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Accounting Policies - Narrative (Details) $ in Millions | 12 Months Ended
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Dec. 31, 2024 USD ($) Businesses shares | Dec. 31, 2023 USD ($) shares | Dec. 31, 2022 shares
Significant Accounting Policies [Line Items] |  |  |
Number of businesses acquired during period | Businesses | 2 |  |
Assets of managed investment entities | $ 4,140 | $ 4,484 |
Liabilities of managed investment entities | $ 3,965 | $ 4,307 |
Weighted average common shares adjustment related to stock-based compensation | shares |  | 100,000 | 200,000
Anti-dilutive potential common shares related to stock-based compensation plans | shares | 0 | 0 | 0
Maturities of short term investments | 3 months |  |
Maximum |  |  |
Significant Accounting Policies [Line Items] |  |  |
Weighted average common shares adjustment related to stock-based compensation | shares | 100,000 |  |
New collateralized loan obligation, temporary warehousing entities |  |  |
Significant Accounting Policies [Line Items] |  |  |
Assets of managed investment entities | $ 302 |  |
Liabilities of managed investment entities | $ 253 |  |

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