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v3.24.2

Accelerating Aon United Program - Schedule of Changes in the Company’s Liabilities for the Program (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2024 | Jun. 30, 2023 | Jun. 30, 2024 | Jun. 30, 2023
Restructuring Reserve [Roll Forward] |  |  |  |
Charges | $ 132 | $ 0 | $ 251 | $ 0
Accelerating Aon United Program |  |  |  |
Restructuring Reserve [Roll Forward] |  |  |  |
Liability balance as of January 1, 2024 |  |  | 100 |
Charges | 132 |  | 251 |
Cash payments |  |  | (98) |
Foreign currency translation and other |  |  | (3) |
Non-cash charges |  |  | (92) |
Liability balance as of June 30, 2024 | 158 |  | 158 |
Total costs incurred from inception to date | 386 |  | 386 |
Asset amortization | 12 |  | 20 |
Accelerating Aon United Program | Technology and other |  |  |  |
Restructuring Reserve [Roll Forward] |  |  |  |
Liability balance as of January 1, 2024 |  |  | 14 |
Charges |  |  | 51 |
Cash payments |  |  | (29) |
Foreign currency translation and other |  |  | 0 |
Non-cash charges |  |  | (27) |
Liability balance as of June 30, 2024 | 9 |  | 9 |
Total costs incurred from inception to date | 65 |  | 65 |
Accelerating Aon United Program | Workforce optimization |  |  |  |
Restructuring Reserve [Roll Forward] |  |  |  |
Liability balance as of January 1, 2024 |  |  | 86 |
Charges |  |  | 145 |
Cash payments |  |  | (69) |
Foreign currency translation and other |  |  | (3) |
Non-cash charges |  |  | (10) |
Liability balance as of June 30, 2024 | 149 |  | 149 |
Total costs incurred from inception to date | 248 |  | 248 |
Accelerating Aon United Program | Asset impairments |  |  |  |
Restructuring Reserve [Roll Forward] |  |  |  |
Liability balance as of January 1, 2024 |  |  | 0 |
Charges |  |  | 55 |
Cash payments |  |  | 0 |
Foreign currency translation and other |  |  | 0 |
Non-cash charges |  |  | (55) |
Liability balance as of June 30, 2024 | 0 |  | 0 |
Total costs incurred from inception to date | $ 73 |  | $ 73 |

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