Investments - Detail of equity method investments (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Schedule of Investments [Line Items]
Investments accounted for using the equity method	$ 1,517	$ 1,235
Equity in earnings of partnerships and similar investments	321	99	$ 97
Real estate-related investments
Schedule of Investments [Line Items]
Investments accounted for using the equity method	1,130	915
Equity in earnings of partnerships and similar investments	226	92	67
Private equity
Schedule of Investments [Line Items]
Investments accounted for using the equity method	352	266
Equity in earnings of partnerships and similar investments	100	18	24
Private debt
Schedule of Investments [Line Items]
Investments accounted for using the equity method	35	54
Equity in earnings of partnerships and similar investments	$ (5)	$ (11)	$ 6

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

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