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Investments - Detail of equity method investments (Details) - USD ($) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2026 | Mar. 31, 2025 | Dec. 31, 2025
Schedule of Investments [Line Items] |  |  |
Investments accounted for using the equity method | $ 2,443 |  | $ 2,421
Equity in earnings of partnerships and similar investments | $ 18 | $ 13 |
Multifamily |  |  |
Schedule of Investments [Line Items] |  |  |
Percent of real-estate related investments by property type | 88.00% |  | 87.00%
Real estate-related investments |  |  |
Schedule of Investments [Line Items] |  |  |
Investments accounted for using the equity method | $ 1,418 |  | $ 1,431
Equity in earnings of partnerships and similar investments | 5 | 17 |
Private equity |  |  |
Schedule of Investments [Line Items] |  |  |
Investments accounted for using the equity method | 927 |  | 895
Equity in earnings of partnerships and similar investments | 10 | (6) |
Private debt |  |  |
Schedule of Investments [Line Items] |  |  |
Investments accounted for using the equity method | 98 |  | $ 95
Equity in earnings of partnerships and similar investments | $ 3 | $ 2 |

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