of partnerships and similar investments	21	(5)
Private debt
Schedule of Investments [Line Items]
Investments accounted for using the equity method	55		$ 54
Equity in earnings of partnerships and similar investments	$ 3	$ 2

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

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