Investments In Unconsolidated Subsidiaries - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Schedule of Equity Method Investments [Line Items]
Revenue	$ 35,767	$ 31,949	$ 30,828
Investment management \| Real Estate Investments \| Related Party
Schedule of Equity Method Investments [Line Items]
Revenue	333	279	269
Related party receivable	156	83
Development and Construction Management Revenues \| Related Party
Schedule of Equity Method Investments [Line Items]
Revenue	114	165	$ 148
Related party receivable	$ 19	$ 30
Ownership Percentage \| Minimum
Schedule of Equity Method Investments [Line Items]
Equity method investments in unconsolidated subsidiaries, variations in ownership percentage	1.00%
Ownership Percentage \| Maximum
Schedule of Equity Method Investments [Line Items]
Equity method investments in unconsolidated subsidiaries, variations in ownership percentage	50.00%

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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