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Goodwill and Other Intangible Assets - Schedule of Other Intangible Assets by Asset Class (Details) - USD ($) $ in Millions | Sep. 30, 2025 | Sep. 03, 2025 | Dec. 31, 2024
--- | --- | --- | ---
Finite-Lived Intangible Assets [Line Items] |  |  |
Gross Carrying Amount | $ 8,742 |  | $ 9,172
Accumulated Amortization and Impairment | 2,915 |  | 2,429
Total | 5,827 |  | 6,743
Held-for-sale | NFP Acquisition |  |  |
Finite-Lived Intangible Assets [Line Items] |  |  |
Gross intangibles held for sale |  | $ 754 |
Customer-related and contract-based |  |  |
Finite-Lived Intangible Assets [Line Items] |  |  |
Gross Carrying Amount | 7,660 |  | 7,994
Accumulated Amortization and Impairment | 2,488 |  | 2,050
Total | 5,172 |  | 5,944
Tradenames |  |  |
Finite-Lived Intangible Assets [Line Items] |  |  |
Gross Carrying Amount | 715 |  | 812
Accumulated Amortization and Impairment | 103 |  | 66
Total | 612 |  | 746
Technology and other |  |  |
Finite-Lived Intangible Assets [Line Items] |  |  |
Gross Carrying Amount | 367 |  | 366
Accumulated Amortization and Impairment | 324 |  | 313
Total | $ 43 |  | $ 53

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