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Accounting Policies - Narrative (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024 | Dec. 31, 2024
Variable Interest Entity [Line Items] |  |  |  |  |
Assets of managed investment entities | $ 3,972 |  | $ 3,972 |  | $ 4,140
Liabilities of managed investment entities | 3,834 |  | 3,834 |  | 3,965
Operating lease liability | $ 224 |  | $ 224 |  | $ 232
Operating lease liability, current, Statement of Financial Position | Other Liabilities |  | Other Liabilities |  | Other Liabilities
Operating lease right-of-use asset | $ 201 |  | $ 201 |  | $ 212
Operating lease, right-of-use asset, Statement of Financial Position | Other Assets |  | Other Assets |  | Other Assets
Weighted average common shares adjustment related to stock-based compensation (shares) | 0 | 0 |  | 100,000 |
Anti-dilutive potential common shares related to stock-based compensation plans (shares) | 0 | 0 | 0 | 0 |
Maturities of short term investments |  |  | 3 months |  |
New collateralized loan obligation, temporary warehousing entities |  |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |  |
Assets of managed investment entities | $ 49 |  | $ 49 |  |
Liabilities of managed investment entities | $ 41 |  | $ 41 |  |
Maximum |  |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |  |
Weighted average common shares adjustment related to stock-based compensation (shares) |  |  | 100,000 |  |

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