Investments - Detail of equity method investments (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025	Dec. 31, 2025
Schedule of Investments [Line Items]
Investments accounted for using the equity method	$ 2,458		$ 2,458		$ 2,421
Equity in earnings of partnerships and similar investments	45	$ 27	101	$ 34
Real estate-related investments
Schedule of Investments [Line Items]
Investments accounted for using the equity method	1,391		1,391		1,431
Equity in earnings of partnerships and similar investments	(16)	12	(9)	13
Private equity
Schedule of Investments [Line Items]
Investments accounted for using the equity method	964		964		895
Equity in earnings of partnerships and similar investments	60	13	106	14
Private debt
Schedule of Investments [Line Items]
Investments accounted for using the equity method	103		103		$ 95
Equity in earnings of partnerships and similar investments	$ 1	$ 2	$ 4	$ 7

This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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+ Details