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Revenues - Transaction and Relationship Revenue (Detail) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 2,007 | $ 1,813 | $ 5,829 | $ 5,416
Percentage of revenues | 100.00% | 100.00% | 100.00% | 100.00%
Transaction Revenue |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 787 | $ 705 | $ 2,255 | $ 2,159
Percentage of revenues | 39.00% | 39.00% | 39.00% | 40.00%
Recurring Revenue |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 1,220 | $ 1,108 | $ 3,574 | $ 3,257
Percentage of revenues | 61.00% | 61.00% | 61.00% | 60.00%
MA |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 909 | $ 831 | $ 2,656 | $ 2,432
MA | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 912 | $ 834 | $ 2,665 | $ 2,442
Percentage of revenues | 100.00% | 100.00% | 100.00% | 100.00%
MA | DS Banking Product and Service | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 140 | $ 140 | $ 419 | $ 405
Percentage of revenues | 100.00% | 100.00% | 100.00% | 100.00%
MA | Insurance | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 171 | $ 148 | $ 502 | $ 439
Percentage of revenues | 100.00% | 100.00% | 100.00% | 100.00%
MA | KYC | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 113 | $ 95 | $ 321 | $ 270
Percentage of revenues | 100.00% | 100.00% | 100.00% | 100.00%
MA | Decision Solutions (DS) |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 424 | $ 383 |  |
MA | Decision Solutions (DS) | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 424 | $ 383 | $ 1,242 | $ 1,114
Percentage of revenues | 100.00% | 100.00% | 100.00% | 100.00%
MA | Research and Insights (R&I) |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 252 | $ 235 |  |
MA | Research and Insights (R&I) | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 252 | $ 235 | $ 737 | $ 683
Percentage of revenues | 100.00% | 100.00% | 100.00% | 100.00%
MA | Data and Information (D&I) |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 233 | $ 213 |  |
MA | Data and Information (D&I) | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 233 | $ 213 | $ 677 | $ 635
Percentage of revenues | 100.00% | 100.00% | 100.00% | 100.00%
MA | Transaction Revenue |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 34 | $ 42 | $ 107 | $ 127
MA | Transaction Revenue | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Percentage of revenues | 4.00% | 5.00% | 4.00% | 5.00%
MA | Transaction Revenue | DS Banking Product and Service | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 25 | $ 28 | $ 76 | $ 85
Percentage of revenues | 18.00% | 20.00% | 18.00% | 21.00%
MA | Transaction Revenue | Insurance | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 3 | $ 6 | $ 15 | $ 20
Percentage of revenues | 2.00% | 4.00% | 3.00% | 5.00%
MA | Transaction Revenue | KYC | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 1 | $ 3 | $ 1 | $ 6
Percentage of revenues | 1.00% | 3.00% | 0.00% | 2.00%
MA | Transaction Revenue | Decision Solutions (DS) | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 29 | $ 37 | $ 92 | $ 111
Percentage of revenues | 7.00% | 10.00% | 7.00% | 10.00%
MA | Transaction Revenue | Research and Insights (R&I) | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 3 | $ 3 | $ 9 | $ 9
Percentage of revenues | 1.00% | 1.00% | 1.00% | 1.00%
MA | Transaction Revenue | Data and Information (D&I) | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 2 | $ 2 | $ 6 | $ 7
Percentage of revenues | 1.00% | 1.00% | 1.00% | 1.00%
MA | Recurring Revenue |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 875 | $ 789 | $ 2,549 | $ 2,305
MA | Recurring Revenue | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Percentage of revenues | 96.00% | 95.00% | 96.00% | 95.00%
MA | Recurring Revenue | DS Banking Product and Service | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 115 | $ 112 | $ 343 | $ 320
Percentage of revenues | 82.00% | 80.00% | 82.00% | 79.00%
MA | Recurring Revenue | Insurance | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 168 | $ 142 | $ 487 | $ 419
Percentage of revenues | 98.00% | 96.00% | 97.00% | 95.00%
MA | Recurring Revenue | KYC | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 112 | $ 92 | $ 320 | $ 264
Percentage of revenues | 99.00% | 97.00% | 100.00% | 98.00%
MA | Recurring Revenue | Decision Solutions (DS) | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 395 | $ 346 | $ 1,150 | $ 1,003
Percentage of revenues | 93.00% | 90.00% | 93.00% | 90.00%
MA | Recurring Revenue | Research and Insights (R&I) | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 249 | $ 232 | $ 728 | $ 674
Percentage of revenues | 99.00% | 99.00% | 99.00% | 99.00%
MA | Recurring Revenue | Data and Information (D&I) | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 231 | $ 211 | $ 671 | $ 628
Percentage of revenues | 99.00% | 99.00% | 99.00% | 99.00%
MIS |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 1,098 | $ 982 | $ 3,173 | $ 2,984
MIS | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 1,148 | $ 1,030 | $ 3,322 | $ 3,128
Percentage of revenues | 100.00% | 100.00% | 100.00% | 100.00%
MIS | Corporate Finance (CFG) |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 576 | $ 515 |  |
MIS | Corporate Finance (CFG) | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 576 | $ 515 | $ 1,652 | $ 1,569
Percentage of revenues | 100.00% | 100.00% | 100.00% | 100.00%
MIS | Structured Finance (SFG) |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 146 | $ 135 |  |
MIS | Structured Finance (SFG) | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 146 | $ 135 | $ 419 | $ 380
Percentage of revenues | 100.00% | 100.00% | 100.00% | 100.00%
MIS | Financial Institutions (FIG) |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 208 | $ 170 |  |
MIS | Financial Institutions (FIG) | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 208 | $ 170 | $ 590 | $ 560
Percentage of revenues | 100.00% | 100.00% | 100.00% | 100.00%
MIS | Public, Project and Infrastructure Finance (PPIF) |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 161 | $ 154 |  |
MIS | Public, Project and Infrastructure Finance (PPIF) | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 161 | $ 154 | $ 486 | $ 449
Percentage of revenues | 100.00% | 100.00% | 100.00% | 100.00%
MIS | MIS Other |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 7 | $ 8 |  |
MIS | MIS Other | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 7 | $ 8 | $ 26 | $ 26
Percentage of revenues | 100.00% | 100.00% | 100.00% | 100.00%
MIS | Transaction Revenue |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 753 | $ 663 | $ 2,148 | $ 2,032
MIS | Transaction Revenue | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Percentage of revenues | 69.00% | 68.00% | 68.00% | 68.00%
MIS | Transaction Revenue | Corporate Finance (CFG) | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 433 | $ 382 | $ 1,225 | $ 1,169
Percentage of revenues | 75.00% | 74.00% | 74.00% | 75.00%
MIS | Transaction Revenue | Structured Finance (SFG) | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 86 | $ 78 | $ 238 | $ 213
Percentage of revenues | 59.00% | 58.00% | 57.00% | 56.00%
MIS | Transaction Revenue | Financial Institutions (FIG) | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 123 | $ 92 | $ 340 | $ 329
Percentage of revenues | 59.00% | 54.00% | 58.00% | 59.00%
MIS | Transaction Revenue | Public, Project and Infrastructure Finance (PPIF) | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 111 | $ 109 | $ 340 | $ 315
Percentage of revenues | 69.00% | 71.00% | 70.00% | 70.00%
MIS | Transaction Revenue | MIS Other | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 0 | $ 2 | $ 5 | $ 6
Percentage of revenues | 0.00% | 25.00% | 19.00% | 23.00%
MIS | Recurring Revenue |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 345 | $ 319 | $ 1,025 | $ 952
MIS | Recurring Revenue | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Percentage of revenues | 31.00% | 32.00% | 32.00% | 32.00%
MIS | Recurring Revenue | Corporate Finance (CFG) | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 143 | $ 133 | $ 427 | $ 400
Percentage of revenues | 25.00% | 26.00% | 26.00% | 25.00%
MIS | Recurring Revenue | Structured Finance (SFG) | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 60 | $ 57 | $ 181 | $ 167
Percentage of revenues | 41.00% | 42.00% | 43.00% | 44.00%
MIS | Recurring Revenue | Financial Institutions (FIG) | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 85 | $ 78 | $ 250 | $ 231
Percentage of revenues | 41.00% | 46.00% | 42.00% | 41.00%
MIS | Recurring Revenue | Public, Project and Infrastructure Finance (PPIF) | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 50 | $ 45 | $ 146 | $ 134
Percentage of revenues | 31.00% | 29.00% | 30.00% | 30.00%
MIS | Recurring Revenue | MIS Other | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 7 | $ 6 | $ 21 | $ 20
Percentage of revenues | 100.00% | 75.00% | 81.00% | 77.00%

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