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v3.24.3

Accelerating Aon United Program - Schedule of Changes in the Company’s Liabilities for the Program (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2024 | Sep. 30, 2023 | Sep. 30, 2024 | Sep. 30, 2023
Restructuring Reserve [Roll Forward] |  |  |  |
Charges | $ 69 | $ 6 | $ 320 | $ 6
Accelerating Aon United Program |  |  |  |
Restructuring Reserve [Roll Forward] |  |  |  |
Liability balance as of January 1, 2024 |  |  | 100 |
Charges | 69 |  | 320 |
Cash payments |  |  | (183) |
Foreign currency translation and other |  |  | 2 |
Non-cash charges |  |  | (94) |
Liability balance as of September 30, 2024 | 145 |  | 145 |
Total costs incurred from inception to date | 455 |  | 455 |
Asset amortization | 4 |  | 24 |
Accelerating Aon United Program | Technology and other |  |  |  |
Restructuring Reserve [Roll Forward] |  |  |  |
Liability balance as of January 1, 2024 |  |  | 14 |
Charges |  |  | 87 |
Cash payments |  |  | (63) |
Foreign currency translation and other |  |  | 0 |
Non-cash charges |  |  | (24) |
Liability balance as of September 30, 2024 | 14 |  | 14 |
Total costs incurred from inception to date | 101 |  | 101 |
Accelerating Aon United Program | Workforce optimization |  |  |  |
Restructuring Reserve [Roll Forward] |  |  |  |
Liability balance as of January 1, 2024 |  |  | 86 |
Charges |  |  | 173 |
Cash payments |  |  | (120) |
Foreign currency translation and other |  |  | 2 |
Non-cash charges |  |  | (10) |
Liability balance as of September 30, 2024 | 131 |  | 131 |
Total costs incurred from inception to date | 276 |  | 276 |
Accelerating Aon United Program | Asset impairments |  |  |  |
Restructuring Reserve [Roll Forward] |  |  |  |
Liability balance as of January 1, 2024 |  |  | 0 |
Charges |  |  | 60 |
Cash payments |  |  | 0 |
Foreign currency translation and other |  |  | 0 |
Non-cash charges |  |  | (60) |
Liability balance as of September 30, 2024 | 0 |  | 0 |
Total costs incurred from inception to date | $ 78 |  | $ 78 |

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