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Goodwill And Other Acquired Intangible Assets - Activity in Goodwill (Detail) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2024 | Dec. 31, 2023
Goodwill [Roll Forward] |  |
Beginning balance, goodwill gross |  | $ 5,851
Beginning balance, Accumulated impairment charge |  | (12)
Beginning balance, goodwill net |  | 5,839
Additions/ adjustments | $ 137 | 3
Foreign currency translation adjustments | 55 | 114
Ending balance, goodwill gross | 6,160 | 5,968
Ending balance, Accumulated impairment charge | (12) | (12)
Ending balance, goodwill net | 6,148 | 5,956
MA |  |
Goodwill [Roll Forward] |  |
Beginning balance, goodwill gross |  | 5,474
Beginning balance, Accumulated impairment charge |  | (12)
Beginning balance, goodwill net |  | 5,462
Additions/ adjustments | 39 | 90
Foreign currency translation adjustments | 54 | 117
Ending balance, goodwill gross | 5,774 | 5,681
Ending balance, Accumulated impairment charge | (12) | (12)
Ending balance, goodwill net | 5,762 | 5,669
MIS |  |
Goodwill [Roll Forward] |  |
Beginning balance, goodwill gross |  | 377
Beginning balance, Accumulated impairment charge |  | 0
Beginning balance, goodwill net |  | 377
Additions/ adjustments | 98 | (87)
Foreign currency translation adjustments | 1 | (3)
Ending balance, goodwill gross | 386 | 287
Ending balance, Accumulated impairment charge | 0 | 0
Ending balance, goodwill net | $ 386 | $ 287

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- Definition Goodwill additions and adjustments during the period, including the reallocation of goodwill pursuant to a realignment of certain components of the Company's ESG business in 2023. + References No definition available. + Details
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