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Goodwill And Other Acquired Intangible Assets - Activity in Goodwill (Detail) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2024 | Dec. 31, 2023
Goodwill [Roll Forward] |  |
Beginning balance, goodwill gross | $ 5,968 | $ 5,851
Beginning balance, Accumulated impairment charge | (12) | (12)
Beginning balance, goodwill net | 5,956 | 5,839
Additions/ adjustments | 15 | 3
Foreign currency translation adjustments | (62) | 114
Ending balance, goodwill gross | 5,921 | 5,968
Ending balance, Accumulated impairment charge | (12) | (12)
Ending balance, goodwill net | 5,909 | 5,956
MA |  |
Goodwill [Roll Forward] |  |
Beginning balance, goodwill gross | 5,681 | 5,474
Beginning balance, Accumulated impairment charge | (12) | (12)
Beginning balance, goodwill net | 5,669 | 5,462
Additions/ adjustments | 13 | 90
Foreign currency translation adjustments | (61) | 117
Ending balance, goodwill gross | 5,633 | 5,681
Ending balance, Accumulated impairment charge | (12) | (12)
Ending balance, goodwill net | 5,621 | 5,669
MIS |  |
Goodwill [Roll Forward] |  |
Beginning balance, goodwill gross | 287 | 377
Beginning balance, Accumulated impairment charge | 0 | 0
Beginning balance, goodwill net | 287 | 377
Additions/ adjustments | 2 | (87)
Foreign currency translation adjustments | (1) | (3)
Ending balance, goodwill gross | 288 | 287
Ending balance, Accumulated impairment charge | 0 | 0
Ending balance, goodwill net | $ 288 | $ 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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